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    <periodOfReport>2012-09-06</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000741516</issuerCik>
        <issuerName>AMERICAN NATIONAL BANKSHARES INC.</issuerName>
        <issuerTradingSymbol>amnb</issuerTradingSymbol>
    </issuer>

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            <rptOwnerName>HALEY MICHAEL P</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>628 MAIN STREET</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>DANVILLE</rptOwnerCity>
            <rptOwnerState>VA</rptOwnerState>
            <rptOwnerZipCode>24541</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Deferred stock issuance</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Carolyn Compton</signatureName>
        <signatureDate>2017-03-28</signatureDate>
    </ownerSignature>
</ownershipDocument>
