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    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_QuotaShareReinsuranceAgreement2020TwoYearMember" xlink:to="lab_mtg_QuotaShareReinsuranceAgreement2020TwoYearMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_19205bbe-a1c8-467a-a890-8d700c2e5a6e_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Vested (in shares)</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent_febe9850-1640-44a3-bc0d-fc26da222259_verboseLabel_en-US" xlink:label="lab_us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Employee contributions subject to employer match (in hundredths)</link:label>
    <link:label id="lab_us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent_label_en-US" xlink:label="lab_us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent" xlink:to="lab_us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_SecurityExchangeName_73be4826-f6fd-4a01-90e2-f4c55a69f925_terseLabel_en-US" xlink:label="lab_dei_SecurityExchangeName" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Security Exchange Name</link:label>
    <link:label id="lab_dei_SecurityExchangeName_label_en-US" xlink:label="lab_dei_SecurityExchangeName" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Security Exchange Name</link:label>
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    <link:label id="lab_us-gaap_DefinedBenefitPlanPlanAmendments_91c7f4a0-85af-404f-a53b-53eda7974712_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanPlanAmendments" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Plan Amendments</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanPlanAmendments_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanPlanAmendments" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Defined Benefit Plan, Benefit Obligation, Increase (Decrease) for Plan Amendment</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanPlanAmendments" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DefinedBenefitPlanPlanAmendments"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanPlanAmendments" xlink:to="lab_us-gaap_DefinedBenefitPlanPlanAmendments" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CommoditiesInvestmentMember_2a2b4e87-6fed-46b5-9eda-68efcc1ce186_terseLabel_en-US" xlink:label="lab_us-gaap_CommoditiesInvestmentMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Commodities</link:label>
    <link:label id="lab_us-gaap_CommoditiesInvestmentMember_label_en-US" xlink:label="lab_us-gaap_CommoditiesInvestmentMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Commodities Investment [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommoditiesInvestmentMember" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CommoditiesInvestmentMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommoditiesInvestmentMember" xlink:to="lab_us-gaap_CommoditiesInvestmentMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_Revenues_b2c0cca5-f4e4-4dc8-82a6-4595fb51c6b0_totalLabel_en-US" xlink:label="lab_us-gaap_Revenues" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Total revenues</link:label>
    <link:label id="lab_us-gaap_Revenues_label_en-US" xlink:label="lab_us-gaap_Revenues" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Revenues</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Revenues" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_Revenues"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_Revenues" xlink:to="lab_us-gaap_Revenues" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_PrimaryDefaultInventory_6d49dbd7-7e87-4042-a7a6-b421f99b07ef_periodStartLabel_en-US" xlink:label="lab_mtg_PrimaryDefaultInventory" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Beginning delinquent inventory</link:label>
    <link:label id="lab_mtg_PrimaryDefaultInventory_730e3a99-8655-48d6-b1c5-b3b612ff059d_periodEndLabel_en-US" xlink:label="lab_mtg_PrimaryDefaultInventory" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Ending delinquent inventory</link:label>
    <link:label id="lab_mtg_PrimaryDefaultInventory_8ca0c336-0fdc-4dd7-a1cd-d15d748933ce_totalLabel_en-US" xlink:label="lab_mtg_PrimaryDefaultInventory" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Total primary default inventory</link:label>
    <link:label id="lab_mtg_PrimaryDefaultInventory_label_en-US" xlink:label="lab_mtg_PrimaryDefaultInventory" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Primary Default Inventory</link:label>
    <link:label id="lab_mtg_PrimaryDefaultInventory_documentation_en-US" xlink:label="lab_mtg_PrimaryDefaultInventory" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">The number of loans in the primary default inventory.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_PrimaryDefaultInventory" xlink:href="mtg-20201231.xsd#mtg_PrimaryDefaultInventory"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_PrimaryDefaultInventory" xlink:to="lab_mtg_PrimaryDefaultInventory" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_PrimaryDefaultInventoryTwelveMonthsOrMore_7f422402-d42f-42d7-a35f-1f8208879952_verboseLabel_en-US" xlink:label="lab_mtg_PrimaryDefaultInventoryTwelveMonthsOrMore" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">12 months or more</link:label>
    <link:label id="lab_mtg_PrimaryDefaultInventoryTwelveMonthsOrMore_label_en-US" xlink:label="lab_mtg_PrimaryDefaultInventoryTwelveMonthsOrMore" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Primary Default Inventory, Twelve Months or More</link:label>
    <link:label id="lab_mtg_PrimaryDefaultInventoryTwelveMonthsOrMore_documentation_en-US" xlink:label="lab_mtg_PrimaryDefaultInventoryTwelveMonthsOrMore" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">The number of loans that have been in the primary default inventory for twelve months or more as of the balance sheet date.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_PrimaryDefaultInventoryTwelveMonthsOrMore" xlink:href="mtg-20201231.xsd#mtg_PrimaryDefaultInventoryTwelveMonthsOrMore"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_PrimaryDefaultInventoryTwelveMonthsOrMore" xlink:to="lab_mtg_PrimaryDefaultInventoryTwelveMonthsOrMore" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CarryingReportedAmountFairValueDisclosureMember_fa028725-3c39-4d83-a1d7-694bdf0e4c79_terseLabel_en-US" xlink:label="lab_us-gaap_CarryingReportedAmountFairValueDisclosureMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Carrying Value</link:label>
    <link:label id="lab_us-gaap_CarryingReportedAmountFairValueDisclosureMember_label_en-US" xlink:label="lab_us-gaap_CarryingReportedAmountFairValueDisclosureMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Reported Value Measurement [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CarryingReportedAmountFairValueDisclosureMember" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CarryingReportedAmountFairValueDisclosureMember"/>
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    <link:label id="lab_mtg_CededPremiumsWrittenandEarnedNetofProfitCommission_8cac93d1-eefe-42a7-af75-86d1d90823f8_terseLabel_en-US" xlink:label="lab_mtg_CededPremiumsWrittenandEarnedNetofProfitCommission" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Ceded premiums written and earned, net of profit commission</link:label>
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    <link:loc xlink:type="locator" xlink:label="loc_mtg_CededPremiumsWrittenandEarnedNetofProfitCommission" xlink:href="mtg-20201231.xsd#mtg_CededPremiumsWrittenandEarnedNetofProfitCommission"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_CededPremiumsWrittenandEarnedNetofProfitCommission" xlink:to="lab_mtg_CededPremiumsWrittenandEarnedNetofProfitCommission" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfQuarterlyFinancialInformationTableTextBlock_1945f9e0-fd1a-4ade-ad95-621f82e06d75_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfQuarterlyFinancialInformationTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Unaudited quarterly financial data</link:label>
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    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfQuarterlyFinancialInformationTableTextBlock" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfQuarterlyFinancialInformationTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfQuarterlyFinancialInformationTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfQuarterlyFinancialInformationTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_DefinedBenefitPlanMinimumValueOfOutstandingNoncallableBondsUsedInHypotheticalCashFlowBondMatchingExercise_9b79c89c-cf52-4aa2-8466-066aeb44ce3f_verboseLabel_en-US" xlink:label="lab_mtg_DefinedBenefitPlanMinimumValueOfOutstandingNoncallableBondsUsedInHypotheticalCashFlowBondMatchingExercise" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Minimum value of outstanding noncallable bonds used in hypothetical cash flow bond matching exercise</link:label>
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    <link:label id="lab_mtg_DefinedBenefitPlanMinimumValueOfOutstandingNoncallableBondsUsedInHypotheticalCashFlowBondMatchingExercise_documentation_en-US" xlink:label="lab_mtg_DefinedBenefitPlanMinimumValueOfOutstandingNoncallableBondsUsedInHypotheticalCashFlowBondMatchingExercise" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">The minimum value of outstanding noncallable bonds used in a hypothetical cash flow bond matching exercise for purposes of selecting a discount rate related to actuarial assumptions used in the valuation of projected benefit obligations, net periodic benefit costs and accumulated postretirement benefit obligation.</link:label>
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    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentNet_47846c9c-0625-4376-84df-e11d56b9600f_terseLabel_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentNet" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Home office and equipment, net</link:label>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentNet_label_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentNet" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Property, Plant and Equipment, Net</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentNet" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PropertyPlantAndEquipmentNet"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentNet" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentNet" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_StatutoryCapitalRequirementsRiskToCapitalRatioForCombinedInsuranceOperations_2a1756e2-b128-4fbf-a8d9-6d5b3b637e35_terseLabel_en-US" xlink:label="lab_mtg_StatutoryCapitalRequirementsRiskToCapitalRatioForCombinedInsuranceOperations" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Risk-to-capital ratio on combined insurance operations</link:label>
    <link:label id="lab_mtg_StatutoryCapitalRequirementsRiskToCapitalRatioForCombinedInsuranceOperations_label_en-US" xlink:label="lab_mtg_StatutoryCapitalRequirementsRiskToCapitalRatioForCombinedInsuranceOperations" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Statutory Capital Requirements, Risk To Capital Ratio For Combined Insurance Operations</link:label>
    <link:label id="lab_mtg_StatutoryCapitalRequirementsRiskToCapitalRatioForCombinedInsuranceOperations_documentation_en-US" xlink:label="lab_mtg_StatutoryCapitalRequirementsRiskToCapitalRatioForCombinedInsuranceOperations" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Statutory Capital Requirements, Risk To Capital Ratio For Combined Insurance Operations</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_StatutoryCapitalRequirementsRiskToCapitalRatioForCombinedInsuranceOperations" xlink:href="mtg-20201231.xsd#mtg_StatutoryCapitalRequirementsRiskToCapitalRatioForCombinedInsuranceOperations"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_StatutoryCapitalRequirementsRiskToCapitalRatioForCombinedInsuranceOperations" xlink:to="lab_mtg_StatutoryCapitalRequirementsRiskToCapitalRatioForCombinedInsuranceOperations" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_DirectDomesticPrimaryInsuranceInForce_1130b196-2ade-4497-87b1-de1da4c6d762_verboseLabel_en-US" xlink:label="lab_mtg_DirectDomesticPrimaryInsuranceInForce" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Direct domestic primary insurance in force</link:label>
    <link:label id="lab_mtg_DirectDomesticPrimaryInsuranceInForce_label_en-US" xlink:label="lab_mtg_DirectDomesticPrimaryInsuranceInForce" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Direct Domestic Primary Insurance In Force</link:label>
    <link:label id="lab_mtg_DirectDomesticPrimaryInsuranceInForce_documentation_en-US" xlink:label="lab_mtg_DirectDomesticPrimaryInsuranceInForce" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">The principal balance in a Company's records of all mortgage loans it insures.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_DirectDomesticPrimaryInsuranceInForce" xlink:href="mtg-20201231.xsd#mtg_DirectDomesticPrimaryInsuranceInForce"/>
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    <link:label id="lab_us-gaap_AccumulatedOtherComprehensiveIncomeMember_c447d44c-5930-40a2-8ce4-5583d71e6396_terseLabel_en-US" xlink:label="lab_us-gaap_AccumulatedOtherComprehensiveIncomeMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Accumulated other comprehensive income (loss)</link:label>
    <link:label id="lab_us-gaap_AccumulatedOtherComprehensiveIncomeMember_label_en-US" xlink:label="lab_us-gaap_AccumulatedOtherComprehensiveIncomeMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">AOCI Attributable to Parent [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember" xlink:to="lab_us-gaap_AccumulatedOtherComprehensiveIncomeMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_0d7bfd8a-f28d-43bf-8613-d5ebe1bffa54_terseLabel_en-US" xlink:label="lab_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Basis spread on variable rate</link:label>
    <link:label id="lab_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_label_en-US" xlink:label="lab_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Debt Instrument, Basis Spread on Variable Rate</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentBasisSpreadOnVariableRate1"/>
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    <link:label id="lab_us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentBeforeTaxPortionAttributableToParent_92a3a14e-f8e9-47c1-ad34-c4acba9461de_terseLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentBeforeTaxPortionAttributableToParent" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Net unrealized investment gains (losses) on securities without an allowance for credit losses</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentBeforeTaxPortionAttributableToParent_label_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentBeforeTaxPortionAttributableToParent" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Tax, Portion Attributable to Parent</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentBeforeTaxPortionAttributableToParent" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentBeforeTaxPortionAttributableToParent"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentBeforeTaxPortionAttributableToParent" xlink:to="lab_us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentBeforeTaxPortionAttributableToParent" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTextBlock_3bc3a62f-f759-40f2-af7e-c6864fd0d755_terseLabel_en-US" xlink:label="lab_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Reconciliation of beginning and ending balance for assets and liabilities measured at fair value with significant unobservable inputs (level 3)</link:label>
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    <link:label id="lab_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_29b23efc-0f78-4fd1-afab-0c9089218e6a_negatedLabel_en-US" xlink:label="lab_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Gross Unrealized Losses</link:label>
    <link:label id="lab_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_label_en-US" xlink:label="lab_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax" xlink:to="lab_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_IncreaseDecreaseInBrokerDealerRelatedReceivablesPayablesNet_7f0fd538-e53c-4f32-a1f9-9a9a762af4d9_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInBrokerDealerRelatedReceivablesPayablesNet" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Net decrease in payables for securities</link:label>
    <link:label id="lab_us-gaap_IncreaseDecreaseInBrokerDealerRelatedReceivablesPayablesNet_label_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInBrokerDealerRelatedReceivablesPayablesNet" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Increase (Decrease) in Broker-Dealer Related Receivables (Payables), Net</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInBrokerDealerRelatedReceivablesPayablesNet" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncreaseDecreaseInBrokerDealerRelatedReceivablesPayablesNet"/>
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    <link:label id="lab_us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense_126a1733-c622-4310-b678-eed40cedc196_verboseLabel_en-US" xlink:label="lab_us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Prior years</link:label>
    <link:label id="lab_us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense_08f7c914-5ef6-414a-ad65-36097f732e95_terseLabel_en-US" xlink:label="lab_us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Prior years</link:label>
    <link:label id="lab_us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense_label_en-US" xlink:label="lab_us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Prior Year Claims and Claims Adjustment Expense</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense"/>
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    <link:label id="lab_us-gaap_RepaymentsOfLongTermDebt_e2d07d46-e0f9-4248-baf4-5a53ed616291_terseLabel_en-US" xlink:label="lab_us-gaap_RepaymentsOfLongTermDebt" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Repayments of long-term debt</link:label>
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    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RepaymentsOfLongTermDebt" xlink:to="lab_us-gaap_RepaymentsOfLongTermDebt" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfInvestmentIncomeReportedAmountsByCategoryLineItems_e5cdea73-ac56-4542-98a7-2a61d0d85607_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfInvestmentIncomeReportedAmountsByCategoryLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Schedule of Investment Income, Reported Amounts, by Category [Line Items]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfInvestmentIncomeReportedAmountsByCategoryLineItems_label_en-US" xlink:label="lab_us-gaap_ScheduleOfInvestmentIncomeReportedAmountsByCategoryLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Net Investment Income [Line Items]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentIncomeReportedAmountsByCategoryLineItems" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfInvestmentIncomeReportedAmountsByCategoryLineItems"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfInvestmentIncomeReportedAmountsByCategoryLineItems" xlink:to="lab_us-gaap_ScheduleOfInvestmentIncomeReportedAmountsByCategoryLineItems" xlink:type="arc" order="1"/>
    <link:label id="lab_srt_ScenarioUnspecifiedDomain_08263f49-3584-4427-a2f7-77a0ead636b1_terseLabel_en-US" xlink:label="lab_srt_ScenarioUnspecifiedDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Scenario [Domain]</link:label>
    <link:label id="lab_srt_ScenarioUnspecifiedDomain_label_en-US" xlink:label="lab_srt_ScenarioUnspecifiedDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Scenario [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScenarioUnspecifiedDomain" xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ScenarioUnspecifiedDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_ScenarioUnspecifiedDomain" xlink:to="lab_srt_ScenarioUnspecifiedDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_MaximumPercentageOfAggregatePrincipalAmountOfDebentures_962f9319-df42-402f-9b8e-a5d7c91bb1b5_verboseLabel_en-US" xlink:label="lab_mtg_MaximumPercentageOfAggregatePrincipalAmountOfDebentures" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Maximum percentage of aggregate principal amount of the debentures (in hundredths)</link:label>
    <link:label id="lab_mtg_MaximumPercentageOfAggregatePrincipalAmountOfDebentures_label_en-US" xlink:label="lab_mtg_MaximumPercentageOfAggregatePrincipalAmountOfDebentures" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Maximum percentage of aggregate principal amount of the debentures</link:label>
    <link:label id="lab_mtg_MaximumPercentageOfAggregatePrincipalAmountOfDebentures_documentation_en-US" xlink:label="lab_mtg_MaximumPercentageOfAggregatePrincipalAmountOfDebentures" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">The maximum ratio of total net proceeds of all issuances of qualifying securities to the aggregate principal amount of the debentures. Pursuant to the Alternative Payment Mechanism under the note agreement(s), the entity may not issue qualifying preferred stock if the total net proceeds exceed this ratio.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_MaximumPercentageOfAggregatePrincipalAmountOfDebentures" xlink:href="mtg-20201231.xsd#mtg_MaximumPercentageOfAggregatePrincipalAmountOfDebentures"/>
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    <link:label id="lab_us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract_d9bf53e4-8f3d-4f44-bc9e-5f256e490819_terseLabel_en-US" xlink:label="lab_us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Share-based Payment Arrangement [Abstract]</link:label>
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    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract"/>
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    <link:label id="lab_us-gaap_RelatedPartyTransactionAmountsOfTransaction_319d8b36-0cf5-4cc4-9ad0-42d95ca4e1b5_terseLabel_en-US" xlink:label="lab_us-gaap_RelatedPartyTransactionAmountsOfTransaction" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Related party transaction amount</link:label>
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    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RelatedPartyTransactionAmountsOfTransaction" xlink:to="lab_us-gaap_RelatedPartyTransactionAmountsOfTransaction" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_PercentOfDelinquentReinsuredLoanstoTotalReinsuredLoans_65286842-b985-4432-9eaa-f10d9af92516_terseLabel_en-US" xlink:label="lab_mtg_PercentOfDelinquentReinsuredLoanstoTotalReinsuredLoans" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Percent of delinquent reinsured loans to total reinsured loans</link:label>
    <link:label id="lab_mtg_PercentOfDelinquentReinsuredLoanstoTotalReinsuredLoans_label_en-US" xlink:label="lab_mtg_PercentOfDelinquentReinsuredLoanstoTotalReinsuredLoans" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Percent Of Delinquent Reinsured Loans to Total Reinsured Loans</link:label>
    <link:label id="lab_mtg_PercentOfDelinquentReinsuredLoanstoTotalReinsuredLoans_documentation_en-US" xlink:label="lab_mtg_PercentOfDelinquentReinsuredLoanstoTotalReinsuredLoans" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">The percent of delinquent reinsured principal balance of loans to total reinsured principal balance of loans that causes a trigger event if exceeded.</link:label>
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    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_PercentOfDelinquentReinsuredLoanstoTotalReinsuredLoans" xlink:to="lab_mtg_PercentOfDelinquentReinsuredLoanstoTotalReinsuredLoans" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_IncreaseDecreaseInOtherInsuranceLiabilities_b08af367-1f01-4d15-95a2-8a3691d5d98c_verboseLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInOtherInsuranceLiabilities" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Return premium accrual</link:label>
    <link:label id="lab_us-gaap_IncreaseDecreaseInOtherInsuranceLiabilities_label_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInOtherInsuranceLiabilities" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Increase (Decrease) in Other Insurance Liabilities</link:label>
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    <link:label id="lab_mtg_StatutoryCapitalAbstract_b9f3c219-2dc3-43c5-9117-6da7b9dc869e_terseLabel_en-US" xlink:label="lab_mtg_StatutoryCapitalAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Statutory Capital [Abstract]</link:label>
    <link:label id="lab_mtg_StatutoryCapitalAbstract_label_en-US" xlink:label="lab_mtg_StatutoryCapitalAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Statutory Capital [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_StatutoryCapitalAbstract" xlink:href="mtg-20201231.xsd#mtg_StatutoryCapitalAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_StatutoryCapitalAbstract" xlink:to="lab_mtg_StatutoryCapitalAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable_2169729c-c17b-4538-9c15-3035d519685f_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Schedule of Defined Benefit Plans Disclosures [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable_label_en-US" xlink:label="lab_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Schedule of Defined Benefit Plans Disclosures [Table]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable" xlink:to="lab_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_15e62b9c-d702-4038-8e30-2a30cf3c0a89_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_label_en-US" xlink:label="lab_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
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    <link:label id="lab_us-gaap_EarningsPerShareDilutedAbstract_2d17dc00-a6f0-407a-87e5-f29d21e7cd47_terseLabel_en-US" xlink:label="lab_us-gaap_EarningsPerShareDilutedAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Diluted earnings per share [Abstract]</link:label>
    <link:label id="lab_us-gaap_EarningsPerShareDilutedAbstract_label_en-US" xlink:label="lab_us-gaap_EarningsPerShareDilutedAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Earnings Per Share, Diluted [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareDilutedAbstract" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EarningsPerShareDilutedAbstract"/>
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    <link:label id="lab_mtg_PoolInsuranceNoticeInventory_b6d125f0-e8d1-41cf-a2e6-f3b0d52660fc_verboseLabel_en-US" xlink:label="lab_mtg_PoolInsuranceNoticeInventory" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Pool insurance notice inventory (in number of loans)</link:label>
    <link:label id="lab_mtg_PoolInsuranceNoticeInventory_label_en-US" xlink:label="lab_mtg_PoolInsuranceNoticeInventory" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Pool insurance notice inventory</link:label>
    <link:label id="lab_mtg_PoolInsuranceNoticeInventory_documentation_en-US" xlink:label="lab_mtg_PoolInsuranceNoticeInventory" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">The number of loans included in the pool insurance notice inventory as of the end of the reporting period.</link:label>
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    <link:label id="lab_dei_EntitySmallBusiness_40495574-8634-4b34-bbb4-48971980a53a_terseLabel_en-US" xlink:label="lab_dei_EntitySmallBusiness" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Entity Small Business</link:label>
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    <link:label id="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour_ea6b00fa-adae-47f2-a1ca-cf8abfae387f_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Expected Benefit Payments for the Year Ending: Current plus 4</link:label>
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    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour"/>
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    <link:label id="lab_mtg_TotalRealizedUnrealizedGainsLossesAbstract_4123457e-3c4f-403f-b804-ec0c01be706d_verboseLabel_en-US" xlink:label="lab_mtg_TotalRealizedUnrealizedGainsLossesAbstract" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Total realized/unrealized gains (losses) [Abstract]</link:label>
    <link:label id="lab_mtg_TotalRealizedUnrealizedGainsLossesAbstract_label_en-US" xlink:label="lab_mtg_TotalRealizedUnrealizedGainsLossesAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Total realized/unrealized gains (losses) [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_TotalRealizedUnrealizedGainsLossesAbstract" xlink:href="mtg-20201231.xsd#mtg_TotalRealizedUnrealizedGainsLossesAbstract"/>
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    <link:label id="lab_mtg_A2020PlanMember_4eb57093-4f7b-432b-a878-0c55f281a6b0_terseLabel_en-US" xlink:label="lab_mtg_A2020PlanMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">2020 Plan</link:label>
    <link:label id="lab_mtg_A2020PlanMember_label_en-US" xlink:label="lab_mtg_A2020PlanMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">2020 Plan [Member]</link:label>
    <link:label id="lab_mtg_A2020PlanMember_documentation_en-US" xlink:label="lab_mtg_A2020PlanMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">2020 Plan</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_A2020PlanMember" xlink:href="mtg-20201231.xsd#mtg_A2020PlanMember"/>
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    <link:label id="lab_mtg_DebtInstrumentConvertibleConversionPrice2_4ef2feb0-aec1-44c9-ae7e-abde336356e8_verboseLabel_en-US" xlink:label="lab_mtg_DebtInstrumentConvertibleConversionPrice2" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Closing sale price of our common stock for consideration of redemption (in dollars per share)</link:label>
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    <link:label id="lab_mtg_DebtInstrumentConvertibleConversionPrice2_documentation_en-US" xlink:label="lab_mtg_DebtInstrumentConvertibleConversionPrice2" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">The price per share of the conversion feature embedded in the debt instrument.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_DebtInstrumentConvertibleConversionPrice2" xlink:href="mtg-20201231.xsd#mtg_DebtInstrumentConvertibleConversionPrice2"/>
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    <link:label id="lab_us-gaap_EarningsPerShareBasic_7fa33c5f-8fcd-4441-84fd-3ed4a275da78_verboseLabel_en-US" xlink:label="lab_us-gaap_EarningsPerShareBasic" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Basic (in dollars per share)</link:label>
    <link:label id="lab_us-gaap_EarningsPerShareBasic_b4ac35b5-05d9-4bcb-a572-f3608a42587a_terseLabel_en-US" xlink:label="lab_us-gaap_EarningsPerShareBasic" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Basic earnings per share (in dollars per share)</link:label>
