<SEC-DOCUMENT>0001979234-26-000001.txt : 20260127
<SEC-HEADER>0001979234-26-000001.hdr.sgml : 20260127
<ACCEPTANCE-DATETIME>20260127113900
ACCESSION NUMBER:		0001979234-26-000001
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20260123
FILED AS OF DATE:		20260127
DATE AS OF CHANGE:		20260127

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Kalman Hirschfeld Tatiana
		CENTRAL INDEX KEY:			0001979234
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-40718
		FILM NUMBER:		26563287

	MAIL ADDRESS:	
		STREET 1:		C/O SYLVAMO CORPORATION
		STREET 2:		6077 PRIMACY PARKWAY
		CITY:			MEMPHIS
		STATE:			TN
		ZIP:			38119

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Sylvamo Corp
		CENTRAL INDEX KEY:			0001856485
		STANDARD INDUSTRIAL CLASSIFICATION:	PAPER MILLS [2621]
		ORGANIZATION NAME:           	04 Manufacturing
		EIN:				862596371
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		6077 PRIMACY PARKWAY
		CITY:			MEMPHIS
		STATE:			TN
		ZIP:			38119
		BUSINESS PHONE:		901-519-8000

	MAIL ADDRESS:	
		STREET 1:		6077 PRIMACY PARKWAY
		CITY:			MEMPHIS
		STATE:			TN
		ZIP:			38119
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primarydocument.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0508</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2026-01-23</periodOfReport>

    <notSubjectToSection16>false</notSubjectToSection16>

    <issuer>
        <issuerCik>0001856485</issuerCik>
        <issuerName>Sylvamo Corp</issuerName>
        <issuerTradingSymbol>SLVM</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001979234</rptOwnerCik>
            <rptOwnerName>Kalman Hirschfeld Tatiana</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O SYLVAMO CORPORATION</rptOwnerStreet1>
            <rptOwnerStreet2>6077 PRIMACY PARKWAY</rptOwnerStreet2>
            <rptOwnerCity>MEMPHIS</rptOwnerCity>
            <rptOwnerState>TN</rptOwnerState>
            <rptOwnerZipCode>38119</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>false</isDirector>
            <isOfficer>true</isOfficer>
            <isTenPercentOwner>false</isTenPercentOwner>
            <isOther>false</isOther>
            <officerTitle>SVP &amp; GM, Latin America</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>false</aff10b5One>

    <nonDerivativeTable></nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Dividend Equivalent Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2026-01-23</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>false</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>142.4453</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>51.05</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F1"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>142.4453</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>924.5368</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Consists of dividend equivalent units (&quot;DEUs&quot;) accrued on restricted stock units (&quot;RSUs&quot;) previously granted to the Reporting Person. The DEUs will vest and be settled on the same terms and conditions as the original RSUs to which they relate. Each DEU represents the right to receive, subject to vesting, one share of Sylvamo Corporation common stock. The number of DEUs has been rounded to 4 decimal points.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Maria St. John Daugherty, attorney in fact for Tatiana Kalman Hirschfeld</signatureName>
        <signatureDate>2026-01-27</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
