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      <link:linkbaseRef xlink:type="simple" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:role="http://www.xbrl.org/2003/role/labelLinkbaseRef" xlink:href="utl-20160331_lab.xml" xlink:title="Label Links, all"/>
      <link:linkbaseRef xlink:type="simple" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:role="http://www.xbrl.org/2003/role/presentationLinkbaseRef" xlink:href="utl-20160331_pre.xml" xlink:title="Presentation Links, all"/>
    </appinfo>
  </annotation>
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  <import namespace="http://www.xbrl.org/2003/linkbase" schemaLocation="http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd"/>
  <import namespace="http://fasb.org/us-types/2015-01-31" schemaLocation="http://xbrl.fasb.org/us-gaap/2015/elts/us-types-2015-01-31.xsd"/>
  <import namespace="http://www.xbrl.org/dtr/type/non-numeric" schemaLocation="http://www.xbrl.org/dtr/type/nonNumeric-2009-12-16.xsd"/>
  <import namespace="http://www.xbrl.org/dtr/type/numeric" schemaLocation="http://www.xbrl.org/dtr/type/numeric-2009-12-16.xsd"/>
  <import namespace="http://xbrl.org/2005/xbrldt" schemaLocation="http://www.xbrl.org/2005/xbrldt-2005.xsd"/>
  <import namespace="http://fasb.org/us-gaap/2015-01-31" schemaLocation="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd"/>
  <import namespace="http://xbrl.sec.gov/country/2013-01-31" schemaLocation="http://xbrl.sec.gov/country/2013/country-2013-01-31.xsd"/>
  <import namespace="http://xbrl.sec.gov/currency/2014-01-31" schemaLocation="http://xbrl.sec.gov/currency/2014/currency-2014-01-31.xsd"/>
  <import namespace="http://xbrl.sec.gov/dei/2014-01-31" schemaLocation="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd"/>
  <import namespace="http://xbrl.sec.gov/exch/2015-01-31" schemaLocation="http://xbrl.sec.gov/exch/2015/exch-2015-01-31.xsd"/>
  <import namespace="http://xbrl.sec.gov/invest/2013-01-31" schemaLocation="http://xbrl.sec.gov/invest/2013/invest-2013-01-31.xsd"/>
  <import namespace="http://xbrl.sec.gov/naics/2011-01-31" schemaLocation="http://xbrl.sec.gov/naics/2011/naics-2011-01-31.xsd"/>
  <import namespace="http://xbrl.sec.gov/sic/2011-01-31" schemaLocation="http://xbrl.sec.gov/sic/2011/sic-2011-01-31.xsd"/>
  <import namespace="http://xbrl.sec.gov/stpr/2011-01-31" schemaLocation="http://xbrl.sec.gov/stpr/2011/stpr-2011-01-31.xsd"/>
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  <element name="AmendmentEffectiveDate" id="utl_AmendmentEffectiveDate" type="xbrli:dateItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="BenefitPlanCostsMember" id="utl_BenefitPlanCostsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
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  <element name="ChangeInDeferredRegulatoryAndOtherCharges" id="utl_ChangeInDeferredRegulatoryAndOtherCharges" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ChangeInNetIncomeLossDueToChangeInEstimates" id="utl_ChangeInNetIncomeLossDueToChangeInEstimates" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
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  <element name="DebtIssuanceCostsPolicyTextBlock" id="utl_DebtIssuanceCostsPolicyTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
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  <element name="DividendAndDistributionReinvestmentAndSharePurchasePlanMember" id="utl_DividendAndDistributionReinvestmentAndSharePurchasePlanMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
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  <element name="EffectiveDate" id="utl_EffectiveDate" type="xbrli:dateItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ElectricityMember" id="utl_ElectricityMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ElectricUtilitiesMember" id="utl_ElectricUtilitiesMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="EnergyMarketingContractLiabilities" id="utl_EnergyMarketingContractLiabilities" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="EnvironmentalCostsRateCaseCostsAndOtherExpendituresMember" id="utl_EnvironmentalCostsRateCaseCostsAndOtherExpendituresMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="EnvironmentalMattersMember" id="utl_EnvironmentalMattersMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="FairValueOfRestrictedStockUnitsSettledInCash" id="utl_FairValueOfRestrictedStockUnitsSettledInCash" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
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  <element name="FirstAmendmentMember" id="utl_FirstAmendmentMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="FirstMortgageBondsEightPointFourNinePercentDueOctoberFourteenTwentyTwentyFourMember" id="utl_FirstMortgageBondsEightPointFourNinePercentDueOctoberFourteenTwentyTwentyFourMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="FirstMortgageBondsEightPointZeroZeroPercentDueMayOneTwentyThirtyOneMember" id="utl_FirstMortgageBondsEightPointZeroZeroPercentDueMayOneTwentyThirtyOneMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="FirstMortgageBondsFivePointTwoFourPercentDueMarchTwoTwentyTwentyMember" id="utl_FirstMortgageBondsFivePointTwoFourPercentDueMarchTwoTwentyTwentyMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="FirstMortgageBondsSixPointNineSixPercentDueSeptemberOneTwentyTwentyEightMember" id="utl_FirstMortgageBondsSixPointNineSixPercentDueSeptemberOneTwentyTwentyEightMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="FirstMortgageBondsSixPointThreeTwoPercentDueSeptemberFifteenTwentyThirtySixMember" id="utl_FirstMortgageBondsSixPointThreeTwoPercentDueSeptemberFifteenTwentyThirtySixMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="FitchburgGasAndElectricLightCompanyMember" id="utl_FitchburgGasAndElectricLightCompanyMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="GasPipelineRefundMember" id="utl_GasPipelineRefundMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="GasSegmentMember" id="utl_GasSegmentMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="GasTransportationAndStorageMember" id="utl_GasTransportationAndStorageMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="GracePeriodForIssuingOrReceivingRefunds" id="utl_GracePeriodForIssuingOrReceivingRefunds" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="GraniteStateGasTransmissionIncMember" id="utl_GraniteStateGasTransmissionIncMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
