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  xmlns:wafd="http://wafdbank.com/20261102"
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        <period>
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            <endDate>2026-11-02</endDate>
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            <endDate>2026-11-02</endDate>
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    </context>
    <dei:AmendmentFlag
      contextRef="c20261102to20261102"
      id="Fact_881c36adc6854d9b8eb3738e4bda75bc">false</dei:AmendmentFlag>
    <dei:EntityCentralIndexKey
      contextRef="c20261102to20261102"
      id="Fact_029d4bbdc32f422f8e0dd62791f69869">0000936528</dei:EntityCentralIndexKey>
    <dei:DocumentType
      contextRef="c20261102to20261102"
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    <dei:DocumentPeriodEndDate
      contextRef="c20261102to20261102"
      id="Fact_8923baa5c0b24818b1ca7b9b981e930f">2026-11-02</dei:DocumentPeriodEndDate>
    <dei:EntityRegistrantName
      contextRef="c20261102to20261102"
      id="Fact_4a8d10cfddb844d998b0c54832f95319">WAFD, INC.</dei:EntityRegistrantName>
    <dei:EntityIncorporationStateCountryCode
      contextRef="c20261102to20261102"
      id="Fact_9c5172e9e46e4893978b78605f6afd0a">WA</dei:EntityIncorporationStateCountryCode>
    <dei:EntityFileNumber
      contextRef="c20261102to20261102"
      id="Fact_784d62ebcb504202bb36b9a08f28f6db">001-34654</dei:EntityFileNumber>
    <dei:EntityTaxIdentificationNumber
      contextRef="c20261102to20261102"
      id="Fact_1546c3d40f664cad95c4e9d78da9b88b">91-1661606</dei:EntityTaxIdentificationNumber>
    <dei:EntityAddressAddressLine1
      contextRef="c20261102to20261102"
      id="Fact_43116fa203d5496c8b4c7fc7b79ebb9c">425 Pike Street</dei:EntityAddressAddressLine1>
    <dei:EntityAddressCityOrTown
      contextRef="c20261102to20261102"
      id="Fact_710a4141ef384048a94fc507bdc300bf">Seattle</dei:EntityAddressCityOrTown>
    <dei:EntityAddressStateOrProvince
      contextRef="c20261102to20261102"
      id="Fact_e3104368e1174132b3919d2bb6cecf24">WA</dei:EntityAddressStateOrProvince>
    <dei:EntityAddressPostalZipCode
      contextRef="c20261102to20261102"
      id="Fact_8a4cddd3a6504f32866e89f7e8e3849a">98101</dei:EntityAddressPostalZipCode>
    <dei:CityAreaCode
      contextRef="c20261102to20261102"
      id="Fact_ab1c5617f6c54c39b42c5271d55b3afb">206</dei:CityAreaCode>
    <dei:LocalPhoneNumber
      contextRef="c20261102to20261102"
      id="Fact_33ed2a7ed6c944fa846b53e1ac8d5e4a">624-7930</dei:LocalPhoneNumber>
    <dei:WrittenCommunications
      contextRef="c20261102to20261102"
      id="Fact_b726fcbbd7a84858aa913c1460af5d97">false</dei:WrittenCommunications>
    <dei:SolicitingMaterial
      contextRef="c20261102to20261102"
      id="Fact_f599fa56df1c410c9942479d1a5d7b2a">false</dei:SolicitingMaterial>
    <dei:PreCommencementTenderOffer
      contextRef="c20261102to20261102"
      id="Fact_e7df21e988fd4765bb3f4b2e235ccb0d">false</dei:PreCommencementTenderOffer>
    <dei:PreCommencementIssuerTenderOffer
      contextRef="c20261102to20261102"
      id="Fact_4c936bd4bd454f80963a82a7efd5918a">false</dei:PreCommencementIssuerTenderOffer>
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      contextRef="c20261102to20261102_StatementClassOfStockAxis_CommonStockMember"
      id="Fact_d35ce013f74f47a8b807078652ea60f6">Common Stock, $1.00 par value per share</dei:Security12bTitle>
    <dei:TradingSymbol
      contextRef="c20261102to20261102_StatementClassOfStockAxis_CommonStockMember"
      id="Fact_5cb87547505745f68363a769ee26cb67">WAFD</dei:TradingSymbol>
    <dei:SecurityExchangeName
      contextRef="c20261102to20261102_StatementClassOfStockAxis_CommonStockMember"
      id="Fact_8f710e582a2e43bf9afdb3bcf95b2064">NASDAQ</dei:SecurityExchangeName>
    <dei:Security12bTitle
      contextRef="c20261102to20261102_StatementClassOfStockAxis_DepositarySharesEachRepresentingA140thInterestInAShareOf4875FixedRateSeriesMember"
      id="Fact_65be935a2bf64a569e06a3b8a46f16fe">Depositary Shares, Each Representing a 1/40th Interest in a Share of 4.875% Fixed Rate Series A Non-Cumulative Perpetual Preferred Stock</dei:Security12bTitle>
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      contextRef="c20261102to20261102_StatementClassOfStockAxis_DepositarySharesEachRepresentingA140thInterestInAShareOf4875FixedRateSeriesMember"
      id="Fact_211b452afa1845d0b8fb901b6a0545cd">WAFDP</dei:TradingSymbol>
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      id="Fact_936746baa3eb4ab39520788088b4f3e2">NASDAQ</dei:SecurityExchangeName>
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      contextRef="c20261102to20261102"
      id="Fact_ede6ca7c74c240cabf03379cb756f716">false</dei:EntityEmergingGrowthCompany>
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