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  xmlns:dei="http://xbrl.sec.gov/dei/2026"
  xmlns:ffd="http://xbrl.sec.gov/ffd/2026"
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    <link:schemaRef
      xlink:href="https://xbrl.sec.gov/ffd/2026/ffd-2026.xsd"
      xlink:type="simple"/>
    <context id="rc">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001930679</identifier>
        </entity>
        <period>
            <startDate>2026-08-27</startDate>
            <endDate>2026-08-27</endDate>
        </period>
    </context>
    <context id="offrl_1">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001930679</identifier>
            <segment>
                <xbrldi:typedMember dimension="ffd:OfferingAxis">
                    <dei:lineNo>1</dei:lineNo>
                </xbrldi:typedMember>
            </segment>
        </entity>
        <period>
            <startDate>2026-08-27</startDate>
            <endDate>2026-08-27</endDate>
        </period>
    </context>
    <context id="ofst_1">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001930679</identifier>
            <segment>
                <xbrldi:typedMember dimension="ffd:OffsetAxis">
                    <dei:lineNo>1</dei:lineNo>
                </xbrldi:typedMember>
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        </entity>
        <period>
            <startDate>2026-08-27</startDate>
            <endDate>2026-08-27</endDate>
        </period>
    </context>
    <context id="ofst_2">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001930679</identifier>
            <segment>
                <xbrldi:typedMember dimension="ffd:OffsetAxis">
                    <dei:lineNo>2</dei:lineNo>
                </xbrldi:typedMember>
            </segment>
        </entity>
        <period>
            <startDate>2026-08-27</startDate>
            <endDate>2026-08-27</endDate>
        </period>
    </context>
    <unit id="USD">
        <measure>iso4217:USD</measure>
    </unit>
    <unit id="pure">
        <measure>pure</measure>
    </unit>
    <ffd:FormTp contextRef="rc" id="ixv-154">SC TO</ffd:FormTp>
    <ffd:SubmissnTp contextRef="rc" id="ixv-155">SC TO-I</ffd:SubmissnTp>
    <ffd:FeeExhibitTp contextRef="rc" id="ixv-156">EX-FILING FEES</ffd:FeeExhibitTp>
    <dei:EntityCentralIndexKey contextRef="rc" id="ixv-157">0001930679</dei:EntityCentralIndexKey>
    <dei:EntityRegistrantName contextRef="rc" id="ixv-158">KKR FS Income Trust</dei:EntityRegistrantName>
    <ffd:OfferingTableNa contextRef="rc" id="hiddenrcOfferingTableNa" xsi:nil="true"/>
    <ffd:OffsetTableNa contextRef="rc" id="hiddenrcOffsetTableNa" xsi:nil="true"/>
    <ffd:Rule011Flg contextRef="offrl_1" id="ixv-161">true</ffd:Rule011Flg>
    <ffd:OffsetClmdInd contextRef="ofst_1" id="ixv-162">true</ffd:OffsetClmdInd>
    <ffd:OffsetPrrFormTp contextRef="ofst_1" id="hiddenofst_1OffsetPrrFormTp">SC TO</ffd:OffsetPrrFormTp>
    <ffd:OffsetClmdInd contextRef="ofst_2" id="ixv-164">false</ffd:OffsetClmdInd>
    <ffd:OffsetPrrFormTp contextRef="ofst_2" id="hiddenofst_2OffsetPrrFormTp">SC TO</ffd:OffsetPrrFormTp>
    <ffd:PrevslyPdFlg contextRef="offrl_1" id="ixv-208">false</ffd:PrevslyPdFlg>
    <ffd:TxValtn
      contextRef="offrl_1"
      decimals="2"
      id="ixv-209"
      unitRef="USD">83291779.32</ffd:TxValtn>
    <ffd:FeeRate
      contextRef="offrl_1"
      decimals="7"
      id="ixv-210"
      unitRef="pure">0.0001381</ffd:FeeRate>
    <ffd:FeeAmt
      contextRef="offrl_1"
      decimals="2"
      id="ixv-211"
      unitRef="USD">11502.59</ffd:FeeAmt>
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    <ffd:TtlFeeAmt contextRef="rc" decimals="2" id="ixv-213" unitRef="USD">11502.59</ffd:TtlFeeAmt>
    <ffd:TtlPrevslyPdAmt contextRef="rc" decimals="2" id="ixv-214" unitRef="USD">0.00</ffd:TtlPrevslyPdAmt>
    <ffd:TtlOffsetAmt contextRef="rc" decimals="2" id="ixv-215" unitRef="USD">7645.42</ffd:TtlOffsetAmt>
    <ffd:NetFeeAmt contextRef="rc" decimals="2" id="ixv-216" unitRef="USD">3857.17</ffd:NetFeeAmt>
    <ffd:OfferingNote contextRef="offrl_1" id="ixv-217">Calculated as the aggregate maximum purchase price for Class I common shares of beneficial interest, par value $0.01 per share, of KKR FS Income Trust ("Shares"), based upon the net asset value per Share as of July 31, 2026 of $29.08. This amount is based upon the offer to purchase up to 2,864,229 Shares.

Calculated at $138.10 per $1,000,000.00 of the Transaction Valuation in accordance with Rule 0-11 under the Securities Exchange Act of 1934, as amended (the "Exchange Act"), as modified by Filing Fee Rate Advisory for Fiscal Year 2026.

An aggregate fee of $11,380.39 was submitted with the filing of the Schedule TO-I by KKR FS Income Trust on June 1, 2026 (the "June 2026 Schedule TO-I"). The final transaction fee due pursuant to the final amendment to the June 2026 Schedule TO-I filed July 24, 2026 was $3,734.97, as $27,045,371.04 in aggregate value of shares were tendered. Pursuant to Rule 0-11(a)(2) under the Exchange Act, the remaining $7,645.42 portion of the filing fee paid in connection with the September 2025 Schedule TO-I is being used to offset a portion of the filing fee in connection with this Schedule TO-I.</ffd:OfferingNote>
    <ffd:Rule011a2OffsetFlg contextRef="ofst_1" id="ixv-218">true</ffd:Rule011a2OffsetFlg>
    <ffd:OffsetPrrFileNb contextRef="ofst_1" id="ixv-219">005-94079</ffd:OffsetPrrFileNb>
    <ffd:OffsetClmInitlFilgDt contextRef="ofst_1" id="ixv-220">2026-06-01</ffd:OffsetClmInitlFilgDt>
    <ffd:OffsetClmdAmt contextRef="ofst_1" decimals="2" id="ixv-221" unitRef="USD">7645.42</ffd:OffsetClmdAmt>
    <ffd:Rule011a2OffsetFlg contextRef="ofst_2" id="ixv-222">true</ffd:Rule011a2OffsetFlg>
    <ffd:OffsetPrrFilerNm contextRef="ofst_2" id="ixv-223">KKR FS Income Trust</ffd:OffsetPrrFilerNm>
    <ffd:OffsetPrrFileNb contextRef="ofst_2" id="ixv-224">005-94079</ffd:OffsetPrrFileNb>
    <ffd:OffsetSrcFilgDt contextRef="ofst_2" id="ixv-225">2026-06-01</ffd:OffsetSrcFilgDt>
    <ffd:OffsetPrrFeeAmt contextRef="ofst_2" decimals="2" id="ixv-226" unitRef="USD">7645.42</ffd:OffsetPrrFeeAmt>
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