<SEC-DOCUMENT>0001209191-21-028419.txt : 20210426
<SEC-HEADER>0001209191-21-028419.hdr.sgml : 20210426
<ACCEPTANCE-DATETIME>20210426200623
ACCESSION NUMBER:		0001209191-21-028419
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20210422
FILED AS OF DATE:		20210426
DATE AS OF CHANGE:		20210426

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Buick Mike
		CENTRAL INDEX KEY:			0001730712

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-34198
		FILM NUMBER:		21855528

	MAIL ADDRESS:	
		STREET 1:		7301 OHMS LANE SUITE 600
		CITY:			EDINA
		STATE:			MN
		ZIP:			55439

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			SunOpta Inc.
		CENTRAL INDEX KEY:			0000351834
		STANDARD INDUSTRIAL CLASSIFICATION:	WHOLESALE-FARM PRODUCT RAW MATERIALS [5150]
		IRS NUMBER:				000000000
		STATE OF INCORPORATION:			Z4
		FISCAL YEAR END:			0102

	BUSINESS ADDRESS:	
		STREET 1:		2233 ARGENTIA ROAD
		STREET 2:		SUITE 401
		CITY:			MISSISSAUGA
		STATE:			A6
		ZIP:			L5N 2X7
		BUSINESS PHONE:		(905) 455-1990

	MAIL ADDRESS:	
		STREET 1:		2233 ARGENTIA ROAD
		STREET 2:		SUITE 401
		CITY:			MISSISSAUGA
		STATE:			A6
		ZIP:			L5N 2X7

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	SUNOPTA INC
		DATE OF NAME CHANGE:	20031107

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	STAKE TECHNOLOGY LTD
		DATE OF NAME CHANGE:	19940901
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc4.xml
<DESCRIPTION>FORM 4 SUBMISSION
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2021-04-22</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000351834</issuerCik>
        <issuerName>SunOpta Inc.</issuerName>
        <issuerTradingSymbol>STKL</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001730712</rptOwnerCik>
            <rptOwnerName>Buick Mike</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>7301 OHMS LANE SUITE 600</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>EDINA</rptOwnerCity>
            <rptOwnerState>MN</rptOwnerState>
            <rptOwnerZipCode>55439</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>SVP and GM</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Performance Stock Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2021-04-22</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>76782</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2021-04-22</value>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F2"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Shares</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>76782</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Each Performance Stock Unit represents a contingent right to receive one share of STKL common stock.</footnote>
        <footnote id="F2">The Performance Stock Units do not have an expiration date.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Jill Barnett, attorney-in-fact</signatureName>
        <signatureDate>2021-04-26</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