    <link:label id="lab_us-gaap_EarningsPerShareBasic_label_en-US" xlink:label="lab_us-gaap_EarningsPerShareBasic" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Earnings Per Share, Basic</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareBasic" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EarningsPerShareBasic"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EarningsPerShareBasic" xlink:to="lab_us-gaap_EarningsPerShareBasic" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesFairValue_feef62df-6d5f-44a4-b370-4fa8df551cb2_terseLabel_en-US" xlink:label="lab_us-gaap_SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesFairValue" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Fair Value</link:label>
    <link:label id="lab_us-gaap_SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesFairValue_label_en-US" xlink:label="lab_us-gaap_SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesFairValue" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties, Fair Value</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesFairValue" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesFairValue"/>
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    <link:label id="lab_dei_AmendmentFlag_94959396-0723-42b8-8aa7-1c53e5db315c_terseLabel_en-US" xlink:label="lab_dei_AmendmentFlag" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Amendment Flag</link:label>
    <link:label id="lab_dei_AmendmentFlag_label_en-US" xlink:label="lab_dei_AmendmentFlag" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Amendment Flag</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_AmendmentFlag" xlink:href="https://xbrl.sec.gov/dei/2020/dei-2020-01-31.xsd#dei_AmendmentFlag"/>
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    <link:label id="lab_us-gaap_ComprehensiveIncomeNetOfTax_d39a8a7b-440b-4ea1-b47b-6c3e166b86f7_totalLabel_en-US" xlink:label="lab_us-gaap_ComprehensiveIncomeNetOfTax" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Comprehensive income</link:label>
    <link:label id="lab_us-gaap_ComprehensiveIncomeNetOfTax_label_en-US" xlink:label="lab_us-gaap_ComprehensiveIncomeNetOfTax" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Comprehensive Income (Loss), Net of Tax, Attributable to Parent</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComprehensiveIncomeNetOfTax" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ComprehensiveIncomeNetOfTax"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTax" xlink:to="lab_us-gaap_ComprehensiveIncomeNetOfTax" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_SubsequentEventTypeAxis_34a1e251-71c6-43cc-8d01-58b9ff8bdbf5_terseLabel_en-US" xlink:label="lab_us-gaap_SubsequentEventTypeAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Subsequent Event Type [Axis]</link:label>
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    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeAxis" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SubsequentEventTypeAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SubsequentEventTypeAxis" xlink:to="lab_us-gaap_SubsequentEventTypeAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_b767eedc-1638-4658-b410-2eec8621c188_terseLabel_en-US" xlink:label="lab_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]</link:label>
    <link:label id="lab_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_label_en-US" xlink:label="lab_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward" xlink:to="lab_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths_aa5b2824-ceb6-466f-acb5-ba11744569f9_terseLabel_en-US" xlink:label="lab_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">2021</link:label>
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    <link:label id="lab_us-gaap_EffectiveIncomeTaxRateReconciliationOtherAdjustments_label_en-US" xlink:label="lab_us-gaap_EffectiveIncomeTaxRateReconciliationOtherAdjustments" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Effective Income Tax Rate Reconciliation, Other Adjustments, Percent</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationOtherAdjustments" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationOtherAdjustments"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateReconciliationOtherAdjustments" xlink:to="lab_us-gaap_EffectiveIncomeTaxRateReconciliationOtherAdjustments" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_ExcessofLossReinsuranceAgreementsHomeReEntitiesMember_0b5beb8d-125a-462a-8deb-0a8096c76986_terseLabel_en-US" xlink:label="lab_mtg_ExcessofLossReinsuranceAgreementsHomeReEntitiesMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Excess of Loss Reinsurance Agreements, Home Re Entities</link:label>
    <link:label id="lab_mtg_ExcessofLossReinsuranceAgreementsHomeReEntitiesMember_label_en-US" xlink:label="lab_mtg_ExcessofLossReinsuranceAgreementsHomeReEntitiesMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Excess of Loss Reinsurance Agreements, Home Re Entities [Member]</link:label>
    <link:label id="lab_mtg_ExcessofLossReinsuranceAgreementsHomeReEntitiesMember_documentation_en-US" xlink:label="lab_mtg_ExcessofLossReinsuranceAgreementsHomeReEntitiesMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Excess of Loss Reinsurance Agreements, Home Re Entities [Member]</link:label>
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    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_ExcessofLossReinsuranceAgreementsHomeReEntitiesMember" xlink:to="lab_mtg_ExcessofLossReinsuranceAgreementsHomeReEntitiesMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlementsAndCurtailments1_fdafd330-61c6-46d9-a5c0-9ac7b7180fda_negatedLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlementsAndCurtailments1" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Cost of settlements</link:label>
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    <link:label id="lab_us-gaap_DepreciationAmortizationAndAccretionNet_6f8c68c3-0f4a-47b4-859e-3d87ee0bc84a_terseLabel_en-US" xlink:label="lab_us-gaap_DepreciationAmortizationAndAccretionNet" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Depreciation and other amortization</link:label>
    <link:label id="lab_us-gaap_DepreciationAmortizationAndAccretionNet_label_en-US" xlink:label="lab_us-gaap_DepreciationAmortizationAndAccretionNet" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Depreciation, Amortization and Accretion, Net</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepreciationAmortizationAndAccretionNet" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DepreciationAmortizationAndAccretionNet"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DepreciationAmortizationAndAccretionNet" xlink:to="lab_us-gaap_DepreciationAmortizationAndAccretionNet" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_OperatingLeaseExpense_60c92ead-5dd5-4f8f-a67e-cca17643be19_terseLabel_en-US" xlink:label="lab_us-gaap_OperatingLeaseExpense" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Operating lease, expense</link:label>
    <link:label id="lab_us-gaap_OperatingLeaseExpense_label_en-US" xlink:label="lab_us-gaap_OperatingLeaseExpense" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Operating Lease, Expense</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseExpense" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OperatingLeaseExpense"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OperatingLeaseExpense" xlink:to="lab_us-gaap_OperatingLeaseExpense" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_PrimaryDefaultInventoryFourToElevenMonthsPercentage_67dd016e-a7a8-4397-a3da-e2b5d3f6199e_verboseLabel_en-US" xlink:label="lab_mtg_PrimaryDefaultInventoryFourToElevenMonthsPercentage" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">4 - 11 months (in hundredths)</link:label>
    <link:label id="lab_mtg_PrimaryDefaultInventoryFourToElevenMonthsPercentage_label_en-US" xlink:label="lab_mtg_PrimaryDefaultInventoryFourToElevenMonthsPercentage" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Primary Default Inventory, four to eleven months, Percentage</link:label>
    <link:label id="lab_mtg_PrimaryDefaultInventoryFourToElevenMonthsPercentage_documentation_en-US" xlink:label="lab_mtg_PrimaryDefaultInventoryFourToElevenMonthsPercentage" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">The percentage of loans that have been in the primary default inventory for at least four months but no greater than eleven months as of the balance sheet date.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_PrimaryDefaultInventoryFourToElevenMonthsPercentage" xlink:href="mtg-20201231.xsd#mtg_PrimaryDefaultInventoryFourToElevenMonthsPercentage"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_PrimaryDefaultInventoryFourToElevenMonthsPercentage" xlink:to="lab_mtg_PrimaryDefaultInventoryFourToElevenMonthsPercentage" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_OtherAssets_c5aae434-54b0-4a0d-9585-bfe74dd20a81_terseLabel_en-US" xlink:label="lab_us-gaap_OtherAssets" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Other assets</link:label>
    <link:label id="lab_us-gaap_OtherAssets_label_en-US" xlink:label="lab_us-gaap_OtherAssets" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Other Assets</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherAssets" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherAssets"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherAssets" xlink:to="lab_us-gaap_OtherAssets" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_PrimaryDefaultInventoryFourToElevenMonths_6bcd2bec-79db-45ac-84a9-881c1397f3cb_verboseLabel_en-US" xlink:label="lab_mtg_PrimaryDefaultInventoryFourToElevenMonths" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">4 - 11 months</link:label>
    <link:label id="lab_mtg_PrimaryDefaultInventoryFourToElevenMonths_label_en-US" xlink:label="lab_mtg_PrimaryDefaultInventoryFourToElevenMonths" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Primary Default Inventory, four to eleven months</link:label>
    <link:label id="lab_mtg_PrimaryDefaultInventoryFourToElevenMonths_documentation_en-US" xlink:label="lab_mtg_PrimaryDefaultInventoryFourToElevenMonths" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">The number of loans that have been in the primary default inventory for at least four months but no greater than eleven months as of the balance sheet date.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_PrimaryDefaultInventoryFourToElevenMonths" xlink:href="mtg-20201231.xsd#mtg_PrimaryDefaultInventoryFourToElevenMonths"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_PrimaryDefaultInventoryFourToElevenMonths" xlink:to="lab_mtg_PrimaryDefaultInventoryFourToElevenMonths" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ComprehensiveIncomeNetOfTaxAbstract_f1f8cbd9-b904-4c5e-9ca4-189f3b62f2b9_terseLabel_en-US" xlink:label="lab_us-gaap_ComprehensiveIncomeNetOfTaxAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]</link:label>
    <link:label id="lab_us-gaap_ComprehensiveIncomeNetOfTaxAbstract_label_en-US" xlink:label="lab_us-gaap_ComprehensiveIncomeNetOfTaxAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComprehensiveIncomeNetOfTaxAbstract" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ComprehensiveIncomeNetOfTaxAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTaxAbstract" xlink:to="lab_us-gaap_ComprehensiveIncomeNetOfTaxAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_InvestmentInSubsidiariesAtEquityInNetAssets_e22e7400-b6fa-4d12-b848-30c786bd885f_terseLabel_en-US" xlink:label="lab_mtg_InvestmentInSubsidiariesAtEquityInNetAssets" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Investment in subsidiaries, at equity in net assets</link:label>
    <link:label id="lab_mtg_InvestmentInSubsidiariesAtEquityInNetAssets_label_en-US" xlink:label="lab_mtg_InvestmentInSubsidiariesAtEquityInNetAssets" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Investment in subsidiaries, at equity in net assets</link:label>
    <link:label id="lab_mtg_InvestmentInSubsidiariesAtEquityInNetAssets_documentation_en-US" xlink:label="lab_mtg_InvestmentInSubsidiariesAtEquityInNetAssets" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">The amount of the entity's total investments in subsidiaries (the equity in net assets of consolidated subsidiaries).</link:label>
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    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_InvestmentInSubsidiariesAtEquityInNetAssets" xlink:to="lab_mtg_InvestmentInSubsidiariesAtEquityInNetAssets" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPlanBenefitObligationContributionsByPlanParticipant_1ce63e5f-bd09-4da8-bd53-f91ce160e6ac_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanBenefitObligationContributionsByPlanParticipant" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Plan Participants' Contributions</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanBenefitObligationContributionsByPlanParticipant_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanBenefitObligationContributionsByPlanParticipant" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Defined Benefit Plan, Benefit Obligation, Contributions by Plan Participant</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanBenefitObligationContributionsByPlanParticipant" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DefinedBenefitPlanBenefitObligationContributionsByPlanParticipant"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanBenefitObligationContributionsByPlanParticipant" xlink:to="lab_us-gaap_DefinedBenefitPlanBenefitObligationContributionsByPlanParticipant" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_DeferredTaxAssetsLiabilitiesNetOther_931159d8-48a5-4a56-be3e-9c2219fdc31e_terseLabel_en-US" xlink:label="lab_mtg_DeferredTaxAssetsLiabilitiesNetOther" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Other, net</link:label>
    <link:label id="lab_mtg_DeferredTaxAssetsLiabilitiesNetOther_label_en-US" xlink:label="lab_mtg_DeferredTaxAssetsLiabilitiesNetOther" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Deferred Tax Assets (Liabilities), Net, Other</link:label>
    <link:label id="lab_mtg_DeferredTaxAssetsLiabilitiesNetOther_documentation_en-US" xlink:label="lab_mtg_DeferredTaxAssetsLiabilitiesNetOther" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Deferred Tax Assets (Liabilities), Net, Other</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_DeferredTaxAssetsLiabilitiesNetOther" xlink:href="mtg-20201231.xsd#mtg_DeferredTaxAssetsLiabilitiesNetOther"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_DeferredTaxAssetsLiabilitiesNetOther" xlink:to="lab_mtg_DeferredTaxAssetsLiabilitiesNetOther" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_UsTreasuryUstInterestRateMember_21188da1-b35a-4680-a79a-717f4a75289e_terseLabel_en-US" xlink:label="lab_us-gaap_UsTreasuryUstInterestRateMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">US Treasury (UST) Interest Rate</link:label>
    <link:label id="lab_us-gaap_UsTreasuryUstInterestRateMember_label_en-US" xlink:label="lab_us-gaap_UsTreasuryUstInterestRateMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">US Treasury (UST) Interest Rate [Member]</link:label>
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    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_UsTreasuryUstInterestRateMember" xlink:to="lab_us-gaap_UsTreasuryUstInterestRateMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_NetIncomeLoss_9556d6ee-b3ad-4338-bded-b84201390cc7_totalLabel_en-US" xlink:label="lab_us-gaap_NetIncomeLoss" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Net income</link:label>
    <link:label id="lab_us-gaap_NetIncomeLoss_09667153-163b-42df-99c0-66e478ec196e_terseLabel_en-US" xlink:label="lab_us-gaap_NetIncomeLoss" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Net income</link:label>
    <link:label id="lab_us-gaap_NetIncomeLoss_2d020f27-e463-49f9-b972-6c3d97766052_verboseLabel_en-US" xlink:label="lab_us-gaap_NetIncomeLoss" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Net income</link:label>
    <link:label id="lab_us-gaap_NetIncomeLoss_label_en-US" xlink:label="lab_us-gaap_NetIncomeLoss" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Net Income (Loss) Attributable to Parent</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NetIncomeLoss"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetIncomeLoss" xlink:to="lab_us-gaap_NetIncomeLoss" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract_43c73674-ee92-4d88-be54-3e33dcb1f390_terseLabel_en-US" xlink:label="lab_us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Reconciliation of effective income tax rate [Abstract]</link:label>
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    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract" xlink:to="lab_us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_IncomeTaxesPaid_3210fd5e-0900-4d35-9ba4-ffd8cb0dbdf9_terseLabel_en-US" xlink:label="lab_us-gaap_IncomeTaxesPaid" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Income taxes paid</link:label>
    <link:label id="lab_us-gaap_IncomeTaxesPaid_label_en-US" xlink:label="lab_us-gaap_IncomeTaxesPaid" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Income Taxes Paid</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxesPaid" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncomeTaxesPaid"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxesPaid" xlink:to="lab_us-gaap_IncomeTaxesPaid" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_OtherUnderwritingExpense_d84ebcf3-8192-4033-a971-ee2d8e07772c_terseLabel_en-US" xlink:label="lab_us-gaap_OtherUnderwritingExpense" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Other underwriting and operating expenses, net</link:label>
    <link:label id="lab_us-gaap_OtherUnderwritingExpense_label_en-US" xlink:label="lab_us-gaap_OtherUnderwritingExpense" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Other Underwriting Expense</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherUnderwritingExpense" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherUnderwritingExpense"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherUnderwritingExpense" xlink:to="lab_us-gaap_OtherUnderwritingExpense" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_EquitySecuritiesInvestmentSummaryMember_00d12ccf-2ca3-4266-b977-6d91aa9cdbd7_terseLabel_en-US" xlink:label="lab_us-gaap_EquitySecuritiesInvestmentSummaryMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Equity Securities</link:label>
    <link:label id="lab_us-gaap_EquitySecuritiesInvestmentSummaryMember_label_en-US" xlink:label="lab_us-gaap_EquitySecuritiesInvestmentSummaryMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Equity Securities, Investment Summary [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquitySecuritiesInvestmentSummaryMember" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EquitySecuritiesInvestmentSummaryMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EquitySecuritiesInvestmentSummaryMember" xlink:to="lab_us-gaap_EquitySecuritiesInvestmentSummaryMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_LeasesAbstract_e7119d26-6ff9-4454-b753-d565a5d6c30f_terseLabel_en-US" xlink:label="lab_us-gaap_LeasesAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Leases [Abstract]</link:label>
    <link:label id="lab_us-gaap_LeasesAbstract_label_en-US" xlink:label="lab_us-gaap_LeasesAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Leases [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LeasesAbstract" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LeasesAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LeasesAbstract" xlink:to="lab_us-gaap_LeasesAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DebtInstrumentAxis_4f7e2411-445b-4582-8629-1f66200c46ca_terseLabel_en-US" xlink:label="lab_us-gaap_DebtInstrumentAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Debt Instrument [Axis]</link:label>
    <link:label id="lab_us-gaap_DebtInstrumentAxis_label_en-US" xlink:label="lab_us-gaap_DebtInstrumentAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Debt Instrument [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentAxis" xlink:to="lab_us-gaap_DebtInstrumentAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_EquitySecuritiesFvNi_9e1bb858-af62-4432-9942-2101200b86a5_terseLabel_en-US" xlink:label="lab_us-gaap_EquitySecuritiesFvNi" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Equity securities, at fair value (cost, 2020 - $17,522; 2019 - $17,188)</link:label>
    <link:label id="lab_us-gaap_EquitySecuritiesFvNi_label_en-US" xlink:label="lab_us-gaap_EquitySecuritiesFvNi" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Equity Securities, FV-NI</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquitySecuritiesFvNi" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EquitySecuritiesFvNi"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EquitySecuritiesFvNi" xlink:to="lab_us-gaap_EquitySecuritiesFvNi" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_IncreaseDecreaseInEstimatedSeverityPrimaryDefaultsMember_43ba3f66-a499-4b2d-828a-fcc6c4e8a2e4_verboseLabel_en-US" xlink:label="lab_mtg_IncreaseDecreaseInEstimatedSeverityPrimaryDefaultsMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Increase (decrease)in estimated severity on primary delinquencies</link:label>
    <link:label id="lab_mtg_IncreaseDecreaseInEstimatedSeverityPrimaryDefaultsMember_label_en-US" xlink:label="lab_mtg_IncreaseDecreaseInEstimatedSeverityPrimaryDefaultsMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Increase Decrease in Estimated Severity Primary Defaults [Member]</link:label>
    <link:label id="lab_mtg_IncreaseDecreaseInEstimatedSeverityPrimaryDefaultsMember_documentation_en-US" xlink:label="lab_mtg_IncreaseDecreaseInEstimatedSeverityPrimaryDefaultsMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">The increase (decrease) in estimated severity on primary defaults that occurred in prior periods.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_IncreaseDecreaseInEstimatedSeverityPrimaryDefaultsMember" xlink:href="mtg-20201231.xsd#mtg_IncreaseDecreaseInEstimatedSeverityPrimaryDefaultsMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_IncreaseDecreaseInEstimatedSeverityPrimaryDefaultsMember" xlink:to="lab_mtg_IncreaseDecreaseInEstimatedSeverityPrimaryDefaultsMember" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_RealEstateAcquiredMember_2c33107b-b848-4b3c-b456-0def2dd061cd_terseLabel_en-US" xlink:label="lab_mtg_RealEstateAcquiredMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Real Estate Acquired</link:label>
    <link:label id="lab_mtg_RealEstateAcquiredMember_label_en-US" xlink:label="lab_mtg_RealEstateAcquiredMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Real Estate Acquired [Member]</link:label>
    <link:label id="lab_mtg_RealEstateAcquiredMember_documentation_en-US" xlink:label="lab_mtg_RealEstateAcquiredMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">This category includes information about real estate acquired by the entity through claim settlement.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_RealEstateAcquiredMember" xlink:href="mtg-20201231.xsd#mtg_RealEstateAcquiredMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_RealEstateAcquiredMember" xlink:to="lab_mtg_RealEstateAcquiredMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CapitalizationOfDeferredPolicyAcquisitionCostsPolicy_3d35d2b6-49ba-4dd0-8ff4-bd236d062ad8_terseLabel_en-US" xlink:label="lab_us-gaap_CapitalizationOfDeferredPolicyAcquisitionCostsPolicy" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Deferred Insurance Policy Acquisition Costs</link:label>
    <link:label id="lab_us-gaap_CapitalizationOfDeferredPolicyAcquisitionCostsPolicy_label_en-US" xlink:label="lab_us-gaap_CapitalizationOfDeferredPolicyAcquisitionCostsPolicy" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Deferred Policy Acquisition Costs, Policy [Policy Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizationOfDeferredPolicyAcquisitionCostsPolicy" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CapitalizationOfDeferredPolicyAcquisitionCostsPolicy"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CapitalizationOfDeferredPolicyAcquisitionCostsPolicy" xlink:to="lab_us-gaap_CapitalizationOfDeferredPolicyAcquisitionCostsPolicy" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPlanOtherCosts_7df57974-8407-4e2e-a376-f9504bf8fc5d_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanOtherCosts" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Other Adjustments</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanOtherCosts_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanOtherCosts" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Defined Benefit Plan, Other Cost (Credit)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanOtherCosts" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DefinedBenefitPlanOtherCosts"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanOtherCosts" xlink:to="lab_us-gaap_DefinedBenefitPlanOtherCosts" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_8a4cf143-a572-4175-b978-b846ac45ed16_terseLabel_en-US" xlink:label="lab_us-gaap_CommitmentsAndContingenciesDisclosureAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Commitments and Contingencies Disclosure [Abstract]</link:label>
    <link:label id="lab_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_label_en-US" xlink:label="lab_us-gaap_CommitmentsAndContingenciesDisclosureAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Commitments and Contingencies Disclosure [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CommitmentsAndContingenciesDisclosureAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract" xlink:to="lab_us-gaap_CommitmentsAndContingenciesDisclosureAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_srt_StatementScenarioAxis_15cf84da-3164-4a94-88aa-a83000afdcf1_terseLabel_en-US" xlink:label="lab_srt_StatementScenarioAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Scenario [Axis]</link:label>
    <link:label id="lab_srt_StatementScenarioAxis_label_en-US" xlink:label="lab_srt_StatementScenarioAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Scenario [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementScenarioAxis" xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_StatementScenarioAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_StatementScenarioAxis" xlink:to="lab_srt_StatementScenarioAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_DefinedBenefitPlanTotalAmortization_06ff1f06-daa4-43d4-a28a-34774e453ca0_totalLabel_en-US" xlink:label="lab_mtg_DefinedBenefitPlanTotalAmortization" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Total Amortization</link:label>
    <link:label id="lab_mtg_DefinedBenefitPlanTotalAmortization_label_en-US" xlink:label="lab_mtg_DefinedBenefitPlanTotalAmortization" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Defined Benefit Plan, Total Amortization</link:label>
    <link:label id="lab_mtg_DefinedBenefitPlanTotalAmortization_documentation_en-US" xlink:label="lab_mtg_DefinedBenefitPlanTotalAmortization" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Total amortization included in the amount of net periodic benefit cost that may include the following components: 1) gains or losses recognized in net periodic benefit cost; 2) transition obligation or asset recognized in net periodic benefit cost; and 3) prior service cost or credit recognized in net periodic benefit cost relating to benefit changes attributable to plan participants' prior service pursuant to a plan amendment or a plan initiation.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_DefinedBenefitPlanTotalAmortization" xlink:href="mtg-20201231.xsd#mtg_DefinedBenefitPlanTotalAmortization"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_DefinedBenefitPlanTotalAmortization" xlink:to="lab_mtg_DefinedBenefitPlanTotalAmortization" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPlanBenefitObligationBenefitsPaid_d0aa47b5-6ee0-4a7e-a459-f56f0a192b27_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanBenefitObligationBenefitsPaid" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Benefit Payments from the Fund</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanBenefitObligationBenefitsPaid_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanBenefitObligationBenefitsPaid" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Defined Benefit Plan, Benefit Obligation, Benefits Paid</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanBenefitObligationBenefitsPaid" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DefinedBenefitPlanBenefitObligationBenefitsPaid"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanBenefitObligationBenefitsPaid" xlink:to="lab_us-gaap_DefinedBenefitPlanBenefitObligationBenefitsPaid" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AllocatedShareBasedCompensationExpense_e88198f7-d920-4b8f-ad0e-7e93c18e3667_terseLabel_en-US" xlink:label="lab_us-gaap_AllocatedShareBasedCompensationExpense" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Compensation cost</link:label>
    <link:label id="lab_us-gaap_AllocatedShareBasedCompensationExpense_label_en-US" xlink:label="lab_us-gaap_AllocatedShareBasedCompensationExpense" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Share-based Payment Arrangement, Expense</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllocatedShareBasedCompensationExpense" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AllocatedShareBasedCompensationExpense"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AllocatedShareBasedCompensationExpense" xlink:to="lab_us-gaap_AllocatedShareBasedCompensationExpense" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CondensedFinancialInformationOfParentCompanyOnlyDisclosureTextBlock_94e41696-edfd-4504-a6fc-ee1e13e1c97e_verboseLabel_en-US" xlink:label="lab_us-gaap_CondensedFinancialInformationOfParentCompanyOnlyDisclosureTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">SCHEDULE II - CONDENSED FINANCIAL INFORMATION OF REGISTRANT</link:label>
    <link:label id="lab_us-gaap_CondensedFinancialInformationOfParentCompanyOnlyDisclosureTextBlock_label_en-US" xlink:label="lab_us-gaap_CondensedFinancialInformationOfParentCompanyOnlyDisclosureTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Condensed Financial Information of Parent Company Only Disclosure [Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CondensedFinancialInformationOfParentCompanyOnlyDisclosureTextBlock" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CondensedFinancialInformationOfParentCompanyOnlyDisclosureTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CondensedFinancialInformationOfParentCompanyOnlyDisclosureTextBlock" xlink:to="lab_us-gaap_CondensedFinancialInformationOfParentCompanyOnlyDisclosureTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPlanFairValueOfPlanAssets_0306fae7-5c18-4618-86e4-870db084f0ab_verboseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanFairValueOfPlanAssets" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Plan Assets at Fair Value</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanFairValueOfPlanAssets_e598de20-f807-4075-9306-034c4f63f325_periodStartLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanFairValueOfPlanAssets" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Fair Value of Plan Assets at Beginning of Year</link:label>
