<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0609</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2026-08-19</periodOfReport>

    <issuer>
        <issuerCik>0002046386</issuerCik>
        <issuerName>Medline Inc.</issuerName>
        <issuerTradingSymbol>MDLN</issuerTradingSymbol>
        <issuerForeignTradingSymbol></issuerForeignTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0002061052</rptOwnerCik>
            <rptOwnerName>Boyle James M</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerNonUSAddressFlag>false</rptOwnerNonUSAddressFlag>
            <rptOwnerStreet1>C/O MEDLINE INC.</rptOwnerStreet1>
            <rptOwnerStreet2>3 LAKES DRIVE</rptOwnerStreet2>
            <rptOwnerCity>NORTHFIELD</rptOwnerCity>
            <rptOwnerState>IL</rptOwnerState>
            <rptOwnerZipCode>60093</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>true</isDirector>
            <isOfficer>true</isOfficer>
            <isTenPercentOwner>false</isTenPercentOwner>
            <isOther>false</isOther>
            <officerTitle>Chief Executive Officer</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>false</aff10b5One>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Incentive Units of Medline Holdings, LP</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>16.49</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2026-08-19</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>false</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>764252</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F1"/>
                <footnoteId id="F2"/>
                <footnoteId id="F3"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F1"/>
                <footnoteId id="F2"/>
                <footnoteId id="F3"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Class A Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>764252</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>764252</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnotes</value>
                    <footnoteId id="F2"/>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Represents performance-based incentive units of Medline Holdings, LP (&quot;Incentive Units&quot;), that were earned as a result of the achievement of certain performance criteria as certified by the compensation committee of the Issuer's board of directors on August 19, 2026. These Incentive Units are fully vested.</footnote>
        <footnote id="F2">Incentive Units are &quot;profit interests&quot; having economic characteristics similar to stock appreciation rights. Vested Incentive Units are convertible, at the holder's election, into a number of Common Units generally equal to (a) the product of the number of vested Incentive Units to be converted with a given per unit participation threshold and then-current difference between the per unit value of a Common Unit at the time of the conversion (based on the public trading price of a share of Class A Common Stock) and the per unit participation threshold of such vested Incentive Units divided by (b) the per unit value of a Common Unit at the time of the conversion (based on the public trading price of a share of Class A Common Stock), subject to certain adjustments.</footnote>
        <footnote id="F3">(Continued from Footnote 2 above) Common Units are exchangeable on a one-for-one basis for shares of Class A Common Stock pursuant to the terms of the Exchange Agreement. These Incentive Units have no expiration date. Such Incentive Units are held indirectly through Medline Management Aggregator LLC.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Nicole Fritz, Attorney-in-Fact</signatureName>
        <signatureDate>2026-08-21</signatureDate>
    </ownerSignature>
</ownershipDocument>
