<?xml version="1.0"?>
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    <periodOfReport>2023-03-10</periodOfReport>

    <notSubjectToSection16>1</notSubjectToSection16>

    <issuer>
        <issuerCik>0001713952</issuerCik>
        <issuerName>Vivint Smart Home, Inc.</issuerName>
        <issuerTradingSymbol>VVNT</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001673823</rptOwnerCik>
            <rptOwnerName>Bywater David</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O VIVINT SMART HOME, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>4931 NORTH 300 WEST</rptOwnerStreet2>
            <rptOwnerCity>PROVO</rptOwnerCity>
            <rptOwnerState>UT</rptOwnerState>
            <rptOwnerZipCode>84604</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chief Executive Officer</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

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                <value>Class A Common Stock</value>
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                <transactionShares>
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                </transactionShares>
                <transactionPricePerShare>
                    <value>12.00</value>
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                <value></value>
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                    <value>428571</value>
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    <footnotes>
        <footnote id="F1">On March 10, 2023, NRG Energy, Inc. (&quot;NRG&quot;) acquired Vivint Smart Home, Inc. (the &quot;Issuer&quot;) pursuant to that certain Agreement and Plan of Merger dated as of December 6, 2022 (the &quot;Merger Agreement&quot;) by and among the Issuer, NRG and Jetson Merger Sub, Inc., a wholly owned subsidiary of NRG (&quot;Merger Sub&quot;). In accordance with the Merger Agreement, Merger Sub merged with and into the Issuer (the &quot;Merger&quot;), with the Issuer surviving the Merger as a wholly owned subsidiary of NRG. At the effective time of the Merger (the &quot;Effective Time&quot;), each issued and outstanding share of Class A common stock, par value $0.0001 per share, of the Issuer (the &quot;Common Stock&quot;) (other than certain excluded shares) automatically converted into the right to receive $12.00 per share in cash, without interest (the &quot;Merger Consideration&quot;).</footnote>
        <footnote id="F2">Each restricted stock unit (&quot;RSU&quot;) represented a contingent right to receive one share of Common Stock. The RSUs were to be settled in either Common Stock or cash.</footnote>
        <footnote id="F3">Pursuant to the Merger Agreement, unvested RSUs of the Issuer were automatically converted into a number of NRG RSUs calculated as the product of (i) the number of shares underlying such Issuer RSU award and (ii) the ratio of the Merger Consideration divided by the average of the closing sales price of NRGs common stock, par value $0.01 per share for the ten (10) consecutive full trading days ending on the trading day immediately preceding the closing date (the &quot;Exchange Ratio&quot;). Such NRG RSUs will continue to be subject to the same terms and conditions (including vesting and termination treatment) as were applicable to the Issuer RSUs.</footnote>
        <footnote id="F4">Reflects an initial grant of 705,216 RSUs. The remaining grant vests in two equal annual installments beginning on June 15, 2023.</footnote>
        <footnote id="F5">Reflects an initial grant of 642,857 RSUs. The remaining grant vests in two equal annual installments beginning on March 1, 2024.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Garner B. Meads, III, as Attorney-in-Fact</signatureName>
        <signatureDate>2023-03-14</signatureDate>
    </ownerSignature>
</ownershipDocument>