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    <link:label id="lab_us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsPeriodIncreaseDecrease_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsPeriodIncreaseDecrease" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Defined Benefit Plan, Plan Assets, Period Increase (Decrease)</link:label>
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    <link:label id="lab_us-gaap_CashAndCashEquivalentsMember_9baa0c1f-4437-44c6-8273-7611b6c65f82_terseLabel_en-US" xlink:label="lab_us-gaap_CashAndCashEquivalentsMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Cash equivalents</link:label>
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    <link:label id="lab_mtg_PrimaryDefaultInventoryTwelveMonthsOrMorePercentOfPrimaryDefaultInventoryInDefaultForTwelveMonthsOrMoreInDefaultForMoreThanThirtySixConsecutiveMonths_aecff343-34c9-4684-b30c-180155b0a33f_terseLabel_en-US" xlink:label="lab_mtg_PrimaryDefaultInventoryTwelveMonthsOrMorePercentOfPrimaryDefaultInventoryInDefaultForTwelveMonthsOrMoreInDefaultForMoreThanThirtySixConsecutiveMonths" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Percent of inventory in default for more than 36 consecutive months</link:label>
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    <link:label id="lab_us-gaap_PortionAtFairValueFairValueDisclosureMember_1bbf2a10-94a6-42c7-9b43-7c4a82cbc5fb_terseLabel_en-US" xlink:label="lab_us-gaap_PortionAtFairValueFairValueDisclosureMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Portion at Fair Value Measurement</link:label>
    <link:label id="lab_us-gaap_PortionAtFairValueFairValueDisclosureMember_label_en-US" xlink:label="lab_us-gaap_PortionAtFairValueFairValueDisclosureMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Portion at Fair Value Measurement [Member]</link:label>
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    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember" xlink:to="lab_us-gaap_PortionAtFairValueFairValueDisclosureMember" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_IncreaseDecreaseInProfitCommissionReceivable_a9032265-71f5-4aef-9d91-44729a6f5ea8_negatedLabel_en-US" xlink:label="lab_mtg_IncreaseDecreaseInProfitCommissionReceivable" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Profit commission receivable</link:label>
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    <link:label id="lab_mtg_IncreaseDecreaseInProfitCommissionReceivable_documentation_en-US" xlink:label="lab_mtg_IncreaseDecreaseInProfitCommissionReceivable" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">The net change during the reporting period in the amount of profit commission receivable.</link:label>
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    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_IncreaseDecreaseInProfitCommissionReceivable" xlink:to="lab_mtg_IncreaseDecreaseInProfitCommissionReceivable" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_MinimumPercentagesOfGainLossConsiderForAmortization_0b46ba39-80ac-468f-bb8e-939d088b7b64_terseLabel_en-US" xlink:label="lab_mtg_MinimumPercentagesOfGainLossConsiderForAmortization" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Minimum percentages of gain loss consider for amortization (in hundredths)</link:label>
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    <link:label id="lab_mtg_MinimumPercentagesOfGainLossConsiderForAmortization_documentation_en-US" xlink:label="lab_mtg_MinimumPercentagesOfGainLossConsiderForAmortization" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Represents minimum percentages of gain loss consider for amortization.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_MinimumPercentagesOfGainLossConsiderForAmortization" xlink:href="mtg-20201231.xsd#mtg_MinimumPercentagesOfGainLossConsiderForAmortization"/>
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    <link:label id="lab_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable_f142db2d-e057-4a1b-a748-9b25c82edc42_terseLabel_en-US" xlink:label="lab_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table]</link:label>
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    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable" xlink:to="lab_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_StockholdersEquityAbstract_987af7d7-45bf-44f0-b8f6-9949c2c9a463_verboseLabel_en-US" xlink:label="lab_us-gaap_StockholdersEquityAbstract" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Shareholders' equity:</link:label>
    <link:label id="lab_us-gaap_StockholdersEquityAbstract_fcfa93af-5f39-414d-9b5e-a3f27a75f999_terseLabel_en-US" xlink:label="lab_us-gaap_StockholdersEquityAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Shareholders&#8217; equity:</link:label>
    <link:label id="lab_us-gaap_StockholdersEquityAbstract_label_en-US" xlink:label="lab_us-gaap_StockholdersEquityAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Stockholders' Equity Attributable to Parent [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityAbstract" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StockholdersEquityAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockholdersEquityAbstract" xlink:to="lab_us-gaap_StockholdersEquityAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfComprehensiveIncomeLossTableTextBlock_bbb26770-8d93-4285-a565-252ab141fede_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfComprehensiveIncomeLossTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Other comprehensive income</link:label>
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    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfComprehensiveIncomeLossTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfComprehensiveIncomeLossTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_EquitySecuritiesFvNiUnrealizedGain_25f1a687-5fec-457d-9b29-a93818d03087_verboseLabel_en-US" xlink:label="lab_us-gaap_EquitySecuritiesFvNiUnrealizedGain" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Gross gains</link:label>
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    <link:label id="lab_srt_ScheduleOfCondensedFinancialStatementsTable_2be7fc75-4455-4e9e-a4a8-eeb779796026_terseLabel_en-US" xlink:label="lab_srt_ScheduleOfCondensedFinancialStatementsTable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Schedule of Condensed Financial Statements [Table]</link:label>
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    <link:loc xlink:type="locator" xlink:label="loc_srt_ScheduleOfCondensedFinancialStatementsTable" xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ScheduleOfCondensedFinancialStatementsTable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_ScheduleOfCondensedFinancialStatementsTable" xlink:to="lab_srt_ScheduleOfCondensedFinancialStatementsTable" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ComponentsOfDeferredTaxAssetsAndLiabilitiesAbstract_52780aa7-bfcf-4786-a7ac-a3908e464601_terseLabel_en-US" xlink:label="lab_us-gaap_ComponentsOfDeferredTaxAssetsAndLiabilitiesAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Net deferred tax assets and liabilities [Abstract]</link:label>
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    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComponentsOfDeferredTaxAssetsAndLiabilitiesAbstract" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ComponentsOfDeferredTaxAssetsAndLiabilitiesAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ComponentsOfDeferredTaxAssetsAndLiabilitiesAbstract" xlink:to="lab_us-gaap_ComponentsOfDeferredTaxAssetsAndLiabilitiesAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FairValueByBalanceSheetGroupingTextBlock_62b96c35-6417-4f55-9ad2-9875fce9a55c_terseLabel_en-US" xlink:label="lab_us-gaap_FairValueByBalanceSheetGroupingTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Schedule of carrying value and fair value of financial liabilities measured on a recurring basis</link:label>
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    <link:label id="lab_us-gaap_LiabilitiesAbstract_641774d4-195d-414e-bf90-57c188deecbd_terseLabel_en-US" xlink:label="lab_us-gaap_LiabilitiesAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Liabilities:</link:label>
    <link:label id="lab_us-gaap_LiabilitiesAbstract_label_en-US" xlink:label="lab_us-gaap_LiabilitiesAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Liabilities [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesAbstract" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LiabilitiesAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LiabilitiesAbstract" xlink:to="lab_us-gaap_LiabilitiesAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_StatutoryAccountingPracticesStatutoryAmountAvailableForDividendPaymentsWithoutRegulatoryApprovalMeasurementMeasurementPeriod_86bcf47e-1c56-4e8d-bdc3-1c29b493cd88_terseLabel_en-US" xlink:label="lab_mtg_StatutoryAccountingPracticesStatutoryAmountAvailableForDividendPaymentsWithoutRegulatoryApprovalMeasurementMeasurementPeriod" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Adjusted statutory net income measurement period</link:label>
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    <link:label id="lab_mtg_StatutoryAccountingPracticesStatutoryAmountAvailableForDividendPaymentsWithoutRegulatoryApprovalMeasurementMeasurementPeriod_documentation_en-US" xlink:label="lab_mtg_StatutoryAccountingPracticesStatutoryAmountAvailableForDividendPaymentsWithoutRegulatoryApprovalMeasurementMeasurementPeriod" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Statutory Accounting Practices, Statutory Amount Available For Dividend Payments Without Regulatory Approval, Measurement, Measurement Period</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_StatutoryAccountingPracticesStatutoryAmountAvailableForDividendPaymentsWithoutRegulatoryApprovalMeasurementMeasurementPeriod" xlink:href="mtg-20201231.xsd#mtg_StatutoryAccountingPracticesStatutoryAmountAvailableForDividendPaymentsWithoutRegulatoryApprovalMeasurementMeasurementPeriod"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_StatutoryAccountingPracticesStatutoryAmountAvailableForDividendPaymentsWithoutRegulatoryApprovalMeasurementMeasurementPeriod" xlink:to="lab_mtg_StatutoryAccountingPracticesStatutoryAmountAvailableForDividendPaymentsWithoutRegulatoryApprovalMeasurementMeasurementPeriod" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_NetProceedsCap_9d1a04f4-9671-43be-8a82-c5e4c49216e3_verboseLabel_en-US" xlink:label="lab_mtg_NetProceedsCap" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Net proceeds cap (in hundredths)</link:label>
    <link:label id="lab_mtg_NetProceedsCap_label_en-US" xlink:label="lab_mtg_NetProceedsCap" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Net proceeds cap</link:label>
    <link:label id="lab_mtg_NetProceedsCap_documentation_en-US" xlink:label="lab_mtg_NetProceedsCap" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">The percentage calculated as the average closing price of the entity's common stock times the number of the entity's outstanding shares of common stock. The average price is determined over a specified period ending before the issuance of the common stock or warrants being sold, and the number of outstanding shares is determined as of the date of the entity's most recent publicly released financial statements.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_NetProceedsCap" xlink:href="mtg-20201231.xsd#mtg_NetProceedsCap"/>
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    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue_8ec1029c-e6fa-4af9-8cbc-f3a9e1072be2_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Total fair value of restricted stock vested</link:label>
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    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DebtInstrumentRedemptionPeriodFiveMember_a7ec1365-3c03-4983-a1bf-dbd205f64f46_terseLabel_en-US" xlink:label="lab_us-gaap_DebtInstrumentRedemptionPeriodFiveMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Debt Instrument, Redemption, Period Five</link:label>
    <link:label id="lab_us-gaap_DebtInstrumentRedemptionPeriodFiveMember_label_en-US" xlink:label="lab_us-gaap_DebtInstrumentRedemptionPeriodFiveMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Debt Instrument, Redemption, Period Five [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentRedemptionPeriodFiveMember" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentRedemptionPeriodFiveMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentRedemptionPeriodFiveMember" xlink:to="lab_us-gaap_DebtInstrumentRedemptionPeriodFiveMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized_a8a25dc9-56c6-41fd-b8b3-85f4e6cee2ac_verboseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Maximum number of shares can be awarded under the plan (in shares)</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPlanServiceCost_ea3fc938-0d23-48dd-ac47-80878c1034e9_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanServiceCost" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Company Service Cost</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanServiceCost_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanServiceCost" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Defined Benefit Plan, Service Cost</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanServiceCost" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DefinedBenefitPlanServiceCost"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanServiceCost" xlink:to="lab_us-gaap_DefinedBenefitPlanServiceCost" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_PremiumsEarnedNet_c1e29206-22e8-4dfd-8c65-18665b70cae6_totalLabel_en-US" xlink:label="lab_us-gaap_PremiumsEarnedNet" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Net Amount</link:label>
    <link:label id="lab_us-gaap_PremiumsEarnedNet_label_en-US" xlink:label="lab_us-gaap_PremiumsEarnedNet" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Premiums Earned, Net</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PremiumsEarnedNet" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PremiumsEarnedNet"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PremiumsEarnedNet" xlink:to="lab_us-gaap_PremiumsEarnedNet" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_A1000IncreaseDecreaseInAverageSeverityReserveFactorMember_1fa5e174-5c30-45d8-b4ab-d4539b245cb7_terseLabel_en-US" xlink:label="lab_mtg_A1000IncreaseDecreaseInAverageSeverityReserveFactorMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">$1,000 Increase/Decrease In Average Severity Reserve Factor</link:label>
    <link:label id="lab_mtg_A1000IncreaseDecreaseInAverageSeverityReserveFactorMember_label_en-US" xlink:label="lab_mtg_A1000IncreaseDecreaseInAverageSeverityReserveFactorMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">$1,000 Increase/Decrease In Average Severity Reserve Factor [Member]</link:label>
    <link:label id="lab_mtg_A1000IncreaseDecreaseInAverageSeverityReserveFactorMember_documentation_en-US" xlink:label="lab_mtg_A1000IncreaseDecreaseInAverageSeverityReserveFactorMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">$1,000 Increase/Decrease In Average Severity Reserve Factor</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_A1000IncreaseDecreaseInAverageSeverityReserveFactorMember" xlink:href="mtg-20201231.xsd#mtg_A1000IncreaseDecreaseInAverageSeverityReserveFactorMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_A1000IncreaseDecreaseInAverageSeverityReserveFactorMember" xlink:to="lab_mtg_A1000IncreaseDecreaseInAverageSeverityReserveFactorMember" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_PooledEquityAccountsMember_4757d7af-cf85-444e-a67e-af5b7f90f6b7_terseLabel_en-US" xlink:label="lab_mtg_PooledEquityAccountsMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Pooled Equity Accounts</link:label>
    <link:label id="lab_mtg_PooledEquityAccountsMember_label_en-US" xlink:label="lab_mtg_PooledEquityAccountsMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Pooled Equity Accounts [Member]</link:label>
    <link:label id="lab_mtg_PooledEquityAccountsMember_documentation_en-US" xlink:label="lab_mtg_PooledEquityAccountsMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Funds from many individual investors that are aggregated for the purposes of investment, as in the case of a mutual or pension fund. Investors in pooled fund investments benefit from economies of scale, which allow for lower trading costs per dollar of investment, diversification and professional money management.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_PooledEquityAccountsMember" xlink:href="mtg-20201231.xsd#mtg_PooledEquityAccountsMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_PooledEquityAccountsMember" xlink:to="lab_mtg_PooledEquityAccountsMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfAllocationOfPlanAssetsTableTextBlock_4e3a0a97-5806-4990-9f21-87e938bf3324_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfAllocationOfPlanAssetsTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Year-end asset allocations of the plans</link:label>
    <link:label id="lab_us-gaap_ScheduleOfAllocationOfPlanAssetsTableTextBlock_label_en-US" xlink:label="lab_us-gaap_ScheduleOfAllocationOfPlanAssetsTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Schedule of Allocation of Plan Assets [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAllocationOfPlanAssetsTableTextBlock" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfAllocationOfPlanAssetsTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfAllocationOfPlanAssetsTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfAllocationOfPlanAssetsTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_AgingOfPrimaryDefaultInventoryAbstract_16c67aae-f3d7-4716-b314-5999a8cc8330_terseLabel_en-US" xlink:label="lab_mtg_AgingOfPrimaryDefaultInventoryAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Aging of the Primary Default Inventory [Abstract]</link:label>
    <link:label id="lab_mtg_AgingOfPrimaryDefaultInventoryAbstract_label_en-US" xlink:label="lab_mtg_AgingOfPrimaryDefaultInventoryAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Aging of the Primary Default Inventory [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_AgingOfPrimaryDefaultInventoryAbstract" xlink:href="mtg-20201231.xsd#mtg_AgingOfPrimaryDefaultInventoryAbstract"/>
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    <link:label id="lab_us-gaap_AvailableForSaleSecuritiesDebtSecurities_0d5ac5a5-7b54-480b-b19a-e7790b63cb17_verboseLabel_en-US" xlink:label="lab_us-gaap_AvailableForSaleSecuritiesDebtSecurities" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Fixed income, available-for-sale, at fair value (amortized cost, 2020 - $6,317,164; 2019 - $5,562,550)</link:label>
    <link:label id="lab_us-gaap_AvailableForSaleSecuritiesDebtSecurities_a05dfd8a-d5c4-48ea-ac5c-e7e65c7c61db_totalLabel_en-US" xlink:label="lab_us-gaap_AvailableForSaleSecuritiesDebtSecurities" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Total at end of period</link:label>
    <link:label id="lab_us-gaap_AvailableForSaleSecuritiesDebtSecurities_876441c3-4a3c-4654-b153-8c79a20c5632_terseLabel_en-US" xlink:label="lab_us-gaap_AvailableForSaleSecuritiesDebtSecurities" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Fixed income, available-for-sale</link:label>
    <link:label id="lab_us-gaap_AvailableForSaleSecuritiesDebtSecurities_3ba2dfba-6bdf-45f6-a169-9e7301392d5c_netLabel_en-US" xlink:label="lab_us-gaap_AvailableForSaleSecuritiesDebtSecurities" xlink:role="http://www.xbrl.org/2009/role/netLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Fixed income, available-for-sale, at fair value (amortized cost, 2020 &#8211; $773,881; 2019 &#8211; $287,489)</link:label>
    <link:label id="lab_us-gaap_AvailableForSaleSecuritiesDebtSecurities_label_en-US" xlink:label="lab_us-gaap_AvailableForSaleSecuritiesDebtSecurities" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Debt Securities, Available-for-sale</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtSecurities" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AvailableForSaleSecuritiesDebtSecurities"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtSecurities" xlink:to="lab_us-gaap_AvailableForSaleSecuritiesDebtSecurities" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_DefinedBenefitPlanBenefitsPaidDirectlyByCompany_c6134826-6eeb-4fdb-aea0-ea38ef6575cf_negatedLabel_en-US" xlink:label="lab_mtg_DefinedBenefitPlanBenefitsPaidDirectlyByCompany" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Benefit Payments Directly by Company</link:label>
    <link:label id="lab_mtg_DefinedBenefitPlanBenefitsPaidDirectlyByCompany_a227f9af-a066-442c-a8d6-14ca0e8b383c_negatedTerseLabel_en-US" xlink:label="lab_mtg_DefinedBenefitPlanBenefitsPaidDirectlyByCompany" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Benefit Payments paid directly by Company</link:label>
    <link:label id="lab_mtg_DefinedBenefitPlanBenefitsPaidDirectlyByCompany_label_en-US" xlink:label="lab_mtg_DefinedBenefitPlanBenefitsPaidDirectlyByCompany" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Defined Benefit Plan, Benefits Paid Directly by Company</link:label>
    <link:label id="lab_mtg_DefinedBenefitPlanBenefitsPaidDirectlyByCompany_documentation_en-US" xlink:label="lab_mtg_DefinedBenefitPlanBenefitsPaidDirectlyByCompany" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">The amount of payments made directly by the entity for which participants are entitled under a pension plan, including pension benefits, death benefits, and benefits due on termination of employment. Also includes payments made under a postretirement benefit plan, including prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. This item represents a periodic decrease to the plan obligations and a decrease to plan assets.</link:label>
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    <link:label id="lab_us-gaap_RetainedEarningsAccumulatedDeficit_f7bd1812-b39e-470b-ad4a-bed4bfa85638_terseLabel_en-US" xlink:label="lab_us-gaap_RetainedEarningsAccumulatedDeficit" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Retained earnings</link:label>
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    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsAccumulatedDeficit" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RetainedEarningsAccumulatedDeficit"/>
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    <link:label id="lab_us-gaap_PaymentsForRepurchaseOfCommonStock_b047dff9-b79d-4387-83bd-72de18001169_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_PaymentsForRepurchaseOfCommonStock" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Repurchase of common stock</link:label>
    <link:label id="lab_us-gaap_PaymentsForRepurchaseOfCommonStock_label_en-US" xlink:label="lab_us-gaap_PaymentsForRepurchaseOfCommonStock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Payments for Repurchase of Common Stock</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsForRepurchaseOfCommonStock" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PaymentsForRepurchaseOfCommonStock"/>
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    <link:label id="lab_us-gaap_OtherIncome_5c88f4e3-6558-4900-8a87-58b18881c5bd_terseLabel_en-US" xlink:label="lab_us-gaap_OtherIncome" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Other revenue</link:label>
    <link:label id="lab_us-gaap_OtherIncome_label_en-US" xlink:label="lab_us-gaap_OtherIncome" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Other Income</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherIncome" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherIncome"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherIncome" xlink:to="lab_us-gaap_OtherIncome" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_RevenueRecognitionPolicyTextBlock_eb00c8d4-2650-4d35-986c-55a8e0935651_terseLabel_en-US" xlink:label="lab_us-gaap_RevenueRecognitionPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Revenue Recognition</link:label>
    <link:label id="lab_us-gaap_RevenueRecognitionPolicyTextBlock_label_en-US" xlink:label="lab_us-gaap_RevenueRecognitionPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Revenue [Policy Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRecognitionPolicyTextBlock" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RevenueRecognitionPolicyTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RevenueRecognitionPolicyTextBlock" xlink:to="lab_us-gaap_RevenueRecognitionPolicyTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_EarningsPerShareDiluted_8c7cfb12-751f-4fbb-bc05-a5a6963aeaf5_verboseLabel_en-US" xlink:label="lab_us-gaap_EarningsPerShareDiluted" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Diluted (in dollars per share)</link:label>
    <link:label id="lab_us-gaap_EarningsPerShareDiluted_43e3d390-8cfb-4c5d-b9f5-0ef326ee0b37_terseLabel_en-US" xlink:label="lab_us-gaap_EarningsPerShareDiluted" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Diluted income per share (in dollars per share)</link:label>
    <link:label id="lab_us-gaap_EarningsPerShareDiluted_label_en-US" xlink:label="lab_us-gaap_EarningsPerShareDiluted" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Earnings Per Share, Diluted</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareDiluted" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EarningsPerShareDiluted"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EarningsPerShareDiluted" xlink:to="lab_us-gaap_EarningsPerShareDiluted" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AssumedPremiumsEarned_53a60a85-a392-427c-a6d7-959c41e58463_verboseLabel_en-US" xlink:label="lab_us-gaap_AssumedPremiumsEarned" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Premiums earned, assumed</link:label>
    <link:label id="lab_us-gaap_AssumedPremiumsEarned_c9642f3c-08cb-4059-9cc3-44302be49ce2_terseLabel_en-US" xlink:label="lab_us-gaap_AssumedPremiumsEarned" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Assumed From Other Companies</link:label>
    <link:label id="lab_us-gaap_AssumedPremiumsEarned_label_en-US" xlink:label="lab_us-gaap_AssumedPremiumsEarned" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Assumed Premiums Earned</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssumedPremiumsEarned" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AssumedPremiumsEarned"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AssumedPremiumsEarned" xlink:to="lab_us-gaap_AssumedPremiumsEarned" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfNetBenefitCostsTableTextBlock_a55cfb91-8ffc-4cff-8735-ade2da6ce290_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfNetBenefitCostsTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Components of net periodic benefit cost</link:label>
    <link:label id="lab_us-gaap_ScheduleOfNetBenefitCostsTableTextBlock_label_en-US" xlink:label="lab_us-gaap_ScheduleOfNetBenefitCostsTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Schedule of Net Benefit Costs [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfNetBenefitCostsTableTextBlock" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfNetBenefitCostsTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfNetBenefitCostsTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfNetBenefitCostsTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_srt_MinimumMember_ba5153bf-395a-4397-855f-d9d1e306faca_terseLabel_en-US" xlink:label="lab_srt_MinimumMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Minimum</link:label>
    <link:label id="lab_srt_MinimumMember_label_en-US" xlink:label="lab_srt_MinimumMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Minimum [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember" xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_MinimumMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_MinimumMember" xlink:to="lab_srt_MinimumMember" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_ReinsuranceQuotaShareReinsuranceAgreementTermsCedingRatePercentOptionOne_aad98011-e4d2-422c-be5c-912c28186b9c_terseLabel_en-US" xlink:label="lab_mtg_ReinsuranceQuotaShareReinsuranceAgreementTermsCedingRatePercentOptionOne" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Cede rate, option 1</link:label>
    <link:label id="lab_mtg_ReinsuranceQuotaShareReinsuranceAgreementTermsCedingRatePercentOptionOne_label_en-US" xlink:label="lab_mtg_ReinsuranceQuotaShareReinsuranceAgreementTermsCedingRatePercentOptionOne" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Reinsurance, Quota Share Reinsurance Agreement, Terms, Ceding Rate, Percent, Option One</link:label>
    <link:label id="lab_mtg_ReinsuranceQuotaShareReinsuranceAgreementTermsCedingRatePercentOptionOne_documentation_en-US" xlink:label="lab_mtg_ReinsuranceQuotaShareReinsuranceAgreementTermsCedingRatePercentOptionOne" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Reinsurance, Quota Share Reinsurance Agreement, Terms, Ceding Rate, Percent, Option One</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_ReinsuranceQuotaShareReinsuranceAgreementTermsCedingRatePercentOptionOne" xlink:href="mtg-20201231.xsd#mtg_ReinsuranceQuotaShareReinsuranceAgreementTermsCedingRatePercentOptionOne"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_ReinsuranceQuotaShareReinsuranceAgreementTermsCedingRatePercentOptionOne" xlink:to="lab_mtg_ReinsuranceQuotaShareReinsuranceAgreementTermsCedingRatePercentOptionOne" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ReinsurancePolicyTypeAxis_3f272da6-9713-45aa-9f98-6ab2231fa9ac_terseLabel_en-US" xlink:label="lab_us-gaap_ReinsurancePolicyTypeAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Reinsurance Policy, Type [Axis]</link:label>
    <link:label id="lab_us-gaap_ReinsurancePolicyTypeAxis_label_en-US" xlink:label="lab_us-gaap_ReinsurancePolicyTypeAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Reinsurance Policy, Type [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReinsurancePolicyTypeAxis" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ReinsurancePolicyTypeAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ReinsurancePolicyTypeAxis" xlink:to="lab_us-gaap_ReinsurancePolicyTypeAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ReinsuranceDisclosuresAbstract_3318141a-95b8-4a2f-8906-6fcee7a4adfe_terseLabel_en-US" xlink:label="lab_us-gaap_ReinsuranceDisclosuresAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Reinsurance Disclosures [Abstract]</link:label>
    <link:label id="lab_us-gaap_ReinsuranceDisclosuresAbstract_label_en-US" xlink:label="lab_us-gaap_ReinsuranceDisclosuresAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Reinsurance Disclosures [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReinsuranceDisclosuresAbstract" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ReinsuranceDisclosuresAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ReinsuranceDisclosuresAbstract" xlink:to="lab_us-gaap_ReinsuranceDisclosuresAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases_b7f674ef-f2cc-4b6d-9cd0-a044e2db7ae8_terseLabel_en-US" xlink:label="lab_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Acquisitions</link:label>
