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        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0002065812</identifier>
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        <period>
            <startDate>2025-01-01</startDate>
            <endDate>2025-12-31</endDate>
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    <dei:EntityRegistrantName contextRef="c0" id="ixv-73">FS SPECIALTY LENDING FUND</dei:EntityRegistrantName>
    <ecd:AwardTmgMnpiDiscTextBlock contextRef="c0" id="ixv-1860">&lt;div style="margin-top:12pt; width:456pt; line-height:12pt;font-weight:bold;"&gt; &lt;span style="letter-spacing:-0.2pt;"&gt;Practice and Policies Regarding Personal Trading and Hedging of Fund&#160;Equity&lt;/span&gt;&lt;span style="font-weight:normal;letter-spacing:0.2pt;"&gt; &lt;/span&gt; &lt;/div&gt;&lt;div style="text-indent:20pt; margin-top:8pt; width:456pt; line-height:12pt;"&gt;
          &lt;span style="letter-spacing:0.2pt;"&gt;The Fund has also established a policy designed to prohibit our officers, trustees, and certain employees of the Adviser from purchasing or selling shares of the Fund while in possession of material nonpublic information, or otherwise using such information for their personal benefit or in any manner that would violate applicable laws and regulations. The policy also prohibits all trustees and officers from engaging in hedging or monetization transactions or similar arrangements with respect to the Fund&#x2019;s securities without prior approval of the Fund&#x2019;s chief compliance officer. &lt;/span&gt;
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