<SEC-DOCUMENT>0001673985-20-000102.txt : 20200625
<SEC-HEADER>0001673985-20-000102.hdr.sgml : 20200625
<ACCEPTANCE-DATETIME>20200625164558
ACCESSION NUMBER:		0001673985-20-000102
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20200624
FILED AS OF DATE:		20200625
DATE AS OF CHANGE:		20200625

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Karran Todd D.
		CENTRAL INDEX KEY:			0001685376

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-37774
		FILM NUMBER:		20989842

	MAIL ADDRESS:	
		STREET 1:		300 KIMBALL DRIVE, SUITE 101
		STREET 2:		C/O LEGAL DEPT.
		CITY:			PARSIPPANY
		STATE:			NJ
		ZIP:			07054

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			AdvanSix Inc.
		CENTRAL INDEX KEY:			0001673985
		STANDARD INDUSTRIAL CLASSIFICATION:	PLASTICS, MATERIALS, SYNTH RESINS & NONVULCAN ELASTOMERS [2821]
		IRS NUMBER:				812525089
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		300 KIMBALL DRIVE
		STREET 2:		SUITE 101
		CITY:			PARSIPPANY
		STATE:			NJ
		ZIP:			07054
		BUSINESS PHONE:		(973) 526-1800

	MAIL ADDRESS:	
		STREET 1:		300 KIMBALL DRIVE
		STREET 2:		SUITE 101
		CITY:			PARSIPPANY
		STATE:			NJ
		ZIP:			07054
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_159311794140817.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2020-06-24</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001673985</issuerCik>
        <issuerName>AdvanSix Inc.</issuerName>
        <issuerTradingSymbol>ASIX</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001685376</rptOwnerCik>
            <rptOwnerName>Karran Todd D.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>300 KIMBALL DRIVE, SUITE 101</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>PARSIPPANY</rptOwnerCity>
            <rptOwnerState>NJ</rptOwnerState>
            <rptOwnerZipCode>07054</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock, par value $0.01</value>
            </securityTitle>
            <transactionDate>
                <value>2020-06-24</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>8079</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>43254</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Grant of restricted stock units pursuant to the 2016 Stock Incentive Plan of AdvanSix Inc. and its Affiliates, as Amended and Restated, which will vest in full on June 24, 2021.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Achilles B. Kintiroglou for Todd D. Karran</signatureName>
        <signatureDate>2020-06-25</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