    <link:label id="lab_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases_label_en-US" xlink:label="lab_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases" xlink:to="lab_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_EntityDomain_996809d4-6c19-4d8f-8039-6321e022723d_terseLabel_en-US" xlink:label="lab_dei_EntityDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Entity [Domain]</link:label>
    <link:label id="lab_dei_EntityDomain_label_en-US" xlink:label="lab_dei_EntityDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Entity [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain" xlink:href="https://xbrl.sec.gov/dei/2020/dei-2020-01-31.xsd#dei_EntityDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityDomain" xlink:to="lab_dei_EntityDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DeferredIncomeTaxExpenseBenefit_9b5871d5-dfe2-432f-81e3-ab44faf7773a_terseLabel_en-US" xlink:label="lab_us-gaap_DeferredIncomeTaxExpenseBenefit" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Deferred Federal</link:label>
    <link:label id="lab_us-gaap_DeferredIncomeTaxExpenseBenefit_label_en-US" xlink:label="lab_us-gaap_DeferredIncomeTaxExpenseBenefit" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Deferred Income Tax Expense (Benefit)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredIncomeTaxExpenseBenefit" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DeferredIncomeTaxExpenseBenefit"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredIncomeTaxExpenseBenefit" xlink:to="lab_us-gaap_DeferredIncomeTaxExpenseBenefit" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_IncreaseDecreaseInExpectedClaimRateMember_d28fd7fc-c539-4407-8679-b36d235602c5_verboseLabel_en-US" xlink:label="lab_mtg_IncreaseDecreaseInExpectedClaimRateMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">(Decrease) in estimated claim rate on primary delinquencies</link:label>
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    <link:label id="lab_mtg_IncreaseDecreaseInExpectedClaimRateMember_documentation_en-US" xlink:label="lab_mtg_IncreaseDecreaseInExpectedClaimRateMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">The increase (decrease) in the expected claim rate on primary and/or pool defaults that occurred in prior periods.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_IncreaseDecreaseInExpectedClaimRateMember" xlink:href="mtg-20201231.xsd#mtg_IncreaseDecreaseInExpectedClaimRateMember"/>
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    <link:label id="lab_mtg_StatutoryAccountingPracticesStatutoryNetIncomeAdjustment_66ccf840-2a85-4af4-943a-18ded9807dc2_terseLabel_en-US" xlink:label="lab_mtg_StatutoryAccountingPracticesStatutoryNetIncomeAdjustment" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Reduction in statutory net income due to increase in contingency reserve</link:label>
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    <link:label id="lab_us-gaap_ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent_57b229d3-b91b-46d6-b09b-478989d647a8_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Less: Amounts reclassified from AOCL</link:label>
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    <link:label id="lab_us-gaap_IncreaseDecreaseInIncomeTaxesReceivable_4ac1f6fb-f519-4e60-a467-e41093f1a6d6_negatedLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInIncomeTaxesReceivable" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Income taxes receivable</link:label>
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    <link:label id="lab_us-gaap_IncomeTaxExpenseBenefit_8ae225f6-2d2b-44b6-886c-eb0d5f855722_terseLabel_en-US" xlink:label="lab_us-gaap_IncomeTaxExpenseBenefit" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Provision for income taxes</link:label>
    <link:label id="lab_us-gaap_IncomeTaxExpenseBenefit_80003502-f8c6-40c9-92e0-1eb4d8c3f2bd_negatedNetLabel_en-US" xlink:label="lab_us-gaap_IncomeTaxExpenseBenefit" xlink:role="http://www.xbrl.org/2009/role/negatedNetLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Income tax (expense) benefit</link:label>
    <link:label id="lab_us-gaap_IncomeTaxExpenseBenefit_211e9d5d-d29b-4c7d-b00e-618805873837_verboseLabel_en-US" xlink:label="lab_us-gaap_IncomeTaxExpenseBenefit" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Provision for income tax</link:label>
    <link:label id="lab_us-gaap_IncomeTaxExpenseBenefit_label_en-US" xlink:label="lab_us-gaap_IncomeTaxExpenseBenefit" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Income Tax Expense (Benefit)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncomeTaxExpenseBenefit"/>
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    <link:label id="lab_us-gaap_OperatingLeaseLiabilitiesPaymentsDueAbstract_8d659f91-db81-40ee-8224-02442db57f2e_terseLabel_en-US" xlink:label="lab_us-gaap_OperatingLeaseLiabilitiesPaymentsDueAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Lessee, Operating Lease, Liability, Payment, Due [Abstract]</link:label>
    <link:label id="lab_us-gaap_OperatingLeaseLiabilitiesPaymentsDueAbstract_label_en-US" xlink:label="lab_us-gaap_OperatingLeaseLiabilitiesPaymentsDueAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Lessee, Operating Lease, Liability, Payment, Due [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseLiabilitiesPaymentsDueAbstract" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OperatingLeaseLiabilitiesPaymentsDueAbstract"/>
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    <link:label id="lab_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo_label_en-US" xlink:label="lab_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Lessee, Operating Lease, Liability, Payments, Due Year Two</link:label>
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    <link:label id="lab_us-gaap_AssetsFairValueDisclosure_49eda685-2228-4399-80e6-392e8b734ab5_totalLabel_en-US" xlink:label="lab_us-gaap_AssetsFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Total assets</link:label>
    <link:label id="lab_us-gaap_AssetsFairValueDisclosure_label_en-US" xlink:label="lab_us-gaap_AssetsFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Assets, Fair Value Disclosure</link:label>
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    <link:label id="lab_us-gaap_LiabilityReserveEstimatePolicy_6abfaf7e-055a-4474-9ed0-4324c975a03e_terseLabel_en-US" xlink:label="lab_us-gaap_LiabilityReserveEstimatePolicy" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Loss Reserves</link:label>
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    <link:label id="lab_us-gaap_EquitySecuritiesFvNiCost_9112fa51-3f41-4b17-8cc7-35879919fba2_terseLabel_en-US" xlink:label="lab_us-gaap_EquitySecuritiesFvNiCost" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Equity securities, cost</link:label>
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    <link:label id="lab_mtg_QuotaShareReinsuranceAgreement2019Member_c617cc8d-f925-4e5c-aeca-7cd203170d7d_terseLabel_en-US" xlink:label="lab_mtg_QuotaShareReinsuranceAgreement2019Member" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">2019 QSR</link:label>
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    <link:label id="lab_mtg_RestrictedStockAndRestrictedStockUnitsMember_4cc3d62d-cacb-49af-8006-a9907a881f13_terseLabel_en-US" xlink:label="lab_mtg_RestrictedStockAndRestrictedStockUnitsMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Restricted Stock/Restricted Stock Units</link:label>
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    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossTax_0c9f2f74-37ca-453b-b939-d21ed24fd69e_negatedTotalLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossTax" xlink:role="http://www.xbrl.org/2009/role/negatedTotalLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Total income tax expense, net</link:label>
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    <link:label id="lab_mtg_BenefitPlanPaymentsTotalPlanPayments_2bf75c36-7d35-4767-a667-139451995c7b_terseLabel_en-US" xlink:label="lab_mtg_BenefitPlanPaymentsTotalPlanPayments" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Actual Benefit Payments for the Year Ending: Current</link:label>
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    <link:loc xlink:type="locator" xlink:label="loc_mtg_BenefitPlanPaymentsTotalPlanPayments" xlink:href="mtg-20201231.xsd#mtg_BenefitPlanPaymentsTotalPlanPayments"/>
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    <link:label id="lab_mtg_MaximumNumberOfTradingDays_dbdb248a-1ec2-40d6-962d-7dd57419cd26_verboseLabel_en-US" xlink:label="lab_mtg_MaximumNumberOfTradingDays" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Maximum number of trading days</link:label>
    <link:label id="lab_mtg_MaximumNumberOfTradingDays_label_en-US" xlink:label="lab_mtg_MaximumNumberOfTradingDays" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Maximum number of trading days</link:label>
    <link:label id="lab_mtg_MaximumNumberOfTradingDays_documentation_en-US" xlink:label="lab_mtg_MaximumNumberOfTradingDays" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">The maximum number of trading days within a specified time period that the closing sale price of the entity's common stock exceeds the prevailing conversion price of the debentures by a specified percentage.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_MaximumNumberOfTradingDays" xlink:href="mtg-20201231.xsd#mtg_MaximumNumberOfTradingDays"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_MaximumNumberOfTradingDays" xlink:to="lab_mtg_MaximumNumberOfTradingDays" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FairValueByMeasurementBasisAxis_944e4b91-f383-48ef-94ab-2f63d8fb0efa_terseLabel_en-US" xlink:label="lab_us-gaap_FairValueByMeasurementBasisAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Measurement Basis [Axis]</link:label>
    <link:label id="lab_us-gaap_FairValueByMeasurementBasisAxis_label_en-US" xlink:label="lab_us-gaap_FairValueByMeasurementBasisAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Measurement Basis [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByMeasurementBasisAxis" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_FairValueByMeasurementBasisAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueByMeasurementBasisAxis" xlink:to="lab_us-gaap_FairValueByMeasurementBasisAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_EntityIncorporationStateCountryCode_ced25dc9-7da5-44e6-bdfe-85f31c1b4ea2_terseLabel_en-US" xlink:label="lab_dei_EntityIncorporationStateCountryCode" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Entity Incorporation, State or Country Code</link:label>
    <link:label id="lab_dei_EntityIncorporationStateCountryCode_label_en-US" xlink:label="lab_dei_EntityIncorporationStateCountryCode" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Entity Incorporation, State or Country Code</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityIncorporationStateCountryCode" xlink:href="https://xbrl.sec.gov/dei/2020/dei-2020-01-31.xsd#dei_EntityIncorporationStateCountryCode"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityIncorporationStateCountryCode" xlink:to="lab_dei_EntityIncorporationStateCountryCode" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_InvestmentIncomeInvestmentExpense_42d05705-6482-4d64-8f65-0a7f32d3f3c7_negatedLabel_en-US" xlink:label="lab_us-gaap_InvestmentIncomeInvestmentExpense" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Investment expenses</link:label>
    <link:label id="lab_us-gaap_InvestmentIncomeInvestmentExpense_label_en-US" xlink:label="lab_us-gaap_InvestmentIncomeInvestmentExpense" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Investment Income, Investment Expense</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIncomeInvestmentExpense" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_InvestmentIncomeInvestmentExpense"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InvestmentIncomeInvestmentExpense" xlink:to="lab_us-gaap_InvestmentIncomeInvestmentExpense" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_QuotaShareReinsuranceAgreementsMember_da8b6dd7-c4f3-4cf6-bd15-c19f00ec1ce5_terseLabel_en-US" xlink:label="lab_mtg_QuotaShareReinsuranceAgreementsMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Quota Share Reinsurance Agreements</link:label>
    <link:label id="lab_mtg_QuotaShareReinsuranceAgreementsMember_label_en-US" xlink:label="lab_mtg_QuotaShareReinsuranceAgreementsMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Quota Share Reinsurance Agreements [Member]</link:label>
    <link:label id="lab_mtg_QuotaShareReinsuranceAgreementsMember_documentation_en-US" xlink:label="lab_mtg_QuotaShareReinsuranceAgreementsMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Quota Share Reinsurance Agreements</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_QuotaShareReinsuranceAgreementsMember" xlink:href="mtg-20201231.xsd#mtg_QuotaShareReinsuranceAgreementsMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_QuotaShareReinsuranceAgreementsMember" xlink:to="lab_mtg_QuotaShareReinsuranceAgreementsMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CashDividendsPaidToParentCompany_253d4d85-9c04-4c8e-8625-936044d85f03_terseLabel_en-US" xlink:label="lab_us-gaap_CashDividendsPaidToParentCompany" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Dividends paid to the parent company</link:label>
    <link:label id="lab_us-gaap_CashDividendsPaidToParentCompany_label_en-US" xlink:label="lab_us-gaap_CashDividendsPaidToParentCompany" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">SEC Schedule, 12-04, Cash Dividends Paid to Registrant, Subsidiaries and Equity Method Investees</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashDividendsPaidToParentCompany" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CashDividendsPaidToParentCompany"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CashDividendsPaidToParentCompany" xlink:to="lab_us-gaap_CashDividendsPaidToParentCompany" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_DeferredTaxLiabilitiesTaxDeferredExpenseCompensationandBenefitsEmployeeBenefits_d7c0d8e2-b0d0-4d8c-9b06-48b8237dc6fb_negatedTerseLabel_en-US" xlink:label="lab_mtg_DeferredTaxLiabilitiesTaxDeferredExpenseCompensationandBenefitsEmployeeBenefits" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Benefit plans</link:label>
    <link:label id="lab_mtg_DeferredTaxLiabilitiesTaxDeferredExpenseCompensationandBenefitsEmployeeBenefits_label_en-US" xlink:label="lab_mtg_DeferredTaxLiabilitiesTaxDeferredExpenseCompensationandBenefitsEmployeeBenefits" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Deferred Tax Liabilities, Tax Deferred Expense, Compensation and Benefits, Employee Benefits</link:label>
    <link:label id="lab_mtg_DeferredTaxLiabilitiesTaxDeferredExpenseCompensationandBenefitsEmployeeBenefits_documentation_en-US" xlink:label="lab_mtg_DeferredTaxLiabilitiesTaxDeferredExpenseCompensationandBenefitsEmployeeBenefits" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Deferred Tax Liabilities, Tax Deferred Expense, Compensation and Benefits, Employee Benefits</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_DeferredTaxLiabilitiesTaxDeferredExpenseCompensationandBenefitsEmployeeBenefits" xlink:href="mtg-20201231.xsd#mtg_DeferredTaxLiabilitiesTaxDeferredExpenseCompensationandBenefitsEmployeeBenefits"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_DeferredTaxLiabilitiesTaxDeferredExpenseCompensationandBenefitsEmployeeBenefits" xlink:to="lab_mtg_DeferredTaxLiabilitiesTaxDeferredExpenseCompensationandBenefitsEmployeeBenefits" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AssetsHeldInTrust_0becacca-bc49-4a5d-bbaf-612b3deb56df_terseLabel_en-US" xlink:label="lab_us-gaap_AssetsHeldInTrust" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Assets held in trust for the benefit of contractual counterparties</link:label>
    <link:label id="lab_us-gaap_AssetsHeldInTrust_label_en-US" xlink:label="lab_us-gaap_AssetsHeldInTrust" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Assets Held-in-trust</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsHeldInTrust" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AssetsHeldInTrust"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AssetsHeldInTrust" xlink:to="lab_us-gaap_AssetsHeldInTrust" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DeferredPolicyAcquisitionCosts_78564246-1135-4ac9-a465-42a8dfe1f19f_terseLabel_en-US" xlink:label="lab_us-gaap_DeferredPolicyAcquisitionCosts" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Deferred insurance policy acquisition costs</link:label>
    <link:label id="lab_us-gaap_DeferredPolicyAcquisitionCosts_label_en-US" xlink:label="lab_us-gaap_DeferredPolicyAcquisitionCosts" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Deferred Policy Acquisition Cost</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredPolicyAcquisitionCosts" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DeferredPolicyAcquisitionCosts"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredPolicyAcquisitionCosts" xlink:to="lab_us-gaap_DeferredPolicyAcquisitionCosts" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_MaximumExposureAssociatedWithOtherDiscussionsLegalProceedings_a290181f-9384-41aa-a5b3-a35ff8891732_terseLabel_en-US" xlink:label="lab_mtg_MaximumExposureAssociatedWithOtherDiscussionsLegalProceedings" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Maximum exposure to loss</link:label>
    <link:label id="lab_mtg_MaximumExposureAssociatedWithOtherDiscussionsLegalProceedings_label_en-US" xlink:label="lab_mtg_MaximumExposureAssociatedWithOtherDiscussionsLegalProceedings" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Maximum Exposure Associated With Other Discussions Legal Proceedings</link:label>
    <link:label id="lab_mtg_MaximumExposureAssociatedWithOtherDiscussionsLegalProceedings_documentation_en-US" xlink:label="lab_mtg_MaximumExposureAssociatedWithOtherDiscussionsLegalProceedings" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Estimated maximum exposure associated with other discussions and legal proceedings related to claims paying practices.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_MaximumExposureAssociatedWithOtherDiscussionsLegalProceedings" xlink:href="mtg-20201231.xsd#mtg_MaximumExposureAssociatedWithOtherDiscussionsLegalProceedings"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_MaximumExposureAssociatedWithOtherDiscussionsLegalProceedings" xlink:to="lab_mtg_MaximumExposureAssociatedWithOtherDiscussionsLegalProceedings" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_1aa3657e-37f9-428a-8e15-bcd3489edb9a_terseLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Increase (Decrease) in Stockholders' Equity [Roll Forward]</link:label>
    <link:label id="lab_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_label_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Increase (Decrease) in Stockholders' Equity [Roll Forward]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncreaseDecreaseInStockholdersEquityRollForward"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward" xlink:to="lab_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward" xlink:type="arc" order="1"/>
    <link:label id="lab_srt_RangeAxis_95bcb6a5-3959-48c0-a83b-f542c5f7a7c0_terseLabel_en-US" xlink:label="lab_srt_RangeAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Statistical Measurement [Axis]</link:label>
    <link:label id="lab_srt_RangeAxis_label_en-US" xlink:label="lab_srt_RangeAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Statistical Measurement [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis" xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_RangeAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_RangeAxis" xlink:to="lab_srt_RangeAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_PeriodPrecedingElectionToConvert_ec111a6e-0c99-4db4-838e-6f2181e7e25d_verboseLabel_en-US" xlink:label="lab_mtg_PeriodPrecedingElectionToConvert" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Period preceding election to convert</link:label>
    <link:label id="lab_mtg_PeriodPrecedingElectionToConvert_label_en-US" xlink:label="lab_mtg_PeriodPrecedingElectionToConvert" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Period preceding election to convert</link:label>
    <link:label id="lab_mtg_PeriodPrecedingElectionToConvert_documentation_en-US" xlink:label="lab_mtg_PeriodPrecedingElectionToConvert" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">The period immediately prior to an election to convert debentures during which the average price of shares traded is determined for the purpose of calculating the conversion rate.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_PeriodPrecedingElectionToConvert" xlink:href="mtg-20201231.xsd#mtg_PeriodPrecedingElectionToConvert"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_PeriodPrecedingElectionToConvert" xlink:to="lab_mtg_PeriodPrecedingElectionToConvert" xlink:type="arc" order="1"/>
    <link:label id="lab_srt_SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesTextBlock_a4fc2a71-f435-4c1f-b38e-cc5fcb3e6eba_verboseLabel_en-US" xlink:label="lab_srt_SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">SCHEDULE I - SUMMARY OF INVESTMENTS - OTHER THAN INVESTMENTS IN RELATED PARTIES</link:label>
    <link:label id="lab_srt_SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesTextBlock_label_en-US" xlink:label="lab_srt_SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesTextBlock" xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesTextBlock" xlink:to="lab_srt_SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_EntityAddressPostalZipCode_db977c09-1658-4d67-803b-d7348681778d_terseLabel_en-US" xlink:label="lab_dei_EntityAddressPostalZipCode" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Entity Address, Postal Zip Code</link:label>
    <link:label id="lab_dei_EntityAddressPostalZipCode_label_en-US" xlink:label="lab_dei_EntityAddressPostalZipCode" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Entity Address, Postal Zip Code</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressPostalZipCode" xlink:href="https://xbrl.sec.gov/dei/2020/dei-2020-01-31.xsd#dei_EntityAddressPostalZipCode"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityAddressPostalZipCode" xlink:to="lab_dei_EntityAddressPostalZipCode" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_MaximumNumberOfSharesOfCommonStockIssuableUnderAlternativePaymentMechanism_a26e40cc-ca3f-4bd3-abe2-2e639bd4c798_verboseLabel_en-US" xlink:label="lab_mtg_MaximumNumberOfSharesOfCommonStockIssuableUnderAlternativePaymentMechanism" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Maximum number of shares of common stock issuable under the Alternative Payment Mechanism (in shares)</link:label>
    <link:label id="lab_mtg_MaximumNumberOfSharesOfCommonStockIssuableUnderAlternativePaymentMechanism_label_en-US" xlink:label="lab_mtg_MaximumNumberOfSharesOfCommonStockIssuableUnderAlternativePaymentMechanism" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Maximum number of shares of common stock issuable under the Alternative Payment Mechanism</link:label>
    <link:label id="lab_mtg_MaximumNumberOfSharesOfCommonStockIssuableUnderAlternativePaymentMechanism_documentation_en-US" xlink:label="lab_mtg_MaximumNumberOfSharesOfCommonStockIssuableUnderAlternativePaymentMechanism" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">The maximum number of shares of common stock, including shares underlying qualifying warrants, that the entity may be required to issue pursuant to the Alternative Payment Mechanism under the note agreement(s).</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_MaximumNumberOfSharesOfCommonStockIssuableUnderAlternativePaymentMechanism" xlink:href="mtg-20201231.xsd#mtg_MaximumNumberOfSharesOfCommonStockIssuableUnderAlternativePaymentMechanism"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_MaximumNumberOfSharesOfCommonStockIssuableUnderAlternativePaymentMechanism" xlink:to="lab_mtg_MaximumNumberOfSharesOfCommonStockIssuableUnderAlternativePaymentMechanism" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_PrimaryDefaultInventoryTwelveMonthsOrMorePercentage_1421a039-4c22-44ca-aba2-ce07b52fa246_verboseLabel_en-US" xlink:label="lab_mtg_PrimaryDefaultInventoryTwelveMonthsOrMorePercentage" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">12 months or more (in hundredths)</link:label>
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    <link:label id="lab_mtg_PrimaryDefaultInventoryTwelveMonthsOrMorePercentage_documentation_en-US" xlink:label="lab_mtg_PrimaryDefaultInventoryTwelveMonthsOrMorePercentage" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">The percentage of loans that have been in the primary default inventory for twelve months or more as of the balance sheet date.</link:label>
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    <link:label id="lab_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger_c303c8dd-9b40-4757-9eb7-3e28ccdd8cda_terseLabel_en-US" xlink:label="lab_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">12 months or greater</link:label>
    <link:label id="lab_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger_label_en-US" xlink:label="lab_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger"/>
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    <link:label id="lab_us-gaap_EquitySecuritiesFvNiRealizedGain_a50cbd0b-d836-47d4-98d5-d64a45abb1f1_terseLabel_en-US" xlink:label="lab_us-gaap_EquitySecuritiesFvNiRealizedGain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Gross realized gains on equity securities</link:label>
    <link:label id="lab_us-gaap_EquitySecuritiesFvNiRealizedGain_label_en-US" xlink:label="lab_us-gaap_EquitySecuritiesFvNiRealizedGain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Equity Securities, FV-NI, Realized Gain</link:label>
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    <link:label id="lab_us-gaap_BasisOfAccountingPolicyPolicyTextBlock_e1cf0baf-3438-46fd-9baf-dc44ff9827e9_terseLabel_en-US" xlink:label="lab_us-gaap_BasisOfAccountingPolicyPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Basis of presentation</link:label>
    <link:label id="lab_us-gaap_BasisOfAccountingPolicyPolicyTextBlock_label_en-US" xlink:label="lab_us-gaap_BasisOfAccountingPolicyPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Basis of Accounting, Policy [Policy Text Block]</link:label>
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    <link:label id="lab_us-gaap_InsuranceLossReservesAbstract_550fdd37-7dfe-49de-9a41-731e7564e5fb_terseLabel_en-US" xlink:label="lab_us-gaap_InsuranceLossReservesAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Insurance Loss Reserves [Abstract]</link:label>
    <link:label id="lab_us-gaap_InsuranceLossReservesAbstract_label_en-US" xlink:label="lab_us-gaap_InsuranceLossReservesAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Insurance Loss Reserves [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InsuranceLossReservesAbstract" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_InsuranceLossReservesAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InsuranceLossReservesAbstract" xlink:to="lab_us-gaap_InsuranceLossReservesAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet_dccc9da5-5c7b-4730-beba-0884f326095a_terseLabel_en-US" xlink:label="lab_us-gaap_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Net reserve at beginning of year</link:label>
    <link:label id="lab_us-gaap_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet_label_en-US" xlink:label="lab_us-gaap_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Liability for Unpaid Claims and Claims Adjustment Expense, Net</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet" xlink:to="lab_us-gaap_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_EarningsPerShareBasicAbstract_4c7dc82f-155e-4282-a496-2392fc06423f_terseLabel_en-US" xlink:label="lab_us-gaap_EarningsPerShareBasicAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Basic earnings per share [Abstract]</link:label>
    <link:label id="lab_us-gaap_EarningsPerShareBasicAbstract_label_en-US" xlink:label="lab_us-gaap_EarningsPerShareBasicAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Earnings Per Share, Basic [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareBasicAbstract" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EarningsPerShareBasicAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EarningsPerShareBasicAbstract" xlink:to="lab_us-gaap_EarningsPerShareBasicAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPlanPlanAssetsTargetAllocationPercentage_5ba5abfc-7f06-47e1-9aa9-993ed6d7ce63_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanPlanAssetsTargetAllocationPercentage" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Target asset allocations (in hundredths)</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanPlanAssetsTargetAllocationPercentage_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanPlanAssetsTargetAllocationPercentage" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Defined Benefit Plan, Plan Assets, Target Allocation, Percentage</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanPlanAssetsTargetAllocationPercentage" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DefinedBenefitPlanPlanAssetsTargetAllocationPercentage"/>
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    <link:label id="lab_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlanNetPriorServiceCostCreditArisingDuringPeriodBeforeTax_bfc70b28-a0ed-46f1-b4f3-07f5cbc3461c_terseLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlanNetPriorServiceCostCreditArisingDuringPeriodBeforeTax" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Occurring during year - Prior Service Cost</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlanNetPriorServiceCostCreditArisingDuringPeriodBeforeTax_label_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlanNetPriorServiceCostCreditArisingDuringPeriodBeforeTax" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), before Tax</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlanNetPriorServiceCostCreditArisingDuringPeriodBeforeTax" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherComprehensiveIncomeDefinedBenefitPlanNetPriorServiceCostCreditArisingDuringPeriodBeforeTax"/>
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    <link:label id="lab_us-gaap_DebtDisclosureTextBlock_9daa2262-a7a8-47eb-a22b-fb551788b922_verboseLabel_en-US" xlink:label="lab_us-gaap_DebtDisclosureTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Debt</link:label>
