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            <identifier scheme="http://www.sec.gov/CIK">0002051820</identifier>
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        <period>
            <startDate>2025-01-01</startDate>
            <endDate>2025-12-31</endDate>
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    <dei:DocumentType contextRef="P01_01_2025To12_31_2025" id="hidden163728359">DEF 14A</dei:DocumentType>
    <dei:AmendmentFlag contextRef="P01_01_2025To12_31_2025" id="ixv-2719">false</dei:AmendmentFlag>
    <dei:EntityCentralIndexKey contextRef="P01_01_2025To12_31_2025" id="ixv-2720">0002051820</dei:EntityCentralIndexKey>
    <dei:EntityRegistrantName contextRef="P01_01_2025To12_31_2025" id="ixv-2730">MOUNT LOGAN CAPITAL INC.</dei:EntityRegistrantName>
    <ecd:InsiderTrdPoliciesProcAdoptedFlag contextRef="P01_01_2025To12_31_2025" id="ixv-2734">true</ecd:InsiderTrdPoliciesProcAdoptedFlag>
    <ecd:AwardTmgMnpiDiscTextBlock contextRef="P01_01_2025To12_31_2025" id="ixv-1481">&lt;div style="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman;font-weight:bold"&gt;Grant of Certain Equity Awards Close in Time to the Release of Material Nonpublic Information &lt;/div&gt;&lt;div style="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman"&gt;Neither Legacy Mount Logan nor Mount Logan granted awards of stock options, stock appreciation rights or similar option-like instruments during 2025. Accordingly, there is nothing to report under Item 402(x) of Regulation &lt;div style="white-space: nowrap; letter-spacing: 0px; top: 0px;display:inline;"&gt;S-K.&lt;/div&gt; &lt;/div&gt;</ecd:AwardTmgMnpiDiscTextBlock>
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