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  <xs:element id="wal_DepositsEarningsCreditAndReferralCostsOther" abstract="false" name="DepositsEarningsCreditAndReferralCostsOther" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wal_DebtTable" abstract="true" name="DebtTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="wal_CreditLinkedNotesMember" abstract="true" name="CreditLinkedNotesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_DebtLineItems" abstract="true" name="DebtLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="wal_LongTermFHLBAdvanceIssuedJanuary302026Member" abstract="true" name="LongTermFHLBAdvanceIssuedJanuary302026Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_LongTermFHLBAdvanceIssuedOctober302025Member" abstract="true" name="LongTermFHLBAdvanceIssuedOctober302025Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_LongTermFHLBAdvanceIssuedNovember262025Member" abstract="true" name="LongTermFHLBAdvanceIssuedNovember262025Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_CreditLinkedNotesMaturingOctober2052Member" abstract="true" name="CreditLinkedNotesMaturingOctober2052Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_CreditLinkedNotesMaturingApril2052Member" abstract="true" name="CreditLinkedNotesMaturingApril2052Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_CreditLinkedNotesMaturingJuly2059Member" abstract="true" name="CreditLinkedNotesMaturingJuly2059Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_DebtInstrumentReferencePoolBalance" abstract="false" name="DebtInstrumentReferencePoolBalance" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wal_DebtInstrumentClassesOfNotesNumber" abstract="false" name="DebtInstrumentClassesOfNotesNumber" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="wal_SubordinatedDebenturesMaturingJune2031Member" abstract="true" name="SubordinatedDebenturesMaturingJune2031Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_SubordinatedDebenturesMaturingNovember2035Member" abstract="true" name="SubordinatedDebenturesMaturingNovember2035Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_NumberofStatutoryBusinessTrustsFormedorAcquired" abstract="false" name="NumberofStatutoryBusinessTrustsFormedorAcquired" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="wal_CashSettledStockUnitsMember" abstract="true" name="CashSettledStockUnitsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_DeferredStockUnitsMember" abstract="true" name="DeferredStockUnitsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_GrantYear2024Member" abstract="true" name="GrantYear2024Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_GrantYear2023Member" abstract="true" name="GrantYear2023Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_GrantYear2022Member" abstract="true" name="GrantYear2022Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_BWRealEstateInc.Member" abstract="true" name="BWRealEstateInc.Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_ShareRepurchaseProgramMember" abstract="true" name="ShareRepurchaseProgramMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValueAggregate" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValueAggregate" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wal_EquityPreferredStockOwnershipInterestRatio" abstract="false" name="EquityPreferredStockOwnershipInterestRatio" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="wal_PreferredStockRateResetPeriod" abstract="false" name="PreferredStockRateResetPeriod" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="wal_SaleOfStockConsiderationReceivedOnTransactionGross" abstract="false" name="SaleOfStockConsiderationReceivedOnTransactionGross" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wal_InterestRateSwapTerminatedMember" abstract="true" name="InterestRateSwapTerminatedMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_PortfolioLayerMethodSwapsMember" abstract="true" name="PortfolioLayerMethodSwapsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_DerivativeNotionalAmountTerminatedDuringPeriod" abstract="false" name="DerivativeNotionalAmountTerminatedDuringPeriod" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wal_HedgedAssetFairValueHedgePortfolioLayerMethodHedgedLayerFairValueCumulativeIncreaseDecreaseDuringPeriod" abstract="false" name="HedgedAssetFairValueHedgePortfolioLayerMethodHedgedLayerFairValueCumulativeIncreaseDecreaseDuringPeriod" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wal_LoansHeldForInvestmentsMember" abstract="true" name="LoansHeldForInvestmentsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_InvestmentSecuritiesAFSMember" abstract="true" name="InvestmentSecuritiesAFSMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_QualifyingDebtMember" abstract="true" name="QualifyingDebtMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_PrepayableFixedRateLoansMember" abstract="true" name="PrepayableFixedRateLoansMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_ForwardPurchaseAndSalesContractsMember" abstract="true" name="ForwardPurchaseAndSalesContractsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_FuturesPurchaseAndSaleContractsMember" abstract="true" name="FuturesPurchaseAndSaleContractsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_RiskParticipationAgreementsMember" abstract="true" name="RiskParticipationAgreementsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_EquityWarrantsMember" abstract="true" name="EquityWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_DerivativeNettingAdjustmentsNotionalAmount" abstract="false" name="DerivativeNettingAdjustmentsNotionalAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wal_DerivativeNettingAdjustmentsAssets" abstract="false" name="DerivativeNettingAdjustmentsAssets" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wal_DerivativeNettingAdjustmentsLiabilities" abstract="false" name="DerivativeNettingAdjustmentsLiabilities" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wal_DerivativeAssetSubjectToMasterNettingArrangementCollateralObligationToReturnCashOffsetAgainstDerivativeAssetNetOfAdjustments" abstract="false" name="DerivativeAssetSubjectToMasterNettingArrangementCollateralObligationToReturnCashOffsetAgainstDerivativeAssetNetOfAdjustments" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wal_NetGainOnLoanOriginationAndSaleActivitiesMember" abstract="true" name="NetGainOnLoanOriginationAndSaleActivitiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_LoanServicingFeesNetMember" abstract="true" name="LoanServicingFeesNetMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_FairValueGainAdjustmentsNetMember" abstract="true" name="FairValueGainAdjustmentsNetMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_IncomeLossFromEquityInvestmentsMember" abstract="true" name="IncomeLossFromEquityInvestmentsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_OtherNonInterestIncomeMember" abstract="true" name="OtherNonInterestIncomeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