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

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2019-10-25</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001286131</issuerCik>
        <issuerName>STONEMOR PARTNERS LP</issuerName>
        <issuerTradingSymbol>STON</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001650781</rptOwnerCik>
            <rptOwnerName>AXAR CAPITAL MANAGEMENT L.P.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1330 AVENUE OF THE AMERICAS</rptOwnerStreet1>
            <rptOwnerStreet2>30TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10019</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>1</isOther>
            <officerTitle></officerTitle>
            <otherText>See Remarks</otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001673869</rptOwnerCik>
            <rptOwnerName>Axar GP, LLC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1330 AVENUE OF THE AMERICAS, 6TH FLOOR</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10019</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>1</isOther>
            <officerTitle></officerTitle>
            <otherText>See Remarks</otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001673921</rptOwnerCik>
            <rptOwnerName>Axelrod Andrew</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1330 AVENUE OF THE AMERICAS, 6TH FLOOR</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10019</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Series A Preferred Units</value>
            </securityTitle>
            <transactionDate>
                <value>2019-10-25</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1921315</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>1.2</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>37843177</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnotes</value>
                    <footnoteId id="F2"/>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Series A Preferred Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F4"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2019-10-25</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F5"/>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>37843177</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F5"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F4"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F4"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Units</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>37843177</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>37843177</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">1,921,315 Series A Preferred Units were redeemed by the Company in accordance with their terms as set forth in the Issuer's Third Amended and Restated Agreement of Limited Partnership, dated as of June 27, 2019 (the &quot;LPA&quot;). In addition, upon the consummation of the Rights Offering (as defined in the LPA) the remaining Series A Preferred Units became derivative securities as the Series A Preferred Units become convertible into Common Units beginning on the 10th day following the completion of the Rights Offering.</footnote>
        <footnote id="F2">This Form 4 is filed by Axar Capital Management, LP (the &quot;Investment Manager&quot;), Axar GP LLC (&quot;GP&quot;) and Mr. Andrew Axelrod, with respect to the Series A Preferred Units held by certain funds and/or managed accounts (collectively, the &quot;Axar Vehicles&quot;). The Investment Manager serves as the investment manager of the Axar Vehicles. GP is the general partner of Investment Manager. Mr. Andrew Axelrod serves as the sole member of the GP.</footnote>
        <footnote id="F3">Pursuant to Rule 16a-1 under the Securities Exchange Act of 1934, as amended (the &quot;Act&quot;), each of the Reporting Persons may be deemed to be the beneficial owner of the securities reported herein to the extent of his or its pecuniary interest therein, but disclaims beneficial ownership in excess of such amount; and pursuant to Rule 16a-1(a)(4) under the Act, this filing shall not be deemed an admission that any of the Reporting Persons is, for purposes of Section 16 of the Act or otherwise, the beneficial owner of any securities reported herein in excess of such amount.</footnote>
        <footnote id="F4">Each Series A Preferred Unit is convertible into one Common Unit (i) at the option of the holder thereof beginning on the 10th day following the completion of the Rights Offering and (ii) automatically upon the consummation of the C-Corporation Conversion (as defined in the LPA).</footnote>
        <footnote id="F5">Upon the consummation of the Rights Offering, the Series A Preferred Units reported in Table I hereof became derivative securities as the Series A Preferred Units become convertible into Common Units beginning on the 10th day following the completion of the Rights Offering.</footnote>
    </footnotes>

    <remarks>Because Andrew Axelrod serves on the board of directors of the Issuer as a representative of the Reporting Persons, each of the Investment Manager and the GP is a director by deputization.</remarks>

    <ownerSignature>
        <signatureName>AXAR CAPITAL MANAGEMENT, LP, By: Axar GP LLC, its general partner, By:/s/ Andrew Axelrod, its Sole Member</signatureName>
        <signatureDate>2019-10-29</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>AXAR GP LLC, By: /s/ Andrew Axelrod, its Sole Member</signatureName>
        <signatureDate>2019-10-29</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Andrew Axelrod</signatureName>
        <signatureDate>2019-10-29</signatureDate>
    </ownerSignature>
</ownershipDocument>
