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  <xs:element id="adt_ScheduleOfSubscriberSystemAssetsTableTextBlock" abstract="false" name="ScheduleOfSubscriberSystemAssetsTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="adt_ScheduleOfSubscriberSystemAssetAndDeferredSubscriberAcquisitionCostsOfDepreciationAndAmortizationTableTextBlock" abstract="false" name="ScheduleOfSubscriberSystemAssetAndDeferredSubscriberAcquisitionCostsOfDepreciationAndAmortizationTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="adt_ScheduleofCarryingValuesandEstimatedFairValuesofDebtInstrumentsandSecuritiesTableTextBlock" abstract="false" name="ScheduleofCarryingValuesandEstimatedFairValuesofDebtInstrumentsandSecuritiesTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="adt_ScheduleOfCarryingValuesAndFairValuesOfRetailInstallmentContractReceivablesTableTextBlock" abstract="false" name="ScheduleOfCarryingValuesAndFairValuesOfRetailInstallmentContractReceivablesTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="adt_ScheduleOfUnbilledRetailInstallmentContractReceivablesNetTableTextBlock" abstract="false" name="ScheduleOfUnbilledRetailInstallmentContractReceivablesNetTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="adt_ScheduleOfUnrealizedInterestRateDerivativesTableTextBlock" abstract="false" name="ScheduleOfUnrealizedInterestRateDerivativesTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="adt_LeasesOperatingandFinanceTableTextBlock" abstract="false" name="LeasesOperatingandFinanceTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="adt_CapitalizedContractCostsIncurredButNotYetPaid" abstract="false" name="CapitalizedContractCostsIncurredButNotYetPaid" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="adt_RevenuefromContractwithCustomerTermofCustomerRelationship" abstract="false" name="RevenuefromContractwithCustomerTermofCustomerRelationship" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="adt_SubscriberSystemAssetsGross" abstract="false" name="SubscriberSystemAssetsGross" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="adt_SubscriberSystemAssetsAccumulatedDepreciation" abstract="false" name="SubscriberSystemAssetsAccumulatedDepreciation" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="adt_SubscriberSystemAssetsDepreciationExpense" abstract="false" name="SubscriberSystemAssetsDepreciationExpense" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="adt_AccountingPoliciesTable" abstract="true" name="AccountingPoliciesTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="adt_AccountingPoliciesLineItems" abstract="true" name="AccountingPoliciesLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="adt_RetailInstallmentContractMember" abstract="true" name="RetailInstallmentContractMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_RecurringMonthlyRevenueMember" abstract="true" name="RecurringMonthlyRevenueMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_OtherRelatedServicesMember" abstract="true" name="OtherRelatedServicesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_InstallationAndOtherRevenueMember" abstract="true" name="InstallationAndOtherRevenueMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_AmortizationOfDeferredSubscriberAcquisitionRevenueMember" abstract="true" name="AmortizationOfDeferredSubscriberAcquisitionRevenueMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_ContractWithCustomerLiabilityAdditionalLiabilitiesRecognized" abstract="false" name="ContractWithCustomerLiabilityAdditionalLiabilitiesRecognized" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="adt_FICOScoreGradeHighMember" abstract="true" name="FICOScoreGradeHighMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_FICOScoreGradeMediumMember" abstract="true" name="FICOScoreGradeMediumMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_FICOScoreGradeLowMember" abstract="true" name="FICOScoreGradeLowMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_ReportableSegmentMember" abstract="true" name="ReportableSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_CostCustomerService" abstract="false" name="CostCustomerService" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="adt_ShareBasedPaymentArrangementExpenseAdjusted" abstract="false" name="ShareBasedPaymentArrangementExpenseAdjusted" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="adt_SegmentReportingOtherItemsInSellingGeneralAndAdministrativeExpense" abstract="false" name="SegmentReportingOtherItemsInSellingGeneralAndAdministrativeExpense" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="adt_SegmentReportingOtherNetAmount" abstract="false" name="SegmentReportingOtherNetAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="adt_OriginAIMember" abstract="true" name="OriginAIMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_DealerRelationshipsMember" abstract="true" name="DealerRelationshipsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_FirstLienTermLoanBDue2030Member" abstract="true" name="FirstLienTermLoanBDue2030Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_FirstLienTermLoanB2Due2032Member" abstract="true" name="FirstLienTermLoanB2Due2032Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_FirstLienRevolvingCreditFacilityMember" abstract="true" name="FirstLienRevolvingCreditFacilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_FirstLienTermLoanADue2030Member" abstract="true" name="FirstLienTermLoanADue2030Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_FirstLienNotesDue2026Member" abstract="true" name="FirstLienNotesDue2026Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_FirstLienNotesDue2027Member" abstract="true" name="FirstLienNotesDue2027Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_FirstLienNotesDue2029Member" abstract="true" name="FirstLienNotesDue2029Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_FirstLienNotesDue2033Member" abstract="true" name="FirstLienNotesDue2033Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_ADTNotesdue2032Member" abstract="true" name="ADTNotesdue2032Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_ADTNotesdue2042Member" abstract="true" name="ADTNotesdue2042Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