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  <element name="GroupFourMember" id="utl_GroupFourMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
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  <element name="GroupSixMember" id="utl_GroupSixMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="GroupThreeMember" id="utl_GroupThreeMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
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  <element name="HedgingObligationsMember" id="utl_HedgingObligationsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="IncomeTaxesMember" id="utl_IncomeTaxesMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="IncreaseDecreaseInGasInventoryFinancing" id="utl_IncreaseDecreaseInGasInventoryFinancing" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="IncreaseDecreaseInLongTermDebt" id="utl_IncreaseDecreaseInLongTermDebt" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
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  <element name="InterestRateAllowedOnUnrecoveredStormCosts" id="utl_InterestRateAllowedOnUnrecoveredStormCosts" type="num:percentItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LengthOfPipeline" id="utl_LengthOfPipeline" type="num:lengthItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LetterOfCreditFacilityAndBankGuaranteesOutstanding" id="utl_LetterOfCreditFacilityAndBankGuaranteesOutstanding" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LineOfCreditFacilityMaximumIncreaseToAggregateCommitments" id="utl_LineOfCreditFacilityMaximumIncreaseToAggregateCommitments" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NaturalGasAndOilProvedReservesMultiplierToCoverFairValueOfTransactionsOutstanding" id="utl_NaturalGasAndOilProvedReservesMultiplierToCoverFairValueOfTransactionsOutstanding" type="num:volumeItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NatureOfOperationsPolicyTextBlock" id="utl_NatureOfOperationsPolicyTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NetOperatingLossAndTaxCreditCarryForward" id="utl_NetOperatingLossAndTaxCreditCarryForward" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NetOperatingLossCarryforwardsExpirationYear" id="utl_NetOperatingLossCarryforwardsExpirationYear" type="xbrli:gYearItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NewEnglandMember" id="utl_NewEnglandMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
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  <element name="NorthernUtilitiesIncMember" id="utl_NorthernUtilitiesIncMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NotesFivePointNineZeroPercentDueDecemberFifteenTwentyThirtyMember" id="utl_NotesFivePointNineZeroPercentDueDecemberFifteenTwentyThirtyMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NotesSevenPointNineEightPercentDueJuneOneTwentyThirtyOneMember" id="utl_NotesSevenPointNineEightPercentDueJuneOneTwentyThirtyOneMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NotesSevenPointThreeSevenPercentDueJanuaryFifteenTwentyTwentyNineMember" id="utl_NotesSevenPointThreeSevenPercentDueJanuaryFifteenTwentyTwentyNineMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NotesSixPointSevenFivePercentDueNovemberThirtyTwentyTwentyThreeMember" id="utl_NotesSixPointSevenFivePercentDueNovemberThirtyTwentyTwentyThreeMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NotesSixPointSevenNinePercentDueOctoberFifteenTwentyTwentyFiveMember" id="utl_NotesSixPointSevenNinePercentDueOctoberFifteenTwentyTwentyFiveMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
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  <element name="PercentageOfFullyVestedRestrictedStockUnitsThatDirectorsWillReceiveInCashWhenSettled" id="utl_PercentageOfFullyVestedRestrictedStockUnitsThatDirectorsWillReceiveInCashWhenSettled" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
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  <element name="PostretirementBenefitMember" id="utl_PostretirementBenefitMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ProceedsFromRepaymentsOfDebtAndCapitalLeaseObligations" id="utl_ProceedsFromRepaymentsOfDebtAndCapitalLeaseObligations" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
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  <element name="PublicUtilitiesPropertyPlantAndEquipmentGas" id="utl_PublicUtilitiesPropertyPlantAndEquipmentGas" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
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  <element name="RegulatoryTrackerMechanismsMember" id="utl_RegulatoryTrackerMechanismsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
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  <element name="RenewableEnergyPortfolioRequirementMember" id="utl_RenewableEnergyPortfolioRequirementMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfOtherAccountsReceivableTableTextBlock" id="utl_ScheduleOfOtherAccountsReceivableTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfStockOptionsLineItems" id="utl_ScheduleOfStockOptionsLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfStockOptionsTable" id="utl_ScheduleOfStockOptionsTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
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  <element name="UnitilRealtyCorpMember" id="utl_UnitilRealtyCorpMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="UnitilServiceCorpMember" id="utl_UnitilServiceCorpMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
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</schema>
