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

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2020-05-08</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001551152</issuerCik>
        <issuerName>AbbVie Inc.</issuerName>
        <issuerTradingSymbol>ABBV</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001811896</rptOwnerCik>
            <rptOwnerName>Strom Carrie C</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1 N. WAUKEGAN ROAD</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>NORTH CHICAGO</rptOwnerCity>
            <rptOwnerState>IL</rptOwnerState>
            <rptOwnerZipCode>60064</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>SVP &amp; Pres Global Allerg Aesth</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

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                <transactionPricePerShare>
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            <expirationDate>
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            <securityTitle>
                <value>Option (right to buy)</value>
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            <securityTitle>
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            <transactionDate>
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            <transactionAmounts>
                <transactionShares>
                    <value>2017</value>
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                <transactionPricePerShare>
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            <securityTitle>
                <value>Option (right to buy)</value>
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                <transactionShares>
                    <value>2567</value>
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                    <value>0</value>
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                    <value>A</value>
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            <expirationDate>
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                <transactionShares>
                    <value>3440</value>
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                    <value>A</value>
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                <footnoteId id="F5"/>
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            <expirationDate>
                <value>2027-03-06</value>
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                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>3440</value>
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                    <value>D</value>
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        <derivativeTransaction>
            <securityTitle>
                <value>Option (right to buy)</value>
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                <value>2020-05-08</value>
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                <transactionCode>A</transactionCode>
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                <transactionShares>
                    <value>3613</value>
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                <transactionPricePerShare>
                    <value>0</value>
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                    <value>A</value>
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            <exerciseDate>
                <footnoteId id="F6"/>
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            <expirationDate>
                <value>2028-03-06</value>
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                <underlyingSecurityTitle>
                    <value>Common Stock</value>
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                <underlyingSecurityShares>
                    <value>3613</value>
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    </derivativeTable>

    <footnotes>
        <footnote id="F1">Received in exchange for 2,816 shares of Allergan plc common stock in connection with its acquisition by AbbVie Inc. Allergan shareholders received 0.8660 AbbVie shares for each Allergan share (based on the closing price of AbbVie's common stock of $84.22 on May 7, 2020).</footnote>
        <footnote id="F2">Received in exchange for 16,457 restricted stock units of Allergan plc in connection with the acquisition of Allergan plc by AbbVie Inc. and previously issued pursuant to the Amended and Restated 2013 Incentive Award Plan of Allergan plc. The number of AbbVie Inc. restricted stock units was calculated pursuant to an equity award conversion ratio of 2.303. The restricted stock units vest as follows: 5,194 on 12/31/2020; 1,633 on 3/2/2021; 903 on 3/5/2021; 717 on 3/6/2021; 247 on 3/7/2021; 470 on 5/7/2021; 20,844 on 12/31/2021; 1,633 on 3/2/2022; 903 on 3/5/2022; 716 on 3/6/2022; 470 on 5/7/2022; 1,633 on 3/2/2023; 905 on 3/5/2023; and 1,635 on 3/2/2024.</footnote>
        <footnote id="F3">These securities represent restricted stock units granted under the AbbVie 2013 Incentive Stock Program. They vest in four equal annual increments on the date of grant and include the right to have stock withheld for tax purposes. The options are exercisable as follows: 2,579 exercisable as of 5/8/2020 and 861 as of 3/7/2021.</footnote>
        <footnote id="F4">Received in exchange for stock options of Allergan plc in connection with the acquisition of Allergan plc by AbbVie Inc. and previously issued pursuant to the Amended and Restated 2013 Incentive Award Plan of Allergan plc. The number of AbbVie Inc. stock options was calculated pursuant to an equity award conversion ratio of 2.303.</footnote>
        <footnote id="F5">The options are exercisable as follows: 2,579 exercisable as of 5/8/2020 and 861 as of 3/7/2021.</footnote>
        <footnote id="F6">The options are exercisable as follows: 1,804 exercisable as of 5/8/2020; 902 as of 3/6/2021; and 907 as of 3/6/2022.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Steven L. Scrogham, attorney-in-fact for Carrie Strom</signatureName>
        <signatureDate>2020-05-12</signatureDate>
    </ownerSignature>
</ownershipDocument>