_CommercialAndIndustrialMember" abstract="true" name="CommercialAndIndustrialMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_PercentageOfCommercialRealEstateLoansOccupiedByOwners" abstract="false" name="PercentageOfCommercialRealEstateLoansOccupiedByOwners" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="wal_CreditCardCommitmentsAndFinancialGuaranteesMember" abstract="true" name="CreditCardCommitmentsAndFinancialGuaranteesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_UnsecuredLoanCommitments" abstract="false" name="UnsecuredLoanCommitments" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wal_UnsecuredLettersOfCredit" abstract="false" name="UnsecuredLettersOfCredit" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wal_LoansHeldForSaleMember" abstract="true" name="LoansHeldForSaleMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_IRLCSettlementsUponAcquisitionOrOrigination" abstract="false" name="IRLCSettlementsUponAcquisitionOrOrigination" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wal_RealizationOfCashFlows" abstract="false" name="RealizationOfCashFlows" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wal_ThirdPartyAppraisalMember" abstract="true" name="ThirdPartyAppraisalMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_DiscountRateMember" abstract="true" name="DiscountRateMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_ScheduledCashCollectionsMember" abstract="true" name="ScheduledCashCollectionsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_ProceedsfromNonRealEstateCollateralMember" abstract="true" name="ProceedsfromNonRealEstateCollateralMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_OptionAdjustedSpreadMember" abstract="true" name="OptionAdjustedSpreadMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_ConditionalPrepaymentRateMember" abstract="true" name="ConditionalPrepaymentRateMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_RecaptureRateMember" abstract="true" name="RecaptureRateMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_ServicingFeeRateMember" abstract="true" name="ServicingFeeRateMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_CostToServiceMember" abstract="true" name="CostToServiceMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_LifetimeLiquidationProbabilityMember" abstract="true" name="LifetimeLiquidationProbabilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_ServicingFeeMultipleMember" abstract="true" name="ServicingFeeMultipleMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_PullThroughRateMember" abstract="true" name="PullThroughRateMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_MeasurementInputTimeToExpirationMember" abstract="true" name="MeasurementInputTimeToExpirationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_ValuationTechniqueCollateralMethodMember" abstract="true" name="ValuationTechniqueCollateralMethodMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_CollateralDependentLoansNetofAllowance" abstract="false" name="CollateralDependentLoansNetofAllowance" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wal_CollateralDependentLoansMeasurementInput" abstract="false" name="CollateralDependentLoansMeasurementInput" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="wal_RepossessedAssetsMeasurementInput" abstract="false" name="RepossessedAssetsMeasurementInput" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="wal_FairValueOptionLoansHeldAsAssetsCurrentThrough89Days" abstract="false" name="FairValueOptionLoansHeldAsAssetsCurrentThrough89Days" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wal_FairValueOptionLoansHeldAsAssetsUPBCurrentThrough89Days" abstract="false" name="FairValueOptionLoansHeldAsAssetsUPBCurrentThrough89Days" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wal_FairValueOptionLoansHeldAsAssetsCurrentThrough89DaysAggregateDifference" abstract="false" name="FairValueOptionLoansHeldAsAssetsCurrentThrough89DaysAggregateDifference" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wal_FairValueOptionLoansHeldAsAssetsUPB90DaysOrMorePastDue" abstract="false" name="FairValueOptionLoansHeldAsAssetsUPB90DaysOrMorePastDue" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wal_FairValueOptionLoansHeldAsAssets" abstract="false" name="FairValueOptionLoansHeldAsAssets" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wal_FairValueOptionLoansHeldAsAssetsUPB" abstract="false" name="FairValueOptionLoansHeldAsAssetsUPB" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wal_PercentageOfBasisSpreadOnVariableRate" abstract="false" name="PercentageOfBasisSpreadOnVariableRate" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="wal_CollateralDependentLoansAllowance" abstract="false" name="CollateralDependentLoansAllowance" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wal_CommercialSegmentMember" abstract="true" name="CommercialSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_ConsumerRelatedSegmentMember" abstract="true" name="ConsumerRelatedSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_CorporateAndOtherSegmentMember" abstract="true" name="CorporateAndOtherSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_GoodwillAssignedPercentage" abstract="false" name="GoodwillAssignedPercentage" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="wal_EquityCapitalAssignedPercentage" abstract="false" name="EquityCapitalAssignedPercentage" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="wal_CashCashEquivalentsandInvestmentSecurities" abstract="false" name="CashCashEquivalentsandInvestmentSecurities" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wal_OtherAssetsSegment" abstract="false" name="OtherAssetsSegment" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wal_BorrowingsandQualifyingDebt" abstract="false" name="BorrowingsandQualifyingDebt" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wal_OtherLiabilitiesSegment" abstract="false" name="OtherLiabilitiesSegment" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wal_LiabilitiesAndEquityExcludingExcessFundsProvidedUsed" abstract="false" name="LiabilitiesAndEquityExcludingExcessFundsProvidedUsed" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wal_ExcessFundsProvidedbyUsedinSegmentBasis" abstract="false" name="ExcessFundsProvidedbyUsedinSegmentBasis" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wal_OtherNoninterestExpenseSegments" abstract="false" name="OtherNoninterestExpenseSegments" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wal_BankingServiceChargesAndFeesMember" abstract="true" name="BankingServiceChargesAndFeesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_InterchangeFeesMember" abstract="true" name="InterchangeFeesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_DisbursementsAndEscrowFeesMember" abstract="true" name="DisbursementsAndEscrowFeesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wal_OtherFeesMember" abstract="true" name="OtherFeesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
