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  <xs:element id="ptlo_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndExpectedToVestWeightedAverageRemainingContractualTerms" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndExpectedToVestWeightedAverageRemainingContractualTerms" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="ptlo_NumberOfLeasedProperties" abstract="false" name="NumberOfLeasedProperties" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="ptlo_RepaymentOfStockSubscriptionReceivable" abstract="false" name="RepaymentOfStockSubscriptionReceivable" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ptlo_PaymentsForRepurchaseOfEquityHeldBySubsidiaries" abstract="false" name="PaymentsForRepurchaseOfEquityHeldBySubsidiaries" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ptlo_PaymentsForShareBasedAwardsCashBonus" abstract="false" name="PaymentsForShareBasedAwardsCashBonus" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ptlo_AccruedPayrollTaxesCARESAct" abstract="false" name="AccruedPayrollTaxesCARESAct" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ptlo_LineOfCreditFacilityFrontingFeePercentage" abstract="false" name="LineOfCreditFacilityFrontingFeePercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="ptlo_IncomeTaxCreditsAndAdjustmentsCARESAct" abstract="false" name="IncomeTaxCreditsAndAdjustmentsCARESAct" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ptlo_ProceedsFromPaycheckProtectionProgramLoanCARESAct" abstract="false" name="ProceedsFromPaycheckProtectionProgramLoanCARESAct" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ptlo_ConsultingFeesAnnualContractualAmount" abstract="false" name="ConsultingFeesAnnualContractualAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ptlo_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedOutstandingWeightedAverageRemainingContractualTerm" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedOutstandingWeightedAverageRemainingContractualTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="ptlo_SecondLienTermB3LoansMember" abstract="true" name="SecondLienTermB3LoansMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ptlo_NumberOfFoodProductionCommissaries" abstract="false" name="NumberOfFoodProductionCommissaries" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="ptlo_ShareBasedCompensationArrangementByShareBasedPaymentAwardThresholdVolumeWeightedAveragePriceForVestingOfAwards" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardThresholdVolumeWeightedAveragePriceForVestingOfAwards" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="ptlo_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisableNumber" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisableNumber" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="ptlo_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedOutstandingAggregateIntrinsicValue" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedOutstandingAggregateIntrinsicValue" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ptlo_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageRemainingContractualTerms" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageRemainingContractualTerms" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="ptlo_TaxReceivableAgreementTaxPayablePercentOfTaxSavings" abstract="false" name="TaxReceivableAgreementTaxPayablePercentOfTaxSavings" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="ptlo_PortillosOpcoMember" abstract="true" name="PortillosOpcoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ptlo_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueVestedAndExpectedToVest" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueVestedAndExpectedToVest" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ptlo_CommonStockSharesSubscribedButUnissuedRepaymentOfSubscriptionReceivable" abstract="false" name="CommonStockSharesSubscribedButUnissuedRepaymentOfSubscriptionReceivable" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ptlo_NumberOfNonTraditionalRestaurant" abstract="false" name="NumberOfNonTraditionalRestaurant" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
</xs:schema>