    <link:label id="lab_us-gaap_DebtDisclosureTextBlock_label_en-US" xlink:label="lab_us-gaap_DebtDisclosureTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Debt Disclosure [Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtDisclosureTextBlock" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtDisclosureTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtDisclosureTextBlock" xlink:to="lab_us-gaap_DebtDisclosureTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_IncreaseDecreaseRelatedToPoolReservesLAEReservesAndReinsuranceMember_0c84a2e4-3148-401c-981b-d07b86818f6f_terseLabel_en-US" xlink:label="lab_mtg_IncreaseDecreaseRelatedToPoolReservesLAEReservesAndReinsuranceMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Change in estimates related to pool reserves, LAE reserves, reinsurance and other</link:label>
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    <link:label id="lab_mtg_IncreaseDecreaseRelatedToPoolReservesLAEReservesAndReinsuranceMember_documentation_en-US" xlink:label="lab_mtg_IncreaseDecreaseRelatedToPoolReservesLAEReservesAndReinsuranceMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">The decrease in losses incurred related to prior years related to pool reserves, LAE reserves, reinsurance and other.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_IncreaseDecreaseRelatedToPoolReservesLAEReservesAndReinsuranceMember" xlink:href="mtg-20201231.xsd#mtg_IncreaseDecreaseRelatedToPoolReservesLAEReservesAndReinsuranceMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_IncreaseDecreaseRelatedToPoolReservesLAEReservesAndReinsuranceMember" xlink:to="lab_mtg_IncreaseDecreaseRelatedToPoolReservesLAEReservesAndReinsuranceMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain_5c48f972-722a-4b28-8157-d80f1ab89a9b_terseLabel_en-US" xlink:label="lab_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Reclassification out of Accumulated Other Comprehensive Income [Domain]</link:label>
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    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain" xlink:to="lab_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AccountingStandardsUpdate201601Member_f864af56-f9a0-4f31-991b-66c94d374026_terseLabel_en-US" xlink:label="lab_us-gaap_AccountingStandardsUpdate201601Member" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">ASU 2016-01</link:label>
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    <link:label id="lab_us-gaap_CommonStockSharesAuthorized_36fff847-f909-4d0a-b78b-548eacdbc5e6_terseLabel_en-US" xlink:label="lab_us-gaap_CommonStockSharesAuthorized" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Common stock, shares authorized (in shares)</link:label>
    <link:label id="lab_us-gaap_CommonStockSharesAuthorized_label_en-US" xlink:label="lab_us-gaap_CommonStockSharesAuthorized" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Common Stock, Shares Authorized</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesAuthorized" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CommonStockSharesAuthorized"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockSharesAuthorized" xlink:to="lab_us-gaap_CommonStockSharesAuthorized" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossBeforeTax_c924ad07-1035-405b-aaa1-5d3fd28221ac_totalLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossBeforeTax" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Total other comprehensive income (loss)</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossBeforeTax_label_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossBeforeTax" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Other Comprehensive Income (Loss), before Tax</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossBeforeTax" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossBeforeTax"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossBeforeTax" xlink:to="lab_us-gaap_OtherComprehensiveIncomeLossBeforeTax" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_PrimaryDefaultInventoryPercentage_f40bf079-32ff-4952-a63d-997396f35410_totalLabel_en-US" xlink:label="lab_mtg_PrimaryDefaultInventoryPercentage" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Total primary default inventory (in hundredths)</link:label>
    <link:label id="lab_mtg_PrimaryDefaultInventoryPercentage_label_en-US" xlink:label="lab_mtg_PrimaryDefaultInventoryPercentage" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Primary default inventory, Percentage</link:label>
    <link:label id="lab_mtg_PrimaryDefaultInventoryPercentage_documentation_en-US" xlink:label="lab_mtg_PrimaryDefaultInventoryPercentage" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">The percentage of loans in the primary default inventory.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_PrimaryDefaultInventoryPercentage" xlink:href="mtg-20201231.xsd#mtg_PrimaryDefaultInventoryPercentage"/>
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    <link:label id="lab_mtg_EffectOfQuotaShareReinsuranceAgreementsOnPremiumsEarnedAndLossesIncurredTableTextBlock_838a6a76-155b-4fd7-a2f7-327f1446d4f3_terseLabel_en-US" xlink:label="lab_mtg_EffectOfQuotaShareReinsuranceAgreementsOnPremiumsEarnedAndLossesIncurredTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Quota share reinsurance agreements on premiums earned and losses incurred</link:label>
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    <link:label id="lab_us-gaap_StateAndLocalJurisdictionMember_57581584-5192-4cf4-ac83-bd7277a2fa6e_terseLabel_en-US" xlink:label="lab_us-gaap_StateAndLocalJurisdictionMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">State tax authorities</link:label>
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    <link:label id="lab_us-gaap_ProceedsFromIssuanceOfSeniorLongTermDebt_6327c290-7f41-4555-882d-8c58e63839cc_terseLabel_en-US" xlink:label="lab_us-gaap_ProceedsFromIssuanceOfSeniorLongTermDebt" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Proceeds from issuance of debt</link:label>
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    <link:label id="lab_mtg_DividendDistributionOfInterestOfConvertibleJuniorSubordinatedDebentures_df3b6138-6284-4581-86ec-e1de388c482f_terseLabel_en-US" xlink:label="lab_mtg_DividendDistributionOfInterestOfConvertibleJuniorSubordinatedDebentures" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Dividend to parent, distribution of interest in 9% Debentures</link:label>
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    <link:label id="lab_us-gaap_LesseeOperatingLeaseTermOfContract_a450c263-7c2b-43f6-a9b4-8b7a5f6b7dba_terseLabel_en-US" xlink:label="lab_us-gaap_LesseeOperatingLeaseTermOfContract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Remaining term of operating leases (in years)</link:label>
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    <link:label id="lab_mtg_MinimumNumberOfPaymentsPastDueToBeInDefault_documentation_en-US" xlink:label="lab_mtg_MinimumNumberOfPaymentsPastDueToBeInDefault" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">The number of payments past due in order for such loans to be considered in default.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_MinimumNumberOfPaymentsPastDueToBeInDefault" xlink:href="mtg-20201231.xsd#mtg_MinimumNumberOfPaymentsPastDueToBeInDefault"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_MinimumNumberOfPaymentsPastDueToBeInDefault" xlink:to="lab_mtg_MinimumNumberOfPaymentsPastDueToBeInDefault" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_bf8d8568-fa05-4d1c-8ac3-20a8882d4f2d_terseLabel_en-US" xlink:label="lab_us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Fair Value, Measurements, Fair Value Hierarchy [Domain]</link:label>
    <link:label id="lab_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_label_en-US" xlink:label="lab_us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Fair Value Hierarchy and NAV [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:to="lab_us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTableTextBlock_f7d5f3c4-6af4-4ac1-ac59-62fb20f38d0d_terseLabel_en-US" xlink:label="lab_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Reclassification out of accumulated other comprehensive income</link:label>
    <link:label id="lab_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTableTextBlock_label_en-US" xlink:label="lab_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Reclassification out of Accumulated Other Comprehensive Income [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTableTextBlock" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTableTextBlock" xlink:to="lab_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense_2abd88cd-8d5b-4687-b8be-e23eda9e9518_terseLabel_en-US" xlink:label="lab_us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Current year</link:label>
    <link:label id="lab_us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense_label_en-US" xlink:label="lab_us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Current Year Claims and Claims Adjustment Expense</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense" xlink:to="lab_us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_RetirementPlanTypeDomain_8e7f3f8c-87dc-4301-b931-4f94164fc4e4_terseLabel_en-US" xlink:label="lab_us-gaap_RetirementPlanTypeDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Retirement Plan Type [Domain]</link:label>
    <link:label id="lab_us-gaap_RetirementPlanTypeDomain_label_en-US" xlink:label="lab_us-gaap_RetirementPlanTypeDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Retirement Plan Type [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetirementPlanTypeDomain" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RetirementPlanTypeDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RetirementPlanTypeDomain" xlink:to="lab_us-gaap_RetirementPlanTypeDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_OtherAssetsFairValueDisclosure_c0f19ee4-50c9-467e-bee7-93407b8d9175_terseLabel_en-US" xlink:label="lab_us-gaap_OtherAssetsFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Cash Equivalents</link:label>
    <link:label id="lab_us-gaap_OtherAssetsFairValueDisclosure_label_en-US" xlink:label="lab_us-gaap_OtherAssetsFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Other Assets, Fair Value Disclosure</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherAssetsFairValueDisclosure" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherAssetsFairValueDisclosure"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherAssetsFairValueDisclosure" xlink:to="lab_us-gaap_OtherAssetsFairValueDisclosure" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_MinimumNumberOfConsecutiveInterestPeriodsForWhichInterestPaymentsMayBeDeferred_695d42d8-cf23-4c67-83c9-88b28c539a8d_verboseLabel_en-US" xlink:label="lab_mtg_MinimumNumberOfConsecutiveInterestPeriodsForWhichInterestPaymentsMayBeDeferred" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Minimum number of consecutive interest periods for which interest payments may be deferred</link:label>
    <link:label id="lab_mtg_MinimumNumberOfConsecutiveInterestPeriodsForWhichInterestPaymentsMayBeDeferred_label_en-US" xlink:label="lab_mtg_MinimumNumberOfConsecutiveInterestPeriodsForWhichInterestPaymentsMayBeDeferred" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Minimum number of consecutive interest periods for which interest payments may be deferred</link:label>
    <link:label id="lab_mtg_MinimumNumberOfConsecutiveInterestPeriodsForWhichInterestPaymentsMayBeDeferred_documentation_en-US" xlink:label="lab_mtg_MinimumNumberOfConsecutiveInterestPeriodsForWhichInterestPaymentsMayBeDeferred" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">The minimum number of consecutive interest periods for which interest payments may be deferred pursuant to an optional deferral provision under the note agreement(s).</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_MinimumNumberOfConsecutiveInterestPeriodsForWhichInterestPaymentsMayBeDeferred" xlink:href="mtg-20201231.xsd#mtg_MinimumNumberOfConsecutiveInterestPeriodsForWhichInterestPaymentsMayBeDeferred"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_MinimumNumberOfConsecutiveInterestPeriodsForWhichInterestPaymentsMayBeDeferred" xlink:to="lab_mtg_MinimumNumberOfConsecutiveInterestPeriodsForWhichInterestPaymentsMayBeDeferred" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateAmortizedCost_6f57a692-7f12-467a-8e81-67e888f1f95d_verboseLabel_en-US" xlink:label="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateAmortizedCost" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Debt securities without single maturity date</link:label>
    <link:label id="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateAmortizedCost_label_en-US" xlink:label="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateAmortizedCost" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Debt Securities, Available-for-sale, Maturity, without Single Maturity Date, Amortized Cost</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateAmortizedCost" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateAmortizedCost"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateAmortizedCost" xlink:to="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateAmortizedCost" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ReinsuranceRetentionPolicyAmountRetained_338f5396-b798-459d-86ed-7706068e60a5_terseLabel_en-US" xlink:label="lab_us-gaap_ReinsuranceRetentionPolicyAmountRetained" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Remaining First Layer Retention</link:label>
    <link:label id="lab_us-gaap_ReinsuranceRetentionPolicyAmountRetained_label_en-US" xlink:label="lab_us-gaap_ReinsuranceRetentionPolicyAmountRetained" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Reinsurance Retention Policy, Amount Retained</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReinsuranceRetentionPolicyAmountRetained" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ReinsuranceRetentionPolicyAmountRetained"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ReinsuranceRetentionPolicyAmountRetained" xlink:to="lab_us-gaap_ReinsuranceRetentionPolicyAmountRetained" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_dbcda925-3755-41b4-9055-b4f804ce78ee_terseLabel_en-US" xlink:label="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Weighted-average period for recognition of compensation cost</link:label>
    <link:label id="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_label_en-US" xlink:label="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1" xlink:to="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_PrimaryDefaultInventoryCures_a76cc0ef-4707-4cba-ad7a-7cc1774c1c02_negatedTerseLabel_en-US" xlink:label="lab_mtg_PrimaryDefaultInventoryCures" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Cures</link:label>
    <link:label id="lab_mtg_PrimaryDefaultInventoryCures_label_en-US" xlink:label="lab_mtg_PrimaryDefaultInventoryCures" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Primary Default Inventory, Cures</link:label>
    <link:label id="lab_mtg_PrimaryDefaultInventoryCures_documentation_en-US" xlink:label="lab_mtg_PrimaryDefaultInventoryCures" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Deductions from the primary default inventory resulting from loans in default being brought current.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_PrimaryDefaultInventoryCures" xlink:href="mtg-20201231.xsd#mtg_PrimaryDefaultInventoryCures"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_PrimaryDefaultInventoryCures" xlink:to="lab_mtg_PrimaryDefaultInventoryCures" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AccountingPoliciesAbstract_1194d3f0-b7a2-47e9-9809-4ce255f53bbc_terseLabel_en-US" xlink:label="lab_us-gaap_AccountingPoliciesAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Accounting Policies [Abstract]</link:label>
    <link:label id="lab_us-gaap_AccountingPoliciesAbstract_label_en-US" xlink:label="lab_us-gaap_AccountingPoliciesAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Accounting Policies [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountingPoliciesAbstract" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AccountingPoliciesAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccountingPoliciesAbstract" xlink:to="lab_us-gaap_AccountingPoliciesAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_EntityAddressCityOrTown_28912673-a669-49c9-9958-3a8592e093ed_terseLabel_en-US" xlink:label="lab_dei_EntityAddressCityOrTown" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Entity Address, City or Town</link:label>
    <link:label id="lab_dei_EntityAddressCityOrTown_label_en-US" xlink:label="lab_dei_EntityAddressCityOrTown" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Entity Address, City or Town</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressCityOrTown" xlink:href="https://xbrl.sec.gov/dei/2020/dei-2020-01-31.xsd#dei_EntityAddressCityOrTown"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityAddressCityOrTown" xlink:to="lab_dei_EntityAddressCityOrTown" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_PercentageOfFairValueToAmortizedCostSecuritiesinUnrealizedLossPosition_b9b28e3c-2ea0-4614-9e4d-7721014825e5_terseLabel_en-US" xlink:label="lab_mtg_PercentageOfFairValueToAmortizedCostSecuritiesinUnrealizedLossPosition" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">For securities in an unrealized loss position, percentage of fair value to amortized cost (in hundredths)</link:label>
    <link:label id="lab_mtg_PercentageOfFairValueToAmortizedCostSecuritiesinUnrealizedLossPosition_label_en-US" xlink:label="lab_mtg_PercentageOfFairValueToAmortizedCostSecuritiesinUnrealizedLossPosition" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Percentage Of Fair Value To Amortized Cost Securities in Unrealized Loss Position</link:label>
    <link:label id="lab_mtg_PercentageOfFairValueToAmortizedCostSecuritiesinUnrealizedLossPosition_documentation_en-US" xlink:label="lab_mtg_PercentageOfFairValueToAmortizedCostSecuritiesinUnrealizedLossPosition" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">The percentage of total fair value amount to total amortized cost amount of the company's securities in an unrealized loss position.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_PercentageOfFairValueToAmortizedCostSecuritiesinUnrealizedLossPosition" xlink:href="mtg-20201231.xsd#mtg_PercentageOfFairValueToAmortizedCostSecuritiesinUnrealizedLossPosition"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_PercentageOfFairValueToAmortizedCostSecuritiesinUnrealizedLossPosition" xlink:to="lab_mtg_PercentageOfFairValueToAmortizedCostSecuritiesinUnrealizedLossPosition" xlink:type="arc" order="1"/>
    <link:label id="lab_srt_SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesAbstract_bc0f79ee-1080-4207-bdaf-78f0028db5c9_terseLabel_en-US" xlink:label="lab_srt_SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Abstract]</link:label>
    <link:label id="lab_srt_SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesAbstract_label_en-US" xlink:label="lab_srt_SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesAbstract" xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesAbstract" xlink:to="lab_srt_SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_ParentheticalInformationAbstract_52d0a953-6e22-4a90-bcc7-92edb75869e1_terseLabel_en-US" xlink:label="lab_mtg_ParentheticalInformationAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Parenthetical information [Abstract]</link:label>
    <link:label id="lab_mtg_ParentheticalInformationAbstract_label_en-US" xlink:label="lab_mtg_ParentheticalInformationAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Parenthetical information [Abstract]</link:label>
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    <link:label id="lab_mtg_DirectDomesticPrimaryRiskInForce_9998003e-cfb7-4bc4-b531-94d2de1761e6_verboseLabel_en-US" xlink:label="lab_mtg_DirectDomesticPrimaryRiskInForce" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Direct domestic primary risk in force</link:label>
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    <link:label id="lab_mtg_DirectDomesticPrimaryRiskInForce_documentation_en-US" xlink:label="lab_mtg_DirectDomesticPrimaryRiskInForce" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">The insurance in force multiplied by the insurance coverage percentage.</link:label>
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    <link:label id="lab_dei_EntityFilerCategory_89514c8e-1b08-4a2a-9658-13d445c656e8_terseLabel_en-US" xlink:label="lab_dei_EntityFilerCategory" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Entity Filer Category</link:label>
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    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_d8430334-565f-4614-b666-be6e73093324_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Shares available for future grants (in shares)</link:label>
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    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant"/>
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    <link:label id="lab_us-gaap_DebtInstrumentRedemptionPeriodTwoMember_f9851d88-6749-403a-8210-edf822eed593_terseLabel_en-US" xlink:label="lab_us-gaap_DebtInstrumentRedemptionPeriodTwoMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Debt Instrument, Redemption, Period Two</link:label>
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    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentRedemptionPeriodTwoMember" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentRedemptionPeriodTwoMember"/>
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    <link:label id="lab_us-gaap_ReinsuranceRetentionPolicyTableTextBlock_b2aa0a20-288a-4ef7-b0e0-d8bcd4da2fc2_terseLabel_en-US" xlink:label="lab_us-gaap_ReinsuranceRetentionPolicyTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Reinsurance retention policy</link:label>
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    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReinsuranceRetentionPolicyTableTextBlock" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ReinsuranceRetentionPolicyTableTextBlock"/>
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    <link:label id="lab_us-gaap_FederalHomeLoanBankAdvancesGeneralDebtObligationsDisclosuresCollateralPledged1_9fcd5afa-c3e5-4a5e-8eef-314627f6649b_terseLabel_en-US" xlink:label="lab_us-gaap_FederalHomeLoanBankAdvancesGeneralDebtObligationsDisclosuresCollateralPledged1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Collateral pledged for FHLB advance</link:label>
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    <link:label id="lab_mtg_ReinsuranceRetentionPolicyPercentOfTotalTrustAssetsInvestedInCashOrDirectU.S.FederalGovernmentObligations_b0a525ae-3c78-43e1-a9c7-24b15939e8db_terseLabel_en-US" xlink:label="lab_mtg_ReinsuranceRetentionPolicyPercentOfTotalTrustAssetsInvestedInCashOrDirectU.S.FederalGovernmentObligations" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Percent of total trust assets invested in cash or direct U.S. federal government obligations</link:label>
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    <link:label id="lab_us-gaap_USStatesAndPoliticalSubdivisionsMember_461a5d8b-56b8-45e5-810d-bd9abc024d66_terseLabel_en-US" xlink:label="lab_us-gaap_USStatesAndPoliticalSubdivisionsMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Obligations of U.S. states and political subdivisions</link:label>
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    <link:label id="lab_us-gaap_USStatesAndPoliticalSubdivisionsMember_label_en-US" xlink:label="lab_us-gaap_USStatesAndPoliticalSubdivisionsMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">US States and Political Subdivisions Debt Securities [Member]</link:label>
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    <link:label id="lab_dei_EntityAddressAddressLine1_281a9dff-1917-4746-95ec-2d4c055670fb_terseLabel_en-US" xlink:label="lab_dei_EntityAddressAddressLine1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Entity Address, Address Line One</link:label>
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    <link:label id="lab_us-gaap_CollateralizedLoanObligationsMember_c2b97d15-458f-45cc-9452-6a70f6111117_terseLabel_en-US" xlink:label="lab_us-gaap_CollateralizedLoanObligationsMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Collateralized loan obligations</link:label>
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    <link:label id="lab_dei_EntityEmergingGrowthCompany_bda88ec2-3420-477f-8c06-0dc465a61a94_terseLabel_en-US" xlink:label="lab_dei_EntityEmergingGrowthCompany" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Entity Emerging Growth Company</link:label>
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    <link:label id="lab_us-gaap_DirectPremiumsEarned_09b0ff73-97cf-4112-b046-c7e846c12514_verboseLabel_en-US" xlink:label="lab_us-gaap_DirectPremiumsEarned" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Premiums earned, direct</link:label>
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    <link:label id="lab_srt_ScenarioForecastMember_a45cc911-b8a5-4233-8491-7f8c1dfff6d8_terseLabel_en-US" xlink:label="lab_srt_ScenarioForecastMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Forecast</link:label>
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    <link:label id="lab_us-gaap_DebtInstrumentRedemptionPeriodAxis_97fba295-586c-4a84-81a7-2b9b1d57af82_terseLabel_en-US" xlink:label="lab_us-gaap_DebtInstrumentRedemptionPeriodAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Debt Instrument, Redemption, Period [Axis]</link:label>
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    <link:label id="lab_us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember_b59b43ae-35ed-4565-aa62-fa83a294a67e_terseLabel_en-US" xlink:label="lab_us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Other Postretirement Benefit Plan</link:label>
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    <link:label id="lab_mtg_SummaryOfRestrictedStockOrRestrictedStockUnitActivityAbstract_c2d8f626-c416-4792-947b-650b4f197246_terseLabel_en-US" xlink:label="lab_mtg_SummaryOfRestrictedStockOrRestrictedStockUnitActivityAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Summary of restricted stock or restricted stock unit activity [Abstract]</link:label>
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    <link:label id="lab_us-gaap_TreasuryStockValueAcquiredCostMethod_dc6c9992-80ee-4143-83af-ca573d3896d0_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_TreasuryStockValueAcquiredCostMethod" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Purchases of common stock</link:label>
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    <link:label id="lab_mtg_HomeRe20201Member_2e69bb46-3116-46a7-93ac-2957dee71bb2_terseLabel_en-US" xlink:label="lab_mtg_HomeRe20201Member" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Home Re 2020-1</link:label>
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    <link:label id="lab_us-gaap_BenefitsLossesAndExpensesAbstract_5834052e-9500-4e7e-b0cd-402bda0c1629_verboseLabel_en-US" xlink:label="lab_us-gaap_BenefitsLossesAndExpensesAbstract" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Losses and expenses:</link:label>
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    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets"/>
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    <link:label id="lab_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_354efe05-472b-4239-b7fe-32a04752ffbb_verboseLabel_en-US" xlink:label="lab_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Weighted average common shares outstanding - diluted (in shares)</link:label>
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    <link:label id="lab_us-gaap_PolicyholderBenefitsAndClaimsIncurredNetAbstract_226b1922-3fe3-4074-849a-4b97c68c5abf_terseLabel_en-US" xlink:label="lab_us-gaap_PolicyholderBenefitsAndClaimsIncurredNetAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Policyholder Benefits and Claims Incurred, Net [Abstract]</link:label>
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    <link:label id="lab_mtg_OnePercentagePointIncreaseDecreaseInAverageClaimRateReserveFactorMember_b6cdf78b-769c-44d0-aa81-39e3015c454d_terseLabel_en-US" xlink:label="lab_mtg_OnePercentagePointIncreaseDecreaseInAverageClaimRateReserveFactorMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">One Percentage Point Increase/Decrease In Average Claim Rate Reserve Factor</link:label>
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    <link:label id="lab_mtg_PercentofinternationalmutualfundsequityallocationincompaniesprimarilybasedinEuropeandPacificBasin_2cfaed7a-cb42-45ff-a56c-ca9e496c6a06_verboseLabel_en-US" xlink:label="lab_mtg_PercentofinternationalmutualfundsequityallocationincompaniesprimarilybasedinEuropeandPacificBasin" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Percent of international mutual funds equity allocation in companies primarily based in Europe and the Pacific Basin (in hundredths)</link:label>
    <link:label id="lab_mtg_PercentofinternationalmutualfundsequityallocationincompaniesprimarilybasedinEuropeandPacificBasin_label_en-US" xlink:label="lab_mtg_PercentofinternationalmutualfundsequityallocationincompaniesprimarilybasedinEuropeandPacificBasin" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Percent of international mutual funds equity allocation in companies primarily based in Europe and Pacific Basin</link:label>
    <link:label id="lab_mtg_PercentofinternationalmutualfundsequityallocationincompaniesprimarilybasedinEuropeandPacificBasin_documentation_en-US" xlink:label="lab_mtg_PercentofinternationalmutualfundsequityallocationincompaniesprimarilybasedinEuropeandPacificBasin" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">The investment in international mutual funds primarily based in Europe and the Pacific Basin, as a percentage of the equity investments range.</link:label>
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    <link:label id="lab_mtg_RollforwardOfPrimaryDefaultInventoryTableTextBlock_41d75db9-bae6-420e-989a-1a70fbf12954_terseLabel_en-US" xlink:label="lab_mtg_RollforwardOfPrimaryDefaultInventoryTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Rollforward of delinquent inventory roll-forward</link:label>
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    <link:label id="lab_mtg_RollforwardOfPrimaryDefaultInventoryTableTextBlock_documentation_en-US" xlink:label="lab_mtg_RollforwardOfPrimaryDefaultInventoryTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Tabular disclosure of the activity related to loans in the primary default inventory.</link:label>
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    <link:label id="lab_us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperationsAbstract_4e80a086-7631-4b5c-a4cb-483531306a85_terseLabel_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperationsAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Cash flows from financing activities:</link:label>
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    <link:label id="lab_us-gaap_AccruedInvestmentIncomeReceivable_179469bf-6b03-44f8-a83b-6fd4513f8235_terseLabel_en-US" xlink:label="lab_us-gaap_AccruedInvestmentIncomeReceivable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Accrued investment income</link:label>
