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

    <schemaVersion>X0306</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2022-01-28</periodOfReport>

    <dateOfOriginalSubmission>2022-02-01</dateOfOriginalSubmission>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001805833</issuerCik>
        <issuerName>System1, Inc.</issuerName>
        <issuerTradingSymbol>SST</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001845026</rptOwnerCik>
            <rptOwnerName>Kazerani Moujan</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O SYSTEM1, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>4235 REDWOOD AVENUE</rptOwnerStreet2>
            <rptOwnerCity>MARINA DEL REY</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>90066</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class A Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2022-01-28</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>20500</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>10.31</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>20500</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Spouse</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Warrants (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F2"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2022-01-28</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>40700</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>1.02</value>
                    <footnoteId id="F3"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F2"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Class A Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>40700</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>40700</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Spouse</value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Represents the weighted average purchase price paid. These shares were purchased in multiple transactions at prices ranging from $9.96 to $10.59, inclusive. The reporting person undertakes to provide to System1, Inc. (the &quot;Company&quot;), any securityholder of the Company, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth in this footnote to this Form 4.</footnote>
        <footnote id="F2">Each warrant entitles the holder thereof to purchase one share of Class A common stock of System1, Inc. (the &quot;Company&quot;) at an exercise price of $11.50 per share. The warrants become exercisable 30 days after the completion of the Business Combination. The warrants expire five years after the completion of the Business Combination or earlier upon redemption or liquidation, as described under the heading &quot;Description of System1 Securities-System1 Warrants&quot; in the Company's registration statement on Form S-4 (File No. 333-260714).</footnote>
        <footnote id="F3">Represents the weighted average purchase price paid. These warrants were purchased in multiple transactions at prices ranging from $1.00 to $1.06, inclusive. The reporting person undertakes to provide to the Company, any securityholder of the Company, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of warrants purchased at each separate price within the ranges set forth in this footnote to this Form 4.</footnote>
    </footnotes>

    <remarks>This Form 4/A restates in its entirety the Form 4 filed on February 1, 2022, (the &quot;Original Form 4&quot;), which mistakenly reported that the reporting person beneficially owned 75,612 shares of Class A common stock held by Carbon Investments, LLC. The Original Form 4 also excluded the reporting person's indirect acquisitions of 20,500 shares of Class A common stock and 40,700 warrants by the spouse of Ms. Kazerani.</remarks>

    <ownerSignature>
        <signatureName>By: /s/ Daniel Weinrot, Attorney-in-Fact for Moujan Kazerani</signatureName>
        <signatureDate>2022-03-07</signatureDate>
    </ownerSignature>
</ownershipDocument>
