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  <xs:element id="sbsi_WeightedAverageMaturityAndInterestRatesOnRiskManagementInterestRateSwapsTableTextBlock" abstract="false" name="WeightedAverageMaturityAndInterestRatesOnRiskManagementInterestRateSwapsTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="sbsi_BorrowedFundsMaturitiesRepaymentsOfPrincipalInRollingYearTwo" abstract="false" name="BorrowedFundsMaturitiesRepaymentsOfPrincipalInRollingYearTwo" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="sbsi_MunicipalLoansMember" abstract="true" name="MunicipalLoansMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="sbsi_OffbalancesheetAllowanceforoffbalancesheetcreditexposuresTableTextBlock" abstract="false" name="OffbalancesheetAllowanceforoffbalancesheetcreditexposuresTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="sbsi_FinancingReceivableExcludingAccruedInterestRevolvingWriteoff" abstract="false" name="FinancingReceivableExcludingAccruedInterestRevolvingWriteoff" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="sbsi_SecuritiesTransferredUnrealizedLossNetOfTax" abstract="false" name="SecuritiesTransferredUnrealizedLossNetOfTax" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="sbsi_OCIDebtSecuritiesAvailableForSaleTransferToHeldToMaturityGainLossBeforeAdjustmentAndTax" abstract="false" name="OCIDebtSecuritiesAvailableForSaleTransferToHeldToMaturityGainLossBeforeAdjustmentAndTax" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="sbsi_FinancingReceivableCollateralDependent" abstract="false" name="FinancingReceivableCollateralDependent" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="sbsi_BorrowingsAverageAmountOutstanding" abstract="false" name="BorrowingsAverageAmountOutstanding" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="sbsi_AmortizationofUnrealizedGainsLossesonSecuritiesTransferredBetweenAvailableforSaleAndHeldtoMaturityDebtSecuritiesBeforeTax" abstract="false" name="AmortizationofUnrealizedGainsLossesonSecuritiesTransferredBetweenAvailableforSaleAndHeldtoMaturityDebtSecuritiesBeforeTax" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="sbsi_RepurchaseAgreementCounterpartyMaturityofAgreements" abstract="false" name="RepurchaseAgreementCounterpartyMaturityofAgreements" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="sbsi_SouthsideStatutoryTrustVMember" abstract="true" name="SouthsideStatutoryTrustVMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="sbsi_FederalHomeLoanBankStockWithOtherThanTemporaryImpairment" abstract="false" name="FederalHomeLoanBankStockWithOtherThanTemporaryImpairment" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="sbsi_ScheduleOfAvailableForSaleAndHeldToMaturitySecuritiesTable" abstract="true" name="ScheduleOfAvailableForSaleAndHeldToMaturitySecuritiesTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="sbsi_DerivativeWeightedAveragePayRate" abstract="false" name="DerivativeWeightedAveragePayRate" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="sbsi_SouthsideStatutoryTrustIIInetofunamortizeddebtissuancecostsMember" abstract="true" name="SouthsideStatutoryTrustIIInetofunamortizeddebtissuancecostsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="sbsi_Numberofoutstandinglettersofcredit" abstract="false" name="Numberofoutstandinglettersofcredit" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="sbsi_LettersOfCreditFhlbAsCollateral" abstract="false" name="LettersOfCreditFhlbAsCollateral" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="sbsi_CommercialRealEstateFarmLand" abstract="false" name="CommercialRealEstateFarmLand" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="sbsi_OtherComprehensiveIncomeLossDefinedBenefitPlanGainLossandPriorServiceCostCreditReclassificationAdjustmentfromAOCIbeforeTax" abstract="false" name="OtherComprehensiveIncomeLossDefinedBenefitPlanGainLossandPriorServiceCostCreditReclassificationAdjustmentfromAOCIbeforeTax" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="sbsi_AdjustmentToPensionLiability" abstract="false" name="AdjustmentToPensionLiability" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="sbsi_BorrowedFundsMaturitiesRepaymentsOfPrincipalInRollingYearFive" abstract="false" name="BorrowedFundsMaturitiesRepaymentsOfPrincipalInRollingYearFive" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="sbsi_ComericaBankMember" abstract="true" name="ComericaBankMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="sbsi_DemandDepositOverdraftsMember" abstract="true" name="DemandDepositOverdraftsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