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    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccruedInvestmentIncomeReceivable" xlink:to="lab_us-gaap_AccruedInvestmentIncomeReceivable" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_c4e06008-43fb-48d8-86b7-e571c30abb68_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Debt Securities, Available-for-sale [Line Items]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_label_en-US" xlink:label="lab_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Debt Securities, Available-for-sale [Line Items]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems" xlink:to="lab_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_Assets_9366126c-56d7-450f-8456-60456ac3ee92_totalLabel_en-US" xlink:label="lab_us-gaap_Assets" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Total assets</link:label>
    <link:label id="lab_us-gaap_Assets_label_en-US" xlink:label="lab_us-gaap_Assets" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Assets</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_Assets"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_Assets" xlink:to="lab_us-gaap_Assets" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_RealEstateMember_b1101595-87e7-4246-91ca-093ff9a80308_terseLabel_en-US" xlink:label="lab_us-gaap_RealEstateMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Real Estate</link:label>
    <link:label id="lab_us-gaap_RealEstateMember_label_en-US" xlink:label="lab_us-gaap_RealEstateMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Real Estate [Member]</link:label>
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    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RealEstateMember" xlink:to="lab_us-gaap_RealEstateMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_BenefitsLossesAndExpenses_2df5dacf-1d28-4c0f-9275-3a7b83401907_totalLabel_en-US" xlink:label="lab_us-gaap_BenefitsLossesAndExpenses" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Total losses and expenses</link:label>
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    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BenefitsLossesAndExpenses" xlink:to="lab_us-gaap_BenefitsLossesAndExpenses" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_EntityAddressStateOrProvince_4fb165bb-9cfe-4161-a12f-a9f11f1363c7_terseLabel_en-US" xlink:label="lab_dei_EntityAddressStateOrProvince" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Entity Address, State or Province</link:label>
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    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityAddressStateOrProvince" xlink:to="lab_dei_EntityAddressStateOrProvince" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_PremiumRefundLiabilityExpectedClaimPayments_184c012c-a9bb-4650-9b7d-83c9951c9319_terseLabel_en-US" xlink:label="lab_mtg_PremiumRefundLiabilityExpectedClaimPayments" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Premium refund liability, expected claim payments</link:label>
    <link:label id="lab_mtg_PremiumRefundLiabilityExpectedClaimPayments_label_en-US" xlink:label="lab_mtg_PremiumRefundLiabilityExpectedClaimPayments" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Premium refund liability, expected claim payments</link:label>
    <link:label id="lab_mtg_PremiumRefundLiabilityExpectedClaimPayments_documentation_en-US" xlink:label="lab_mtg_PremiumRefundLiabilityExpectedClaimPayments" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">The carrying amount for the estimate of premiums to be refunded on expected claim payments.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_PremiumRefundLiabilityExpectedClaimPayments" xlink:href="mtg-20201231.xsd#mtg_PremiumRefundLiabilityExpectedClaimPayments"/>
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    <link:label id="lab_srt_SubsidiariesMember_c2a092be-ed85-44a4-afb2-b3341817cb5b_terseLabel_en-US" xlink:label="lab_srt_SubsidiariesMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Insurance Subsidiaries</link:label>
    <link:label id="lab_srt_SubsidiariesMember_label_en-US" xlink:label="lab_srt_SubsidiariesMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Subsidiaries [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SubsidiariesMember" xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_SubsidiariesMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_SubsidiariesMember" xlink:to="lab_srt_SubsidiariesMember" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_OtherInvestedAssetsFairValueDisclosure_44b7e618-6d7b-4474-93dd-5d5ce96f6300_terseLabel_en-US" xlink:label="lab_mtg_OtherInvestedAssetsFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Other invested assets</link:label>
    <link:label id="lab_mtg_OtherInvestedAssetsFairValueDisclosure_label_en-US" xlink:label="lab_mtg_OtherInvestedAssetsFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Other Invested Assets, Fair Value Disclosure</link:label>
    <link:label id="lab_mtg_OtherInvestedAssetsFairValueDisclosure_documentation_en-US" xlink:label="lab_mtg_OtherInvestedAssetsFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Fair value portion of other invested assets.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_OtherInvestedAssetsFairValueDisclosure" xlink:href="mtg-20201231.xsd#mtg_OtherInvestedAssetsFairValueDisclosure"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_OtherInvestedAssetsFairValueDisclosure" xlink:to="lab_mtg_OtherInvestedAssetsFairValueDisclosure" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_PaymentOfOriginalIssueDiscountSeniorNotes_ca1c4ca5-1c39-436c-9fc7-a01218810f01_negatedTerseLabel_en-US" xlink:label="lab_mtg_PaymentOfOriginalIssueDiscountSeniorNotes" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Payment of original issue discount - senior notes</link:label>
    <link:label id="lab_mtg_PaymentOfOriginalIssueDiscountSeniorNotes_label_en-US" xlink:label="lab_mtg_PaymentOfOriginalIssueDiscountSeniorNotes" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Payment Of Original Issue Discount Senior Notes</link:label>
    <link:label id="lab_mtg_PaymentOfOriginalIssueDiscountSeniorNotes_documentation_en-US" xlink:label="lab_mtg_PaymentOfOriginalIssueDiscountSeniorNotes" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Payment Of Original Issue Discount Senior Notes</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_PaymentOfOriginalIssueDiscountSeniorNotes" xlink:href="mtg-20201231.xsd#mtg_PaymentOfOriginalIssueDiscountSeniorNotes"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_PaymentOfOriginalIssueDiscountSeniorNotes" xlink:to="lab_mtg_PaymentOfOriginalIssueDiscountSeniorNotes" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_SubsequentEventMember_1623874f-9a88-435e-afde-06d64503439b_terseLabel_en-US" xlink:label="lab_us-gaap_SubsequentEventMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Subsequent Event</link:label>
    <link:label id="lab_us-gaap_SubsequentEventMember_label_en-US" xlink:label="lab_us-gaap_SubsequentEventMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Subsequent Event [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventMember" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SubsequentEventMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SubsequentEventMember" xlink:to="lab_us-gaap_SubsequentEventMember" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_QuotaShareReinsuranceAgreement2021Member_e4bbc224-7aa7-4db9-bd03-552dcfb1749f_terseLabel_en-US" xlink:label="lab_mtg_QuotaShareReinsuranceAgreement2021Member" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Quota Share Reinsurance Agreement, 2021</link:label>
    <link:label id="lab_mtg_QuotaShareReinsuranceAgreement2021Member_label_en-US" xlink:label="lab_mtg_QuotaShareReinsuranceAgreement2021Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Quota Share Reinsurance Agreement, 2021 [Member]</link:label>
    <link:label id="lab_mtg_QuotaShareReinsuranceAgreement2021Member_documentation_en-US" xlink:label="lab_mtg_QuotaShareReinsuranceAgreement2021Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Quota Share Reinsurance Agreement, 2021 [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_QuotaShareReinsuranceAgreement2021Member" xlink:href="mtg-20201231.xsd#mtg_QuotaShareReinsuranceAgreement2021Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_QuotaShareReinsuranceAgreement2021Member" xlink:to="lab_mtg_QuotaShareReinsuranceAgreement2021Member" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_VariableRateDomain_30274a06-caf4-4e43-b01b-36dc50196929_terseLabel_en-US" xlink:label="lab_us-gaap_VariableRateDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Variable Rate [Domain]</link:label>
    <link:label id="lab_us-gaap_VariableRateDomain_label_en-US" xlink:label="lab_us-gaap_VariableRateDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Variable Rate [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableRateDomain" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_VariableRateDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_VariableRateDomain" xlink:to="lab_us-gaap_VariableRateDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_Risktocapitalratioofcombinedinsuranceoperationsatendofperiod_bce04cd5-2f8e-4b21-b73e-4a31d4545cf4_terseLabel_en-US" xlink:label="lab_mtg_Risktocapitalratioofcombinedinsuranceoperationsatendofperiod" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Risk to capital ratio of combined insurance operations at end of period</link:label>
    <link:label id="lab_mtg_Risktocapitalratioofcombinedinsuranceoperationsatendofperiod_label_en-US" xlink:label="lab_mtg_Risktocapitalratioofcombinedinsuranceoperationsatendofperiod" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Risk to capital ratio of combined insurance operations at end of period</link:label>
    <link:label id="lab_mtg_Risktocapitalratioofcombinedinsuranceoperationsatendofperiod_documentation_en-US" xlink:label="lab_mtg_Risktocapitalratioofcombinedinsuranceoperationsatendofperiod" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">The risk-to-capital ratio of the entity's combined insurance operations as of the end of the reporting period.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_Risktocapitalratioofcombinedinsuranceoperationsatendofperiod" xlink:href="mtg-20201231.xsd#mtg_Risktocapitalratioofcombinedinsuranceoperationsatendofperiod"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_Risktocapitalratioofcombinedinsuranceoperationsatendofperiod" xlink:to="lab_mtg_Risktocapitalratioofcombinedinsuranceoperationsatendofperiod" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_UnderwritingAndOtherExpensesNet_ecb4c9c9-4cbe-4765-a9f2-39318cac7a3a_terseLabel_en-US" xlink:label="lab_mtg_UnderwritingAndOtherExpensesNet" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Underwriting and other expenses, net</link:label>
    <link:label id="lab_mtg_UnderwritingAndOtherExpensesNet_label_en-US" xlink:label="lab_mtg_UnderwritingAndOtherExpensesNet" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Underwriting and other expenses, net</link:label>
    <link:label id="lab_mtg_UnderwritingAndOtherExpensesNet_documentation_en-US" xlink:label="lab_mtg_UnderwritingAndOtherExpensesNet" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Amount of underwriting and other expenses of the entity including change in premium deficiency reserve, amortization of deferred policy acquisition costs, other underwriting and operating expenses and interest expense.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_UnderwritingAndOtherExpensesNet" xlink:href="mtg-20201231.xsd#mtg_UnderwritingAndOtherExpensesNet"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_UnderwritingAndOtherExpensesNet" xlink:to="lab_mtg_UnderwritingAndOtherExpensesNet" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_TreasuryStockSharesAcquired_9f115813-358f-4062-bcba-2838b78a67f9_terseLabel_en-US" xlink:label="lab_us-gaap_TreasuryStockSharesAcquired" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Shares repurchased during period (in shares)</link:label>
    <link:label id="lab_us-gaap_TreasuryStockSharesAcquired_label_en-US" xlink:label="lab_us-gaap_TreasuryStockSharesAcquired" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Treasury Stock, Shares, Acquired</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockSharesAcquired" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_TreasuryStockSharesAcquired"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TreasuryStockSharesAcquired" xlink:to="lab_us-gaap_TreasuryStockSharesAcquired" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_FivePointSevenFivePercentSeniorNotesMember_8779572c-ecb8-4256-b44d-d7cf735e204a_terseLabel_en-US" xlink:label="lab_mtg_FivePointSevenFivePercentSeniorNotesMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">5.75% Senior Notes due 2023</link:label>
    <link:label id="lab_mtg_FivePointSevenFivePercentSeniorNotesMember_label_en-US" xlink:label="lab_mtg_FivePointSevenFivePercentSeniorNotesMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Five Point Seven Five Percent Senior Notes [Member]</link:label>
    <link:label id="lab_mtg_FivePointSevenFivePercentSeniorNotesMember_documentation_en-US" xlink:label="lab_mtg_FivePointSevenFivePercentSeniorNotesMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Five Point Seven Five Percent Senior Notes [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_FivePointSevenFivePercentSeniorNotesMember" xlink:href="mtg-20201231.xsd#mtg_FivePointSevenFivePercentSeniorNotesMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_FivePointSevenFivePercentSeniorNotesMember" xlink:to="lab_mtg_FivePointSevenFivePercentSeniorNotesMember" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_PrimaryDefaultInventoryClaimsReceivedInventory_259442c3-152a-444e-b7b4-a7600f704fa3_verboseLabel_en-US" xlink:label="lab_mtg_PrimaryDefaultInventoryClaimsReceivedInventory" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Primary claims received inventory included in ending default inventory</link:label>
    <link:label id="lab_mtg_PrimaryDefaultInventoryClaimsReceivedInventory_label_en-US" xlink:label="lab_mtg_PrimaryDefaultInventoryClaimsReceivedInventory" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Primary Default Inventory, Claims Received Inventory</link:label>
    <link:label id="lab_mtg_PrimaryDefaultInventoryClaimsReceivedInventory_documentation_en-US" xlink:label="lab_mtg_PrimaryDefaultInventoryClaimsReceivedInventory" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">The number of loans in the primary default inventory that are in the claims received inventory.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_PrimaryDefaultInventoryClaimsReceivedInventory" xlink:href="mtg-20201231.xsd#mtg_PrimaryDefaultInventoryClaimsReceivedInventory"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_PrimaryDefaultInventoryClaimsReceivedInventory" xlink:to="lab_mtg_PrimaryDefaultInventoryClaimsReceivedInventory" xlink:type="arc" order="1"/>
    <link:label id="lab_srt_SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesTable_00214fde-13db-439f-9427-ebc0061f781f_terseLabel_en-US" xlink:label="lab_srt_SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesTable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Table]</link:label>
    <link:label id="lab_srt_SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesTable_label_en-US" xlink:label="lab_srt_SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Table]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesTable" xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesTable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesTable" xlink:to="lab_srt_SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesTable" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour_877d011d-5a54-4be4-9211-5005cb00dabf_terseLabel_en-US" xlink:label="lab_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">2024</link:label>
    <link:label id="lab_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour_label_en-US" xlink:label="lab_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Lessee, Operating Lease, Liability, Payments, Due Year Four</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour" xlink:to="lab_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfGainLossOnInvestmentsTable_d69d9f47-014b-4e82-bf13-594365a6437a_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfGainLossOnInvestmentsTable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Schedule of Gain (Loss) on Securities [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfGainLossOnInvestmentsTable_label_en-US" xlink:label="lab_us-gaap_ScheduleOfGainLossOnInvestmentsTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Schedule of Gain (Loss) on Securities [Table]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfGainLossOnInvestmentsTable" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfGainLossOnInvestmentsTable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfGainLossOnInvestmentsTable" xlink:to="lab_us-gaap_ScheduleOfGainLossOnInvestmentsTable" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_InterestPayableCurrentAndNoncurrent_89ba0e4d-ca1b-4df0-91b0-6a0bb0a8110a_terseLabel_en-US" xlink:label="lab_us-gaap_InterestPayableCurrentAndNoncurrent" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Accrued interest</link:label>
    <link:label id="lab_us-gaap_InterestPayableCurrentAndNoncurrent_label_en-US" xlink:label="lab_us-gaap_InterestPayableCurrentAndNoncurrent" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Interest Payable</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestPayableCurrentAndNoncurrent" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_InterestPayableCurrentAndNoncurrent"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InterestPayableCurrentAndNoncurrent" xlink:to="lab_us-gaap_InterestPayableCurrentAndNoncurrent" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPlanAmortizationOfTransitionAssetObligation_c6183f5e-d8f5-40d9-a0c7-aeddbebbd885_negatedLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAmortizationOfTransitionAssetObligation" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Amortization of Net Transition Obligation/(Asset)</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanAmortizationOfTransitionAssetObligation_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAmortizationOfTransitionAssetObligation" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Defined Benefit Plan, Amortization of Transition Asset (Obligation)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanAmortizationOfTransitionAssetObligation" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DefinedBenefitPlanAmortizationOfTransitionAssetObligation"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanAmortizationOfTransitionAssetObligation" xlink:to="lab_us-gaap_DefinedBenefitPlanAmortizationOfTransitionAssetObligation" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_IncreaseDecreaseInDeferredPolicyAcquisitionCosts_3400da53-4c50-42ab-ba23-4caa426b4330_negatedLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInDeferredPolicyAcquisitionCosts" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Deferred insurance policy acquisition costs</link:label>
    <link:label id="lab_us-gaap_IncreaseDecreaseInDeferredPolicyAcquisitionCosts_label_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInDeferredPolicyAcquisitionCosts" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Increase (Decrease) in Deferred Policy Acquisition Costs</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInDeferredPolicyAcquisitionCosts" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncreaseDecreaseInDeferredPolicyAcquisitionCosts"/>
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    <link:label id="lab_us-gaap_LongtermDebtTypeDomain_b2e6f89c-f4b1-4eeb-8f71-cc440cc37088_terseLabel_en-US" xlink:label="lab_us-gaap_LongtermDebtTypeDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Long-term Debt, Type [Domain]</link:label>
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    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanAccumulatedBenefitObligation" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DefinedBenefitPlanAccumulatedBenefitObligation"/>
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    <link:label id="lab_us-gaap_StockholdersEquityNoteAbstract_9ffdd013-1826-49be-9000-0c75ddd72ae4_terseLabel_en-US" xlink:label="lab_us-gaap_StockholdersEquityNoteAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Stockholders' Equity Note [Abstract]</link:label>
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    <link:label id="lab_mtg_AveragePaidClaimsReductionDueToCurtailments_2bfa8668-0ea7-4f10-ab4e-a3840f2dd26e_terseLabel_en-US" xlink:label="lab_mtg_AveragePaidClaimsReductionDueToCurtailments" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Average paid claim reduction due to curtailments (in hundredths)</link:label>
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    <link:label id="lab_us-gaap_CommonStockDividendsPerShareDeclared_7e4633d3-45a8-4cde-8fe9-8b2f16a0fbd6_terseLabel_en-US" xlink:label="lab_us-gaap_CommonStockDividendsPerShareDeclared" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Common stock, dividends, per share, declared (in dollars per share)</link:label>
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    <link:label id="lab_us-gaap_EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense_b40037f6-fd0d-4d2f-9ef8-a43c97535d80_terseLabel_en-US" xlink:label="lab_us-gaap_EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Income tax benefit from compensation cost</link:label>
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    <link:label id="lab_us-gaap_ScheduleOfCausesOfIncreaseDecreaseInLiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseTextBlock_588263f9-b6ce-4a34-922a-0d30eaed7460_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfCausesOfIncreaseDecreaseInLiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Prior year development of the reserves</link:label>
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    <link:label id="lab_us-gaap_EarningsPerSharePolicyTextBlock_4ebf3bd3-421e-4269-a028-6a225b3fe645_terseLabel_en-US" xlink:label="lab_us-gaap_EarningsPerSharePolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Earnings per Share</link:label>
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    <link:label id="lab_us-gaap_PlanNameAxis_bc2496a2-fea7-4a6b-b77d-3de0e136ffc1_terseLabel_en-US" xlink:label="lab_us-gaap_PlanNameAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Plan Name [Axis]</link:label>
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    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PlanNameAxis" xlink:to="lab_us-gaap_PlanNameAxis" xlink:type="arc" order="1"/>
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    <link:label id="lab_mtg_ReinsuranceQuotaShareReinsuranceAgreementTermsAnnualLossRatioCap_c9164eee-410e-46f7-b3aa-9d1e3ea83c58_terseLabel_en-US" xlink:label="lab_mtg_ReinsuranceQuotaShareReinsuranceAgreementTermsAnnualLossRatioCap" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Annual loss ratio cap</link:label>
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    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentLineItems_50117269-8ab9-4320-86d4-3886ecf9e620_terseLabel_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Property, Plant and Equipment [Line Items]</link:label>
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    <link:label id="lab_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_c7e4fd91-f7c3-4a2e-9af9-2d5c4840987d_totalLabel_en-US" xlink:label="lab_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Total</link:label>
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    <link:label id="lab_us-gaap_FederalHomeLoanBankAdvancesMember_label_en-US" xlink:label="lab_us-gaap_FederalHomeLoanBankAdvancesMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Federal Home Loan Bank Advances [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FederalHomeLoanBankAdvancesMember" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_FederalHomeLoanBankAdvancesMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FederalHomeLoanBankAdvancesMember" xlink:to="lab_us-gaap_FederalHomeLoanBankAdvancesMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentAbstract_4692a3b4-1998-4eca-a652-7c7d6941bad0_terseLabel_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Home office and equipment [Abstract]</link:label>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentAbstract_label_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Property, Plant and Equipment [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentAbstract" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PropertyPlantAndEquipmentAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentAbstract" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_EntityCommonStockSharesOutstanding_01be8240-d3c2-4fd3-ade8-62bed777f6c2_terseLabel_en-US" xlink:label="lab_dei_EntityCommonStockSharesOutstanding" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Entity Common Stock, Shares Outstanding</link:label>
    <link:label id="lab_dei_EntityCommonStockSharesOutstanding_label_en-US" xlink:label="lab_dei_EntityCommonStockSharesOutstanding" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Entity Common Stock, Shares Outstanding</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityCommonStockSharesOutstanding" xlink:href="https://xbrl.sec.gov/dei/2020/dei-2020-01-31.xsd#dei_EntityCommonStockSharesOutstanding"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityCommonStockSharesOutstanding" xlink:to="lab_dei_EntityCommonStockSharesOutstanding" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_EquitySecuritiesMember_2055a329-dba6-4ce9-b128-bc03579b9db4_terseLabel_en-US" xlink:label="lab_us-gaap_EquitySecuritiesMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Equity securities</link:label>
    <link:label id="lab_us-gaap_EquitySecuritiesMember_label_en-US" xlink:label="lab_us-gaap_EquitySecuritiesMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Equity Securities [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquitySecuritiesMember" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EquitySecuritiesMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EquitySecuritiesMember" xlink:to="lab_us-gaap_EquitySecuritiesMember" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_PercentageOfPremiumsEarnedRequiredToBeMaintainedAsContingencyLossReserves_d2c6e39c-b93d-4e66-9bd7-cca0e6bc4bc4_verboseLabel_en-US" xlink:label="lab_mtg_PercentageOfPremiumsEarnedRequiredToBeMaintainedAsContingencyLossReserves" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Percentage of premiums earned required to be maintained as contingency loss reserves (in hundredths)</link:label>
    <link:label id="lab_mtg_PercentageOfPremiumsEarnedRequiredToBeMaintainedAsContingencyLossReserves_label_en-US" xlink:label="lab_mtg_PercentageOfPremiumsEarnedRequiredToBeMaintainedAsContingencyLossReserves" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Percentage of premiums earned required to be maintained as contingency loss reserves</link:label>
    <link:label id="lab_mtg_PercentageOfPremiumsEarnedRequiredToBeMaintainedAsContingencyLossReserves_documentation_en-US" xlink:label="lab_mtg_PercentageOfPremiumsEarnedRequiredToBeMaintainedAsContingencyLossReserves" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">The percentage of premiums earned that is required to be maintained as contingency loss reserves by mortgage guaranty insurance companies under statutory accounting practices.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_PercentageOfPremiumsEarnedRequiredToBeMaintainedAsContingencyLossReserves" xlink:href="mtg-20201231.xsd#mtg_PercentageOfPremiumsEarnedRequiredToBeMaintainedAsContingencyLossReserves"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_PercentageOfPremiumsEarnedRequiredToBeMaintainedAsContingencyLossReserves" xlink:to="lab_mtg_PercentageOfPremiumsEarnedRequiredToBeMaintainedAsContingencyLossReserves" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DebtInstrumentNameDomain_693667c4-884e-4089-9ac9-ffd66e286fb3_terseLabel_en-US" xlink:label="lab_us-gaap_DebtInstrumentNameDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Debt Instrument, Name [Domain]</link:label>
    <link:label id="lab_us-gaap_DebtInstrumentNameDomain_label_en-US" xlink:label="lab_us-gaap_DebtInstrumentNameDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Debt Instrument, Name [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentNameDomain" xlink:to="lab_us-gaap_DebtInstrumentNameDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_AmountOfPolicyholdersPositionAboveOrBelowRequiredRegulatoryMinimum_47504944-72f8-4dae-acb1-29de9b2642df_verboseLabel_en-US" xlink:label="lab_mtg_AmountOfPolicyholdersPositionAboveOrBelowRequiredRegulatoryMinimum" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Amount of policyholders position above or below required MPP</link:label>
    <link:label id="lab_mtg_AmountOfPolicyholdersPositionAboveOrBelowRequiredRegulatoryMinimum_label_en-US" xlink:label="lab_mtg_AmountOfPolicyholdersPositionAboveOrBelowRequiredRegulatoryMinimum" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Amount of policyholders position above or below required regulatory minimum</link:label>
    <link:label id="lab_mtg_AmountOfPolicyholdersPositionAboveOrBelowRequiredRegulatoryMinimum_documentation_en-US" xlink:label="lab_mtg_AmountOfPolicyholdersPositionAboveOrBelowRequiredRegulatoryMinimum" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">The amount by which the entity's policyholders position (the insurer's net worth or surplus, contingency reserve and a portion of the reserves for unearned premiums) was above or below the required regulatory minimum of the entity's domiciliary state.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_AmountOfPolicyholdersPositionAboveOrBelowRequiredRegulatoryMinimum" xlink:href="mtg-20201231.xsd#mtg_AmountOfPolicyholdersPositionAboveOrBelowRequiredRegulatoryMinimum"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_AmountOfPolicyholdersPositionAboveOrBelowRequiredRegulatoryMinimum" xlink:to="lab_mtg_AmountOfPolicyholdersPositionAboveOrBelowRequiredRegulatoryMinimum" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_PremiumsWrittenGrossAbstract_20a51508-8682-4b43-ad33-4101fb6e3ae1_terseLabel_en-US" xlink:label="lab_us-gaap_PremiumsWrittenGrossAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Premiums written:</link:label>
    <link:label id="lab_us-gaap_PremiumsWrittenGrossAbstract_label_en-US" xlink:label="lab_us-gaap_PremiumsWrittenGrossAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Premiums Written, Gross [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PremiumsWrittenGrossAbstract" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PremiumsWrittenGrossAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PremiumsWrittenGrossAbstract" xlink:to="lab_us-gaap_PremiumsWrittenGrossAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CommonStockMember_d2cbbc41-f8da-49ed-a48d-f9e9ae758a13_terseLabel_en-US" xlink:label="lab_us-gaap_CommonStockMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Common stock</link:label>