_ReceivablesFacilityMember" abstract="true" name="ReceivablesFacilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_CostOfFundRateCOFMember" abstract="true" name="CostOfFundRateCOFMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_AccretionofPurchaseAccountingFairValueAdjustmentDebt" abstract="false" name="AccretionofPurchaseAccountingFairValueAdjustmentDebt" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="adt_TermLoanADue2030Member" abstract="true" name="TermLoanADue2030Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_October2019NotDesignatedMember" abstract="true" name="October2019NotDesignatedMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_March2023NotDesignatedMember" abstract="true" name="March2023NotDesignatedMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_April2023NotDesignatedMember" abstract="true" name="April2023NotDesignatedMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_December2023NotDesignatedMember" abstract="true" name="December2023NotDesignatedMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_June2025CashFlowHedgeMember" abstract="true" name="June2025CashFlowHedgeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_July2025CashFlowHedgeMember" abstract="true" name="July2025CashFlowHedgeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_July2025NotDesignatedMember" abstract="true" name="July2025NotDesignatedMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_September2025CashFlowHedgeMember" abstract="true" name="September2025CashFlowHedgeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_October2025CashFlowHedgeMaturing2030Member" abstract="true" name="October2025CashFlowHedgeMaturing2030Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_October2025CashFlowHedgeMaturing2032Member" abstract="true" name="October2025CashFlowHedgeMaturing2032Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_October2025CashFlowHedgeMaturing2027Member" abstract="true" name="October2025CashFlowHedgeMaturing2027Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_ApolloMember" abstract="true" name="ApolloMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_A2026ShareRepurchasePlanMember" abstract="true" name="A2026ShareRepurchasePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_A2025ShareRepurchasePlanMember" abstract="true" name="A2025ShareRepurchasePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_NumberOfClassOfCommonStock" abstract="false" name="NumberOfClassOfCommonStock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="adt_ShareRepurchaseProgramLengthOfProgram" abstract="false" name="ShareRepurchaseProgramLengthOfProgram" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="adt_ModifiedAwardsMember" abstract="true" name="ModifiedAwardsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_SharebasedCompensation2018PlanMember" abstract="true" name="SharebasedCompensation2018PlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_DilutiveSecuritiesDiscontinuedOperationsEffectOnBasicEarningsPerShare" abstract="false" name="DilutiveSecuritiesDiscontinuedOperationsEffectOnBasicEarningsPerShare" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="adt_GoogleMember" abstract="true" name="GoogleMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_FirstTwoYearsMember" abstract="true" name="FirstTwoYearsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_NextTwoYearsMember" abstract="true" name="NextTwoYearsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_LastThreeYearsMember" abstract="true" name="LastThreeYearsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_InsuredClaimsMember" abstract="true" name="InsuredClaimsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_CollaborativeArrangementFutureMilestoneContributions" abstract="false" name="CollaborativeArrangementFutureMilestoneContributions" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="adt_CollaborativeArrangementAdditionalFutureMilestoneContributions" abstract="false" name="CollaborativeArrangementAdditionalFutureMilestoneContributions" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="adt_CollaborativeArrangementExpenseReimbursementApproved" abstract="false" name="CollaborativeArrangementExpenseReimbursementApproved" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="adt_PurchaseObligationToBePaidYearOneAndTwo" abstract="false" name="PurchaseObligationToBePaidYearOneAndTwo" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="adt_PurchaseObligationToBePaidYearThreeAndFour" abstract="false" name="PurchaseObligationToBePaidYearThreeAndFour" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="adt_PurchaseObligationToBePaidAfterYearFour" abstract="false" name="PurchaseObligationToBePaidAfterYearFour" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="adt_PurchaseObligationCancelationFeePercentageOfTotalRemainingAmount" abstract="false" name="PurchaseObligationCancelationFeePercentageOfTotalRemainingAmount" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="adt_OperatingLeaseRightofUseAssetsCurrent" abstract="false" name="OperatingLeaseRightofUseAssetsCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="adt_LeasedAssets" abstract="false" name="LeasedAssets" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="adt_LeaseLiability" abstract="false" name="LeaseLiability" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="adt_May2026OfferingMember" abstract="true" name="May2026OfferingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_March2025OfferingMember" abstract="true" name="March2025OfferingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_June2025ApolloSaleMember" abstract="true" name="June2025ApolloSaleMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_TermLoanAFacilityMember" abstract="true" name="TermLoanAFacilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_FleetManagementAgreementMember" abstract="true" name="FleetManagementAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_ADTMember" abstract="true" name="ADTMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="adt_StateFarmFireCasualtyCompanyMember" abstract="true" name="StateFarmFireCasualtyCompanyMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