    <link:label id="lab_us-gaap_CommonStockMember_label_en-US" xlink:label="lab_us-gaap_CommonStockMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Common Stock [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockMember" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CommonStockMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockMember" xlink:to="lab_us-gaap_CommonStockMember" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_StatutoryCapitalRequirementsRiskToCapitalRatio_3003796b-441b-433d-8bec-0888792d5c57_terseLabel_en-US" xlink:label="lab_mtg_StatutoryCapitalRequirementsRiskToCapitalRatio" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Risk to capital ratio</link:label>
    <link:label id="lab_mtg_StatutoryCapitalRequirementsRiskToCapitalRatio_label_en-US" xlink:label="lab_mtg_StatutoryCapitalRequirementsRiskToCapitalRatio" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Statutory Capital Requirements, Risk To Capital Ratio</link:label>
    <link:label id="lab_mtg_StatutoryCapitalRequirementsRiskToCapitalRatio_documentation_en-US" xlink:label="lab_mtg_StatutoryCapitalRequirementsRiskToCapitalRatio" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Statutory Capital Requirements, Risk To Capital Ratio</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_StatutoryCapitalRequirementsRiskToCapitalRatio" xlink:href="mtg-20201231.xsd#mtg_StatutoryCapitalRequirementsRiskToCapitalRatio"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_StatutoryCapitalRequirementsRiskToCapitalRatio" xlink:to="lab_mtg_StatutoryCapitalRequirementsRiskToCapitalRatio" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_Security12bTitle_5adf3a35-fb42-4ae5-b320-2968da71226e_terseLabel_en-US" xlink:label="lab_dei_Security12bTitle" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Title of 12(b) Security</link:label>
    <link:label id="lab_dei_Security12bTitle_label_en-US" xlink:label="lab_dei_Security12bTitle" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Title of 12(b) Security</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_Security12bTitle" xlink:href="https://xbrl.sec.gov/dei/2020/dei-2020-01-31.xsd#dei_Security12bTitle"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_Security12bTitle" xlink:to="lab_dei_Security12bTitle" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_01c7059f-5cfd-437a-ac73-e9531e623e7a_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award [Line Items]</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award [Line Items]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_LegalMattersAndContingenciesTextBlock_fd4ae03a-d5fa-40a5-9ba1-6190a0bf0e61_verboseLabel_en-US" xlink:label="lab_us-gaap_LegalMattersAndContingenciesTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Litigation and Contingencies</link:label>
    <link:label id="lab_us-gaap_LegalMattersAndContingenciesTextBlock_label_en-US" xlink:label="lab_us-gaap_LegalMattersAndContingenciesTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Legal Matters and Contingencies [Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LegalMattersAndContingenciesTextBlock" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LegalMattersAndContingenciesTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LegalMattersAndContingenciesTextBlock" xlink:to="lab_us-gaap_LegalMattersAndContingenciesTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DebtInstrumentRedemptionPeriodOneMember_d078d463-26bd-4f73-ac79-5bc767a8fd91_terseLabel_en-US" xlink:label="lab_us-gaap_DebtInstrumentRedemptionPeriodOneMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Debt Instrument, Redemption, Period One</link:label>
    <link:label id="lab_us-gaap_DebtInstrumentRedemptionPeriodOneMember_label_en-US" xlink:label="lab_us-gaap_DebtInstrumentRedemptionPeriodOneMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Debt Instrument, Redemption, Period One [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentRedemptionPeriodOneMember" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentRedemptionPeriodOneMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentRedemptionPeriodOneMember" xlink:to="lab_us-gaap_DebtInstrumentRedemptionPeriodOneMember" xlink:type="arc" order="1"/>
    <link:label id="lab_srt_CondensedFinancialStatementsCaptionsLineItems_6b07a119-17cd-4c61-bc39-3b120530a715_terseLabel_en-US" xlink:label="lab_srt_CondensedFinancialStatementsCaptionsLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Condensed Financial Statements, Captions [Line Items]</link:label>
    <link:label id="lab_srt_CondensedFinancialStatementsCaptionsLineItems_label_en-US" xlink:label="lab_srt_CondensedFinancialStatementsCaptionsLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Condensed Financial Statements, Captions [Line Items]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CondensedFinancialStatementsCaptionsLineItems" xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_CondensedFinancialStatementsCaptionsLineItems"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_CondensedFinancialStatementsCaptionsLineItems" xlink:to="lab_srt_CondensedFinancialStatementsCaptionsLineItems" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_PrimaryDefaultInventoryRollForward_31fe6fb8-f575-43d0-b2f3-a232c2f818c6_terseLabel_en-US" xlink:label="lab_mtg_PrimaryDefaultInventoryRollForward" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Primary Default Inventory [Roll Forward]</link:label>
    <link:label id="lab_mtg_PrimaryDefaultInventoryRollForward_label_en-US" xlink:label="lab_mtg_PrimaryDefaultInventoryRollForward" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Primary Default Inventory [Roll Forward]</link:label>
    <link:label id="lab_mtg_PrimaryDefaultInventoryRollForward_documentation_en-US" xlink:label="lab_mtg_PrimaryDefaultInventoryRollForward" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_PrimaryDefaultInventoryRollForward" xlink:href="mtg-20201231.xsd#mtg_PrimaryDefaultInventoryRollForward"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_PrimaryDefaultInventoryRollForward" xlink:to="lab_mtg_PrimaryDefaultInventoryRollForward" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfSharebasedCompensationRestrictedStockAndRestrictedStockUnitsActivityTableTextBlock_1099c5ce-a9ac-4c72-b291-9fb830c4ba37_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfSharebasedCompensationRestrictedStockAndRestrictedStockUnitsActivityTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Summary of restricted stock or restricted stock unit activity</link:label>
    <link:label id="lab_us-gaap_ScheduleOfSharebasedCompensationRestrictedStockAndRestrictedStockUnitsActivityTableTextBlock_label_en-US" xlink:label="lab_us-gaap_ScheduleOfSharebasedCompensationRestrictedStockAndRestrictedStockUnitsActivityTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Share-based Payment Arrangement, Restricted Stock and Restricted Stock Unit, Activity [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfSharebasedCompensationRestrictedStockAndRestrictedStockUnitsActivityTableTextBlock" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfSharebasedCompensationRestrictedStockAndRestrictedStockUnitsActivityTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfSharebasedCompensationRestrictedStockAndRestrictedStockUnitsActivityTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfSharebasedCompensationRestrictedStockAndRestrictedStockUnitsActivityTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_PaymentsToAcquireInvestments_218900e7-fab4-441c-ba8d-095985cd948b_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_PaymentsToAcquireInvestments" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Purchases of investments</link:label>
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    <link:label id="lab_mtg_NetdeferredtaxassetliabilityTableTextBlock_7a91a429-2018-441b-b5bf-2a388819111e_verboseLabel_en-US" xlink:label="lab_mtg_NetdeferredtaxassetliabilityTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Components of the net deferred tax asset (liability)</link:label>
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    <link:label id="lab_srt_MaximumMember_label_en-US" xlink:label="lab_srt_MaximumMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Maximum [Member]</link:label>
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    <link:label id="lab_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree_5a871a41-75c9-45c2-aa75-408b942ea1f3_terseLabel_en-US" xlink:label="lab_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">2023</link:label>
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    <link:label id="lab_us-gaap_AllOtherCorporateBondsMember_0b438926-2d25-4334-a804-5fb594c5f960_terseLabel_en-US" xlink:label="lab_us-gaap_AllOtherCorporateBondsMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">All other corporate bonds</link:label>
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    <link:label id="lab_mtg_PaymentOfOriginalIssueDiscountConvertibleJuniorSubordinatedDebentures_0533655f-8bb5-4ab4-8cfe-b4f2837d860c_negatedTerseLabel_en-US" xlink:label="lab_mtg_PaymentOfOriginalIssueDiscountConvertibleJuniorSubordinatedDebentures" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Payment of original issue discount- convertible junior subordinated debentures</link:label>
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    <link:loc xlink:type="locator" xlink:label="loc_mtg_PaymentOfOriginalIssueDiscountConvertibleJuniorSubordinatedDebentures" xlink:href="mtg-20201231.xsd#mtg_PaymentOfOriginalIssueDiscountConvertibleJuniorSubordinatedDebentures"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_PaymentOfOriginalIssueDiscountConvertibleJuniorSubordinatedDebentures" xlink:to="lab_mtg_PaymentOfOriginalIssueDiscountConvertibleJuniorSubordinatedDebentures" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DomesticCountryMember_fddc50e6-987d-4849-99e5-22b68cb049d6_terseLabel_en-US" xlink:label="lab_us-gaap_DomesticCountryMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">IRS</link:label>
    <link:label id="lab_us-gaap_DomesticCountryMember_label_en-US" xlink:label="lab_us-gaap_DomesticCountryMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Domestic Tax Authority [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DomesticCountryMember" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DomesticCountryMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DomesticCountryMember" xlink:to="lab_us-gaap_DomesticCountryMember" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_DocumentsIncorporatedByReferenceTextBlock_de42d242-9d89-444c-b5d1-37729a5d9e6e_terseLabel_en-US" xlink:label="lab_dei_DocumentsIncorporatedByReferenceTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Documents Incorporated by Reference</link:label>
    <link:label id="lab_dei_DocumentsIncorporatedByReferenceTextBlock_label_en-US" xlink:label="lab_dei_DocumentsIncorporatedByReferenceTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Documents Incorporated by Reference [Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentsIncorporatedByReferenceTextBlock" xlink:href="https://xbrl.sec.gov/dei/2020/dei-2020-01-31.xsd#dei_DocumentsIncorporatedByReferenceTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_DocumentsIncorporatedByReferenceTextBlock" xlink:to="lab_dei_DocumentsIncorporatedByReferenceTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost_36c14055-9246-4898-a7b0-b17eac659c49_verboseLabel_en-US" xlink:label="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Due in one year or less</link:label>
    <link:label id="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost_label_en-US" xlink:label="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Amortized Cost</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost"/>
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    <link:label id="lab_mtg_CreditUnionQuotaShareReinsuranceAgreementMember_ac5a978c-28fe-4971-a782-6ac801dd8440_terseLabel_en-US" xlink:label="lab_mtg_CreditUnionQuotaShareReinsuranceAgreementMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Credit Union QSR</link:label>
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    <link:loc xlink:type="locator" xlink:label="loc_mtg_CreditUnionQuotaShareReinsuranceAgreementMember" xlink:href="mtg-20201231.xsd#mtg_CreditUnionQuotaShareReinsuranceAgreementMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_CreditUnionQuotaShareReinsuranceAgreementMember" xlink:to="lab_mtg_CreditUnionQuotaShareReinsuranceAgreementMember" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_LegalEntityAxis_e7f65f82-080f-4bec-ade6-a2a068fcaecd_terseLabel_en-US" xlink:label="lab_dei_LegalEntityAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Legal Entity [Axis]</link:label>
    <link:label id="lab_dei_LegalEntityAxis_label_en-US" xlink:label="lab_dei_LegalEntityAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Legal Entity [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LegalEntityAxis" xlink:href="https://xbrl.sec.gov/dei/2020/dei-2020-01-31.xsd#dei_LegalEntityAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_LegalEntityAxis" xlink:to="lab_dei_LegalEntityAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_CityAreaCode_2c3f8bbc-c146-41aa-852e-be63b8c4462f_terseLabel_en-US" xlink:label="lab_dei_CityAreaCode" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">City Area Code</link:label>
    <link:label id="lab_dei_CityAreaCode_label_en-US" xlink:label="lab_dei_CityAreaCode" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">City Area Code</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_CityAreaCode" xlink:href="https://xbrl.sec.gov/dei/2020/dei-2020-01-31.xsd#dei_CityAreaCode"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_CityAreaCode" xlink:to="lab_dei_CityAreaCode" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_QuarterlyFinancialInformationTextBlock_16d06275-24b8-4769-aab6-eea49fc054b7_terseLabel_en-US" xlink:label="lab_us-gaap_QuarterlyFinancialInformationTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Unaudited Quarterly Financial Data</link:label>
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    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_QuarterlyFinancialInformationTextBlock" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_QuarterlyFinancialInformationTextBlock"/>
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    <link:label id="lab_mtg_DefinedBenefitPlanFutureEarningsPeriodUsedInDeterminingExpectedAverageRateOfEarnings_05eff754-fe5b-40d6-902c-dd7f8e22c33e_verboseLabel_en-US" xlink:label="lab_mtg_DefinedBenefitPlanFutureEarningsPeriodUsedInDeterminingExpectedAverageRateOfEarnings" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Future earnings period used in determining the expected average rate of earnings</link:label>
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    <link:label id="lab_us-gaap_EarlyRepaymentOfSeniorDebt_3e7ce636-ef5e-45fc-96a6-f58f84846771_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_EarlyRepaymentOfSeniorDebt" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Purchase of senior notes</link:label>
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    <link:label id="lab_us-gaap_DebtDisclosureAbstract_640118f6-f60f-4acb-8824-18e419a897b0_terseLabel_en-US" xlink:label="lab_us-gaap_DebtDisclosureAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Debt Disclosure [Abstract]</link:label>
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    <link:label id="lab_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_215e3d53-1038-41c8-beaf-796ec725dd55_terseLabel_en-US" xlink:label="lab_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Accumulated Other Comprehensive Income (Loss) [Line Items]</link:label>
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    <link:label id="lab_us-gaap_ComprehensiveIncomeNoteTextBlock_11d95d44-118b-4774-b58c-ebd92298b17e_verboseLabel_en-US" xlink:label="lab_us-gaap_ComprehensiveIncomeNoteTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Other Comprehensive Income (Loss)</link:label>
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    <link:label id="lab_mtg_ConvertibleJuniorDebenturesat9perannumDue2063Member_ffd538ea-d49e-4bd7-b5bc-849aa85a42ff_verboseLabel_en-US" xlink:label="lab_mtg_ConvertibleJuniorDebenturesat9perannumDue2063Member" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">9% Convertible Junior Subordinated Debentures due 2063</link:label>
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    <link:label id="lab_us-gaap_StatementOfFinancialPositionAbstract_171d7dd7-8a04-4b1f-a261-6fd93322ecc2_terseLabel_en-US" xlink:label="lab_us-gaap_StatementOfFinancialPositionAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">CONDENSED BALANCE SHEETS</link:label>
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    <link:label id="lab_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansTaxPortionAttributableToParent_7025823d-fb10-4c97-a6ad-bef4e6e76cd0_terseLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansTaxPortionAttributableToParent" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Income tax (expense) benefit</link:label>
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    <link:label id="lab_mtg_Risktocapitalratioatendofperiod_bb62f03c-3fc2-457c-a3c9-1afe6c8fa0f0_terseLabel_en-US" xlink:label="lab_mtg_Risktocapitalratioatendofperiod" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Risk to capital ratio at end of period</link:label>
    <link:label id="lab_mtg_Risktocapitalratioatendofperiod_label_en-US" xlink:label="lab_mtg_Risktocapitalratioatendofperiod" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Risk to capital ratio at end of period</link:label>
    <link:label id="lab_mtg_Risktocapitalratioatendofperiod_documentation_en-US" xlink:label="lab_mtg_Risktocapitalratioatendofperiod" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">The entity's risk-to-capital ratio as of the end of the reporting period.</link:label>
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    <link:label id="lab_us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent_780cd4fb-64a8-4de1-8dae-a79e1a40c037_terseLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Change in unrealized investment gains and losses</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent_1b0105e9-f2a7-408a-92da-7c1a308201b0_totalLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Net of taxes</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent_label_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax, Portion Attributable to Parent</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent"/>
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    <link:label id="lab_us-gaap_PremiumsEarnedNetPropertyAndCasualty_f3993c62-13d2-4af2-823e-dec6337e88d6_totalLabel_en-US" xlink:label="lab_us-gaap_PremiumsEarnedNetPropertyAndCasualty" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Net premiums earned</link:label>
    <link:label id="lab_us-gaap_PremiumsEarnedNetPropertyAndCasualty_982f1cd3-0bfa-4dfa-aaf1-37fafd1cac3f_terseLabel_en-US" xlink:label="lab_us-gaap_PremiumsEarnedNetPropertyAndCasualty" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Net premiums earned</link:label>
    <link:label id="lab_us-gaap_PremiumsEarnedNetPropertyAndCasualty_label_en-US" xlink:label="lab_us-gaap_PremiumsEarnedNetPropertyAndCasualty" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Premiums Earned, Net, Property and Casualty</link:label>
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    <link:label id="lab_us-gaap_ValuationAllowanceLineItems_86c58071-9efe-4d75-8817-4370126b3487_terseLabel_en-US" xlink:label="lab_us-gaap_ValuationAllowanceLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Valuation Allowance [Line Items]</link:label>
    <link:label id="lab_us-gaap_ValuationAllowanceLineItems_label_en-US" xlink:label="lab_us-gaap_ValuationAllowanceLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Valuation Allowance [Line Items]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationAllowanceLineItems" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ValuationAllowanceLineItems"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ValuationAllowanceLineItems" xlink:to="lab_us-gaap_ValuationAllowanceLineItems" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_RealizedStatutoryLossFromAffiliate_2d6733cc-e213-4dc7-bd9c-9ff5071e48ea_terseLabel_en-US" xlink:label="lab_mtg_RealizedStatutoryLossFromAffiliate" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Realized statutory loss on merger of affiliate, eliminated in consolidation</link:label>
    <link:label id="lab_mtg_RealizedStatutoryLossFromAffiliate_label_en-US" xlink:label="lab_mtg_RealizedStatutoryLossFromAffiliate" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Realized statutory loss from affiliate</link:label>
    <link:label id="lab_mtg_RealizedStatutoryLossFromAffiliate_documentation_en-US" xlink:label="lab_mtg_RealizedStatutoryLossFromAffiliate" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Realized statutory loss from affiliate due to recognition of cumulative unrealized losses on merger/disposition of affiliate.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_RealizedStatutoryLossFromAffiliate" xlink:href="mtg-20201231.xsd#mtg_RealizedStatutoryLossFromAffiliate"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_RealizedStatutoryLossFromAffiliate" xlink:to="lab_mtg_RealizedStatutoryLossFromAffiliate" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract_af04d73c-ed43-4d5e-bd98-638f38773573_terseLabel_en-US" xlink:label="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Maturities, Fair Value [Abstract]</link:label>
    <link:label id="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract_label_en-US" xlink:label="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Debt Securities, Available-for-sale, Fair Value, Fiscal Year Maturity [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract" xlink:to="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_43220b5e-e77d-436f-8f97-388d04f9ad90_negatedLabel_en-US" xlink:label="lab_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Additions to property and equipment</link:label>
    <link:label id="lab_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_label_en-US" xlink:label="lab_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Payments to Acquire Property, Plant, and Equipment</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PaymentsToAcquirePropertyPlantAndEquipment"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" xlink:to="lab_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ConvertibleSubordinatedDebt_cc587cb8-b6a4-4246-8ed3-0ccf918f210d_terseLabel_en-US" xlink:label="lab_us-gaap_ConvertibleSubordinatedDebt" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Convertible junior subordinated debentures</link:label>
    <link:label id="lab_us-gaap_ConvertibleSubordinatedDebt_7dd8f21e-faa1-4355-b2c8-40eaf992427c_verboseLabel_en-US" xlink:label="lab_us-gaap_ConvertibleSubordinatedDebt" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Convertible junior subordinated debentures</link:label>
    <link:label id="lab_us-gaap_ConvertibleSubordinatedDebt_label_en-US" xlink:label="lab_us-gaap_ConvertibleSubordinatedDebt" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Convertible Subordinated Debt</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConvertibleSubordinatedDebt" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ConvertibleSubordinatedDebt"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ConvertibleSubordinatedDebt" xlink:to="lab_us-gaap_ConvertibleSubordinatedDebt" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ProceedsFromIssuanceOfLongTermDebt_2e430664-5a09-4bc1-b01e-06d933bc01b7_terseLabel_en-US" xlink:label="lab_us-gaap_ProceedsFromIssuanceOfLongTermDebt" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Proceeds from issuance of senior notes</link:label>
    <link:label id="lab_us-gaap_ProceedsFromIssuanceOfLongTermDebt_label_en-US" xlink:label="lab_us-gaap_ProceedsFromIssuanceOfLongTermDebt" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Proceeds from Issuance of Long-term Debt</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfLongTermDebt" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ProceedsFromIssuanceOfLongTermDebt"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromIssuanceOfLongTermDebt" xlink:to="lab_us-gaap_ProceedsFromIssuanceOfLongTermDebt" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountAssumed_a5b9a86f-21fb-4d32-8744-4bd34a8d118d_terseLabel_en-US" xlink:label="lab_us-gaap_ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountAssumed" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Losses incurred, assumed</link:label>
    <link:label id="lab_us-gaap_ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountAssumed_label_en-US" xlink:label="lab_us-gaap_ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountAssumed" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Policyholder Benefits and Claims Incurred, Assumed</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountAssumed" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountAssumed"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountAssumed" xlink:to="lab_us-gaap_ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountAssumed" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ConvertibleSubordinatedDebtMember_7513c926-b5e1-41dd-a770-24e55962e436_terseLabel_en-US" xlink:label="lab_us-gaap_ConvertibleSubordinatedDebtMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Convertible Junior Subordinated Debentures, at 9% per annum, Due 2063</link:label>
    <link:label id="lab_us-gaap_ConvertibleSubordinatedDebtMember_label_en-US" xlink:label="lab_us-gaap_ConvertibleSubordinatedDebtMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Convertible Subordinated Debt [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConvertibleSubordinatedDebtMember" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ConvertibleSubordinatedDebtMember"/>
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    <link:label id="lab_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFive_9ea41640-1a5a-42aa-b2a2-56e154b49b90_terseLabel_en-US" xlink:label="lab_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFive" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">2025 and thereafter</link:label>
    <link:label id="lab_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFive_label_en-US" xlink:label="lab_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFive" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Lessee, Operating Lease, Liability, Payments, Due Year Five</link:label>
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    <link:label id="lab_us-gaap_DueFromRelatedParties_21aabdd6-0085-4911-a793-a8fbd16457d5_terseLabel_en-US" xlink:label="lab_us-gaap_DueFromRelatedParties" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Accounts receivable - affiliates</link:label>
    <link:label id="lab_us-gaap_DueFromRelatedParties_label_en-US" xlink:label="lab_us-gaap_DueFromRelatedParties" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Due from Related Parties</link:label>
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    <link:label id="lab_mtg_PeriodInWhichReasonableCommercialEffortsMustBeginMaximum_74c8d956-e58f-43be-8875-e837bcb94f43_verboseLabel_en-US" xlink:label="lab_mtg_PeriodInWhichReasonableCommercialEffortsMustBeginMaximum" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Period in which reasonable commercial efforts must begin, maximum</link:label>
    <link:label id="lab_mtg_PeriodInWhichReasonableCommercialEffortsMustBeginMaximum_label_en-US" xlink:label="lab_mtg_PeriodInWhichReasonableCommercialEffortsMustBeginMaximum" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Period in which reasonable commercial efforts must begin maximum</link:label>
    <link:label id="lab_mtg_PeriodInWhichReasonableCommercialEffortsMustBeginMaximum_documentation_en-US" xlink:label="lab_mtg_PeriodInWhichReasonableCommercialEffortsMustBeginMaximum" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">The maximum period, in business days, after payment of interest on debentures that was not deferred, in which the entity must begin reasonable commercial efforts to sell qualifying securities to unaffiliated persons pursuant to the optional deferral provision under the note agreement(s).</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_PeriodInWhichReasonableCommercialEffortsMustBeginMaximum" xlink:href="mtg-20201231.xsd#mtg_PeriodInWhichReasonableCommercialEffortsMustBeginMaximum"/>
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    <link:label id="lab_us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsAlternativeMinimumTax_d7bbbe3b-da70-48c7-a23d-34900169a68a_terseLabel_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsAlternativeMinimumTax" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">AMT credit carryforward</link:label>
    <link:label id="lab_us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsAlternativeMinimumTax_label_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsAlternativeMinimumTax" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Deferred Tax Assets, Tax Credit Carryforwards, Alternative Minimum Tax</link:label>
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    <link:label id="lab_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeBeforeTax_88fe5b4d-3a71-4863-9c29-71bcba40a4f8_totalLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeBeforeTax" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Total at Year End</link:label>
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    <link:label id="lab_mtg_TaxAndLossBondsHeld_656f3407-d972-42e7-8bdf-6f8d32605651_terseLabel_en-US" xlink:label="lab_mtg_TaxAndLossBondsHeld" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Amount of tax and loss bonds held</link:label>
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    <link:label id="lab_mtg_TaxAndLossBondsHeld_documentation_en-US" xlink:label="lab_mtg_TaxAndLossBondsHeld" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Amount of tax and loss bonds held by the reporting entity.</link:label>
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    <link:label id="lab_us-gaap_InvestmentsClassifiedByContractualMaturityDateTableTextBlock_d7b07b6d-d88f-40d1-9c1d-6028cde9a849_terseLabel_en-US" xlink:label="lab_us-gaap_InvestmentsClassifiedByContractualMaturityDateTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Amortized cost and fair values of debt securities by contractual maturity</link:label>
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    <link:label id="lab_mtg_MaximumPeriodForWhichInterestPaymentsMayBeDeferredWithoutGivingRiseToEventOfDefault_8cc09e41-017a-42ac-8ec8-d07545da7b02_verboseLabel_en-US" xlink:label="lab_mtg_MaximumPeriodForWhichInterestPaymentsMayBeDeferredWithoutGivingRiseToEventOfDefault" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Maximum period for which interest payments may be deferred without giving rise to an event of default</link:label>
    <link:label id="lab_mtg_MaximumPeriodForWhichInterestPaymentsMayBeDeferredWithoutGivingRiseToEventOfDefault_label_en-US" xlink:label="lab_mtg_MaximumPeriodForWhichInterestPaymentsMayBeDeferredWithoutGivingRiseToEventOfDefault" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Maximum period for which interest payments may be deferred without giving rise to an event of default</link:label>
    <link:label id="lab_mtg_MaximumPeriodForWhichInterestPaymentsMayBeDeferredWithoutGivingRiseToEventOfDefault_documentation_en-US" xlink:label="lab_mtg_MaximumPeriodForWhichInterestPaymentsMayBeDeferredWithoutGivingRiseToEventOfDefault" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">The maximum length of time for which interest payments on the convertible debentures may be deferred without giving rise to an event of default.</link:label>
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    <link:label id="lab_mtg_NumberOfJurisdictionsWithRiskToCapitalRequirements_8bd19003-db4b-4436-b590-1f6c68bfab41_verboseLabel_en-US" xlink:label="lab_mtg_NumberOfJurisdictionsWithRiskToCapitalRequirements" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Number of jurisdictions with risk-to-capital requirements</link:label>
    <link:label id="lab_mtg_NumberOfJurisdictionsWithRiskToCapitalRequirements_label_en-US" xlink:label="lab_mtg_NumberOfJurisdictionsWithRiskToCapitalRequirements" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Number of jurisdictions with risk to capital requirements</link:label>
    <link:label id="lab_mtg_NumberOfJurisdictionsWithRiskToCapitalRequirements_documentation_en-US" xlink:label="lab_mtg_NumberOfJurisdictionsWithRiskToCapitalRequirements" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">The number of jurisdictions that require a mortgage insurer to maintain a minimum amount of statutory capital relative to the risk in force (or a similar measure) in order for the mortgage insurer to continue to write new business. This is generally referred to as a risk-to-capital requirement.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_NumberOfJurisdictionsWithRiskToCapitalRequirements" xlink:href="mtg-20201231.xsd#mtg_NumberOfJurisdictionsWithRiskToCapitalRequirements"/>
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    <link:label id="lab_us-gaap_EarlyRepaymentOfSubordinatedDebt_2e08bad6-4672-4bcf-92a4-91eb228cd6d5_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_EarlyRepaymentOfSubordinatedDebt" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Purchase of convertible junior subordinated debentures</link:label>
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    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarlyRepaymentOfSubordinatedDebt" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EarlyRepaymentOfSubordinatedDebt"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EarlyRepaymentOfSubordinatedDebt" xlink:to="lab_us-gaap_EarlyRepaymentOfSubordinatedDebt" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_PremiumsPercentageAssumedToNet_0877af83-8ed4-45b3-a177-60361c7bec76_terseLabel_en-US" xlink:label="lab_us-gaap_PremiumsPercentageAssumedToNet" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Percentage of Amount Assumed to Net</link:label>
    <link:label id="lab_us-gaap_PremiumsPercentageAssumedToNet_label_en-US" xlink:label="lab_us-gaap_PremiumsPercentageAssumedToNet" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">SEC Schedule, 12-17, Insurance Companies, Reinsurance, Premium, Percentage Assumed to Net</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PremiumsPercentageAssumedToNet" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PremiumsPercentageAssumedToNet"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PremiumsPercentageAssumedToNet" xlink:to="lab_us-gaap_PremiumsPercentageAssumedToNet" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_LiabilityForClaimsAndClaimsAdjustmentExpensePropertyCasualtyLiability_6d123aa4-56ce-4967-8f27-f0949048a943_terseLabel_en-US" xlink:label="lab_us-gaap_LiabilityForClaimsAndClaimsAdjustmentExpensePropertyCasualtyLiability" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Loss reserves</link:label>
    <link:label id="lab_us-gaap_LiabilityForClaimsAndClaimsAdjustmentExpensePropertyCasualtyLiability_label_en-US" xlink:label="lab_us-gaap_LiabilityForClaimsAndClaimsAdjustmentExpensePropertyCasualtyLiability" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Liability for Claims and Claims Adjustment Expense, Property Casualty Liability</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForClaimsAndClaimsAdjustmentExpensePropertyCasualtyLiability" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LiabilityForClaimsAndClaimsAdjustmentExpensePropertyCasualtyLiability"/>
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    <link:label id="lab_dei_CurrentFiscalYearEndDate_0142ad4c-9c68-4ba8-abf8-451da994dfe5_terseLabel_en-US" xlink:label="lab_dei_CurrentFiscalYearEndDate" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Current Fiscal Year End Date</link:label>
    <link:label id="lab_dei_CurrentFiscalYearEndDate_label_en-US" xlink:label="lab_dei_CurrentFiscalYearEndDate" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Current Fiscal Year End Date</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_CurrentFiscalYearEndDate" xlink:href="https://xbrl.sec.gov/dei/2020/dei-2020-01-31.xsd#dei_CurrentFiscalYearEndDate"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_CurrentFiscalYearEndDate" xlink:to="lab_dei_CurrentFiscalYearEndDate" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive_04660f2a-09b8-40c7-b7d9-60288232e088_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Expected Benefit Payments for the Year Ending: Current plus 5</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Defined Benefit Plan, Expected Future Benefit Payment, Year Five</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive" xlink:to="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems_7adb9291-d957-48e0-85ff-8e55d140a35a_terseLabel_en-US" xlink:label="lab_us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]</link:label>
    <link:label id="lab_us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems_label_en-US" xlink:label="lab_us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems" xlink:to="lab_us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedContributionPlanEmployerMatchingContributionPercentOfMatch_3331c108-eb51-45fa-884e-f223eeefef12_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedContributionPlanEmployerMatchingContributionPercentOfMatch" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Matching contribution rate on employees' contributions (in hundredths)</link:label>
    <link:label id="lab_us-gaap_DefinedContributionPlanEmployerMatchingContributionPercentOfMatch_label_en-US" xlink:label="lab_us-gaap_DefinedContributionPlanEmployerMatchingContributionPercentOfMatch" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Defined Contribution Plan, Employer Matching Contribution, Percent of Match</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedContributionPlanEmployerMatchingContributionPercentOfMatch" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DefinedContributionPlanEmployerMatchingContributionPercentOfMatch"/>
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    <link:label id="lab_mtg_HomeRespecialpurposeinsurersMember_493234de-95d3-4b27-998c-8fe6493509c7_terseLabel_en-US" xlink:label="lab_mtg_HomeRespecialpurposeinsurersMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Home Re special purpose insurers</link:label>
    <link:label id="lab_mtg_HomeRespecialpurposeinsurersMember_label_en-US" xlink:label="lab_mtg_HomeRespecialpurposeinsurersMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Home Re special purpose insurers [Member]</link:label>
    <link:label id="lab_mtg_HomeRespecialpurposeinsurersMember_documentation_en-US" xlink:label="lab_mtg_HomeRespecialpurposeinsurersMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Home Re special purpose insurers [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_HomeRespecialpurposeinsurersMember" xlink:href="mtg-20201231.xsd#mtg_HomeRespecialpurposeinsurersMember"/>
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    <link:label id="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_31789abb-1d76-41a7-9d59-d120459123af_terseLabel_en-US" xlink:label="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]</link:label>
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    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems"/>
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    <link:label id="lab_us-gaap_DebtInstrumentFairValue_f44acb9f-a361-4784-aa37-bff4510adc9b_totalLabel_en-US" xlink:label="lab_us-gaap_DebtInstrumentFairValue" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Total financial liabilities</link:label>
    <link:label id="lab_us-gaap_DebtInstrumentFairValue_label_en-US" xlink:label="lab_us-gaap_DebtInstrumentFairValue" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Debt Instrument, Fair Value Disclosure</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentFairValue" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentFairValue"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentFairValue" xlink:to="lab_us-gaap_DebtInstrumentFairValue" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_93077fe3-9ded-41ad-90ec-78ded3608558_periodStartLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Restricted stock outstanding at end of period (in dollars per share)</link:label>
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    <link:label id="lab_us-gaap_EarningsPerShareTextBlock_05035611-a4b0-4604-9636-f838ca4beca3_verboseLabel_en-US" xlink:label="lab_us-gaap_EarningsPerShareTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Earnings per Share</link:label>
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    <link:label id="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract_75cc2d6f-9f8b-4b53-9653-d545fc6d4dd4_terseLabel_en-US" xlink:label="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Maturities, Amortized Cost [Abstract]</link:label>
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    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract"/>
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    <link:label id="lab_us-gaap_ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountCeded_aae8b5a8-c6ef-405d-a82e-d1e91bae0195_negatedLabel_en-US" xlink:label="lab_us-gaap_ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountCeded" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Losses incurred, ceded</link:label>
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    <link:label id="lab_mtg_AmountOfRequiredMpp_label_en-US" xlink:label="lab_mtg_AmountOfRequiredMpp" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Amount of required MPP</link:label>
    <link:label id="lab_mtg_AmountOfRequiredMpp_documentation_en-US" xlink:label="lab_mtg_AmountOfRequiredMpp" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">The amount of minimum policyholder position (MPP) required by the entity's domiciliary state.</link:label>
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    <link:label id="lab_mtg_MortgageGuarantyInsuranceCorporationMember_737fbe04-2cb7-404f-92cb-7dd60d724101_terseLabel_en-US" xlink:label="lab_mtg_MortgageGuarantyInsuranceCorporationMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Mortgage Guaranty Insurance Corporation</link:label>
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    <link:label id="lab_mtg_MortgageGuarantyInsuranceCorporationMember_documentation_en-US" xlink:label="lab_mtg_MortgageGuarantyInsuranceCorporationMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Another company which is controlled, directly or indirectly, by its parent. The usual condition for control is ownership of a majority (over 50%) of the outstanding voting stock. The power to control may also exist with a lesser percentage of ownership, for example, by contract, lease, agreement with other stockholders or by court decree.</link:label>
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    <link:label id="lab_us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_ae5f05aa-b760-4db7-97c6-6c9ddb822318_terseLabel_en-US" xlink:label="lab_us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Dilutive securities - Share based compensation (in shares)</link:label>
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    <link:label id="lab_dei_EntityWellKnownSeasonedIssuer_9726f09e-87c7-4710-bf5b-9cd98593eab5_terseLabel_en-US" xlink:label="lab_dei_EntityWellKnownSeasonedIssuer" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Entity Well-known Seasoned Issuer</link:label>
    <link:label id="lab_dei_EntityWellKnownSeasonedIssuer_label_en-US" xlink:label="lab_dei_EntityWellKnownSeasonedIssuer" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Entity Well-known Seasoned Issuer</link:label>
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    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityWellKnownSeasonedIssuer" xlink:to="lab_dei_EntityWellKnownSeasonedIssuer" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_InvestmentsAbstract_edde885b-267a-4b3f-bcd8-4470f579bd5d_verboseLabel_en-US" xlink:label="lab_us-gaap_InvestmentsAbstract" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Investment portfolio:</link:label>
    <link:label id="lab_us-gaap_InvestmentsAbstract_f1583621-6633-475f-94e2-61566d03148d_terseLabel_en-US" xlink:label="lab_us-gaap_InvestmentsAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Investments [Abstract]</link:label>
    <link:label id="lab_us-gaap_InvestmentsAbstract_label_en-US" xlink:label="lab_us-gaap_InvestmentsAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Investments [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentsAbstract" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_InvestmentsAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InvestmentsAbstract" xlink:to="lab_us-gaap_InvestmentsAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfGainLossOnInvestmentsIncludingMarketableSecuritiesAndInvestmentsHeldAtCostIncomeStatementReportedAmountsSummaryLineItems_dd1f2401-d91d-4bff-be4f-62a11fac08a5_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfGainLossOnInvestmentsIncludingMarketableSecuritiesAndInvestmentsHeldAtCostIncomeStatementReportedAmountsSummaryLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Gain (Loss) on Securities [Line Items]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfGainLossOnInvestmentsIncludingMarketableSecuritiesAndInvestmentsHeldAtCostIncomeStatementReportedAmountsSummaryLineItems_label_en-US" xlink:label="lab_us-gaap_ScheduleOfGainLossOnInvestmentsIncludingMarketableSecuritiesAndInvestmentsHeldAtCostIncomeStatementReportedAmountsSummaryLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Gain (Loss) on Securities [Line Items]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfGainLossOnInvestmentsIncludingMarketableSecuritiesAndInvestmentsHeldAtCostIncomeStatementReportedAmountsSummaryLineItems" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfGainLossOnInvestmentsIncludingMarketableSecuritiesAndInvestmentsHeldAtCostIncomeStatementReportedAmountsSummaryLineItems"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfGainLossOnInvestmentsIncludingMarketableSecuritiesAndInvestmentsHeldAtCostIncomeStatementReportedAmountsSummaryLineItems" xlink:to="lab_us-gaap_ScheduleOfGainLossOnInvestmentsIncludingMarketableSecuritiesAndInvestmentsHeldAtCostIncomeStatementReportedAmountsSummaryLineItems" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_cfd2aab6-1afe-4e4f-ab73-cad3b0588a2c_terseLabel_en-US" xlink:label="lab_us-gaap_AOCIAttributableToParentNetOfTaxRollForward" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">AOCI Attributable to Parent, Net of Tax [Roll Forward]</link:label>
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    <link:label id="lab_us-gaap_DefinedBenefitPlanFundedStatusOfPlan_abef116f-0f50-40b3-b03f-83a1ae88d3b1_totalLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanFundedStatusOfPlan" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Funded Status - Overfunded/(Underfunded)</link:label>
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    <link:label id="lab_mtg_FivePointTwoFivePercentSeniorNotesMember_972b7f89-88a2-4b7b-bc48-a555f406491f_terseLabel_en-US" xlink:label="lab_mtg_FivePointTwoFivePercentSeniorNotesMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">5.25% Senior Notes due 2028</link:label>
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    <link:label id="lab_us-gaap_StockholdersEquity_e0af948e-0ea3-4f1f-aa17-ba4fda95e447_totalLabel_en-US" xlink:label="lab_us-gaap_StockholdersEquity" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Total shareholders' equity</link:label>
    <link:label id="lab_us-gaap_StockholdersEquity_cb4c88be-cd7b-4760-ad43-2923a1f2bd59_periodStartLabel_en-US" xlink:label="lab_us-gaap_StockholdersEquity" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Balance, beginning of year</link:label>
    <link:label id="lab_us-gaap_StockholdersEquity_fc72ecf2-f609-41c8-b8a1-c36041bf1318_periodEndLabel_en-US" xlink:label="lab_us-gaap_StockholdersEquity" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Balance, end of year</link:label>
    <link:label id="lab_us-gaap_StockholdersEquity_label_en-US" xlink:label="lab_us-gaap_StockholdersEquity" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Stockholders' Equity Attributable to Parent</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StockholdersEquity"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockholdersEquity" xlink:to="lab_us-gaap_StockholdersEquity" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_InformationByCategoryOfDebtSecurityAxis_bc0f3c7b-d903-4dc0-8ffc-b9241c2a4969_terseLabel_en-US" xlink:label="lab_us-gaap_InformationByCategoryOfDebtSecurityAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Gain (Loss) on Investments by Category [Axis]</link:label>
    <link:label id="lab_us-gaap_InformationByCategoryOfDebtSecurityAxis_label_en-US" xlink:label="lab_us-gaap_InformationByCategoryOfDebtSecurityAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Debt Security Category [Axis]</link:label>
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    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InformationByCategoryOfDebtSecurityAxis" xlink:to="lab_us-gaap_InformationByCategoryOfDebtSecurityAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_LocalPhoneNumber_5923fc3e-3709-48f7-a011-0d5943115f15_terseLabel_en-US" xlink:label="lab_dei_LocalPhoneNumber" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Local Phone Number</link:label>
    <link:label id="lab_dei_LocalPhoneNumber_label_en-US" xlink:label="lab_dei_LocalPhoneNumber" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Local Phone Number</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LocalPhoneNumber" xlink:href="https://xbrl.sec.gov/dei/2020/dei-2020-01-31.xsd#dei_LocalPhoneNumber"/>
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    <link:label id="lab_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_0915f1c9-4bd5-4c3d-85f7-de6fd3b2d58b_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Schedule of Related Party Transactions, by Related Party [Table]</link:label>
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    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable" xlink:to="lab_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FairValueDisclosuresTextBlock_cdb4c998-be27-4424-bbfa-f9de574da3f4_terseLabel_en-US" xlink:label="lab_us-gaap_FairValueDisclosuresTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Fair Value Measurements</link:label>
    <link:label id="lab_us-gaap_FairValueDisclosuresTextBlock_label_en-US" xlink:label="lab_us-gaap_FairValueDisclosuresTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Fair Value Disclosures [Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueDisclosuresTextBlock" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_FairValueDisclosuresTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueDisclosuresTextBlock" xlink:to="lab_us-gaap_FairValueDisclosuresTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DeferredPolicyAcquisitionCostAmortizationExpense_e760fa28-fbd3-44f7-97c3-108a29cb6a3d_terseLabel_en-US" xlink:label="lab_us-gaap_DeferredPolicyAcquisitionCostAmortizationExpense" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Amortization of deferred policy acquisition costs</link:label>
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    <link:label id="lab_mtg_InvestmentInHoldingCompanyDebt_eb7b1a8d-e83f-4474-8f57-bedd8dc5a6b1_terseLabel_en-US" xlink:label="lab_mtg_InvestmentInHoldingCompanyDebt" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Investment in holding company debt</link:label>
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    <link:label id="lab_mtg_InvestmentInHoldingCompanyDebt_documentation_en-US" xlink:label="lab_mtg_InvestmentInHoldingCompanyDebt" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">The investment in holding company debt at the end of the period.</link:label>
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    <link:label id="lab_mtg_StatutoryAccountingPracticesTextBlock_21e731f9-4bb1-4986-aa83-af222437a557_verboseLabel_en-US" xlink:label="lab_mtg_StatutoryAccountingPracticesTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Statutory Information</link:label>
    <link:label id="lab_mtg_StatutoryAccountingPracticesTextBlock_label_en-US" xlink:label="lab_mtg_StatutoryAccountingPracticesTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Statutory Accounting Practices [Text Block]</link:label>
    <link:label id="lab_mtg_StatutoryAccountingPracticesTextBlock_documentation_en-US" xlink:label="lab_mtg_StatutoryAccountingPracticesTextBlock" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">The entire disclosure of how the entity's reporting under GAAP as of the balance sheet date differs from the results based on prescribed and permitted accounting practices of the state or country of domicile in which a relevant statutory filing is made.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_StatutoryAccountingPracticesTextBlock" xlink:href="mtg-20201231.xsd#mtg_StatutoryAccountingPracticesTextBlock"/>
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    <link:label id="lab_mtg_ReinsuranceQuotaShareReinsuranceAgreementTermsThresholdForPrivateMortgageInsurerEligibilityRequirementsForTerminationElection_e655f90d-c8d5-4f0e-9121-f0000d374b17_terseLabel_en-US" xlink:label="lab_mtg_ReinsuranceQuotaShareReinsuranceAgreementTermsThresholdForPrivateMortgageInsurerEligibilityRequirementsForTerminationElection" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Threshold for private mortgage insurer eligibility requirements for termination election</link:label>
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    <link:label id="lab_us-gaap_ValuationAllowanceTable_aeb598d2-87a5-4008-837d-66a3f38884a0_terseLabel_en-US" xlink:label="lab_us-gaap_ValuationAllowanceTable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Valuation Allowance [Table]</link:label>
    <link:label id="lab_us-gaap_ValuationAllowanceTable_label_en-US" xlink:label="lab_us-gaap_ValuationAllowanceTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Valuation Allowance [Table]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationAllowanceTable" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ValuationAllowanceTable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ValuationAllowanceTable" xlink:to="lab_us-gaap_ValuationAllowanceTable" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_LossesIncurredAbstract_06efb8ac-760f-4360-9818-f5f3783cbd3b_terseLabel_en-US" xlink:label="lab_mtg_LossesIncurredAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Losses incurred: [Abstract]</link:label>
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    <link:loc xlink:type="locator" xlink:label="loc_mtg_LossesIncurredAbstract" xlink:href="mtg-20201231.xsd#mtg_LossesIncurredAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_mtg_LossesIncurredAbstract" xlink:to="lab_mtg_LossesIncurredAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_InvestmentTypeAxis_0e594ce9-3ff6-4626-a3c1-0e72cdb23382_terseLabel_en-US" xlink:label="lab_us-gaap_InvestmentTypeAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Investment Type [Axis]</link:label>
    <link:label id="lab_us-gaap_InvestmentTypeAxis_label_en-US" xlink:label="lab_us-gaap_InvestmentTypeAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Investment Type [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeAxis" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_InvestmentTypeAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InvestmentTypeAxis" xlink:to="lab_us-gaap_InvestmentTypeAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_mtg_DefinedBenefitPlanSubtotal_ed9079a9-a48e-46ce-9eac-ebcf23beebc5_totalLabel_en-US" xlink:label="lab_mtg_DefinedBenefitPlanSubtotal" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Subtotal</link:label>
    <link:label id="lab_mtg_DefinedBenefitPlanSubtotal_label_en-US" xlink:label="lab_mtg_DefinedBenefitPlanSubtotal" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Defined Benefit Plan, Subtotal</link:label>
    <link:label id="lab_mtg_DefinedBenefitPlanSubtotal_documentation_en-US" xlink:label="lab_mtg_DefinedBenefitPlanSubtotal" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">The subtotal amount of net periodic benefit cost for defined benefit plans that may include the following components: service cost, interest cost, expected return on plan assets, and other adjustments.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_DefinedBenefitPlanSubtotal" xlink:href="mtg-20201231.xsd#mtg_DefinedBenefitPlanSubtotal"/>
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    <link:label id="lab_mtg_ReinsuranceTerminations_4e406c42-5b74-4a82-bc85-fdfd2ce856bd_negatedTerseLabel_en-US" xlink:label="lab_mtg_ReinsuranceTerminations" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Reinsurance terminations</link:label>
    <link:label id="lab_mtg_ReinsuranceTerminations_label_en-US" xlink:label="lab_mtg_ReinsuranceTerminations" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Reinsurance terminations</link:label>
    <link:label id="lab_mtg_ReinsuranceTerminations_documentation_en-US" xlink:label="lab_mtg_ReinsuranceTerminations" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Decrease in losses paid resulting from cancellations of reinsurance agreements, with no future premium ceded and funds for any incurred but unpaid losses transferred to the entity.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_mtg_ReinsuranceTerminations" xlink:href="mtg-20201231.xsd#mtg_ReinsuranceTerminations"/>
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    <link:label id="lab_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPortionAttributableToParent_29227d7f-2247-48a8-b4af-bcf733af7141_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPortionAttributableToParent" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Benefit plans adjustment</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPortionAttributableToParent_0f70d69c-99de-4ee3-a5cc-4384f795b1b1_negatedTotalLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPortionAttributableToParent" xlink:role="http://www.xbrl.org/2009/role/negatedTotalLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Net of taxes</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPortionAttributableToParent_label_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPortionAttributableToParent" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax and Reclassification Adjustment, Attributable to Parent</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPortionAttributableToParent" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPortionAttributableToParent"/>
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    <link:label id="lab_us-gaap_ScheduleOfAssumptionsUsedTableTextBlock_725d79cc-f034-4c42-9313-152ffcca222f_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfAssumptionsUsedTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Actuarial assumptions</link:label>
    <link:label id="lab_us-gaap_ScheduleOfAssumptionsUsedTableTextBlock_label_en-US" xlink:label="lab_us-gaap_ScheduleOfAssumptionsUsedTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Defined Benefit Plan, Assumptions [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAssumptionsUsedTableTextBlock" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfAssumptionsUsedTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfAssumptionsUsedTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfAssumptionsUsedTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_Depreciation_8bda15ce-0dcf-47f1-9d4f-0d3be0cf1795_terseLabel_en-US" xlink:label="lab_us-gaap_Depreciation" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Depreciation expense of home office and equipment</link:label>
    <link:label id="lab_us-gaap_Depreciation_label_en-US" xlink:label="lab_us-gaap_Depreciation" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Depreciation</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Depreciation" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_Depreciation"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_Depreciation" xlink:to="lab_us-gaap_Depreciation" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_LongtermDebtTypeAxis_ceebd9c0-2a38-492b-b5f9-88ccdd75fc4e_terseLabel_en-US" xlink:label="lab_us-gaap_LongtermDebtTypeAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Long-term Debt, Type [Axis]</link:label>
    <link:label id="lab_us-gaap_LongtermDebtTypeAxis_label_en-US" xlink:label="lab_us-gaap_LongtermDebtTypeAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Long-term Debt, Type [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis" xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongtermDebtTypeAxis" xlink:to="lab_us-gaap_LongtermDebtTypeAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AdditionalPaidInCapitalCommonStock_71919cf6-e9b1-49bc-bfc5-f05d142f99bb_terseLabel_en-US" xlink:label="lab_us-gaap_AdditionalPaidInCapitalCommonStock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Paid-in capital</link:label>
    <link:label id="lab_us-gaap_AdditionalPaidInCapitalCommonStock_label_en-US" xlink:label="lab_us-gaap_AdditionalPaidInCapitalCommonStock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xmlns:xml="http://www.w3.org/XML/1998/namespace" xml:lang="en-US">Additional Paid in Capital, Common Stock</link:label>
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