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

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2019-03-19</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000100493</issuerCik>
        <issuerName>TYSON FOODS, INC.</issuerName>
        <issuerTradingSymbol>TSN</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001721646</rptOwnerCik>
            <rptOwnerName>Whitmore Justin</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>2200 W DON TYSON PARKWAY</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>SPRINGDALE</rptOwnerCity>
            <rptOwnerState>AR</rptOwnerState>
            <rptOwnerZipCode>72762</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>EVP Cont Impr &amp; CSO</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class A Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2019-03-19</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>110.303</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>10994.966</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class A Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2019-05-10</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F3"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>2242.827</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>79.81</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>13237.793</value>
                    <footnoteId id="F4"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Represents shares of the Issuer's Class A Common Stock received by the Reporting Person pursuant to the Issuer's dividend reinvestment plan since the last Statement of Changes in Beneficial Ownership was filed by the Reporting Person.  Such acquisitions are exempt from Section 16 concurrent reporting requirements pursuant to Rule 16a-11.</footnote>
        <footnote id="F2">Includes 4,424.701 shares of Class A Common Stock which vest on May 12, 2020 if the Reporting Person is employed by the Issuer on the vesting date and 2,310.543 shares which vest on November 13, 2020 if the performance metric described in the applicable Stock Incentive Agreement (&quot;SIA&quot;) is achieved and the Reporting Person is employed by the Issuer on the vesting date; and 4,259.722 shares of Class A Common Stock which vest on November 29, 2021 if the performance metric described in the applicable SIA is achieved.</footnote>
        <footnote id="F3">Award of Class A Common Stock which vests on May 10, 2022 if the performance metric described in the applicable SIA is achieved. The performance metric is the achievement of a target cumulative adjusted operating income from March 31, 2019 to October 2, 2021 as set forth in the SIA. If the performance metric is not achieved, the award expires.</footnote>
        <footnote id="F4">Includes 4,424.701 shares of Class A Common Stock which vest on May 12, 2020 if the Reporting Person is employed by the Issuer on the vesting date and 2,310.543 shares which vest on November 13, 2020 if the performance metric described in the applicable SIA is achieved and the Reporting Person is employed by the Issuer on the vesting date; 4,259.722 shares of Class A Common Stock which vest on November 29, 2021 if the performance metric described in the applicable SIA is achieved and 2,242.827 shares of Class A Common Stock which vest on May 10, 2022 if the performance metric described in the applicable SIA is achieved.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ R. Read Hudson by Power of Attorney for Justin Whitmore</signatureName>
        <signatureDate>2019-05-13</signatureDate>
    </ownerSignature>
</ownershipDocument>
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X0306
4
2019-03-19
0
0000100493
TYSON FOODS, INC.
TSN
0001721646
Whitmore Justin
2200 W DON TYSON PARKWAY
SPRINGDALE
AR
72762
0
1
0
0
EVP Cont Impr & CSO
Class A Common Stock
2019-03-19
4
J
0
110.303
0
A
10994.966
D
Class A Common Stock
2019-05-10
4
A
0
2242.827
79.81
A
13237.793
D
Represents shares of the Issuer's Class A Common Stock received by the Reporting Person pursuant to the Issuer's dividend reinvestment plan since the last Statement of Changes in Beneficial Ownership was filed by the Reporting Person.  Such acquisitions are exempt from Section 16 concurrent reporting requirements pursuant to Rule 16a-11.
Includes 4,424.701 shares of Class A Common Stock which vest on May 12, 2020 if the Reporting Person is employed by the Issuer on the vesting date and 2,310.543 shares which vest on November 13, 2020 if the performance metric described in the applicable Stock Incentive Agreement ("SIA") is achieved and the Reporting Person is employed by the Issuer on the vesting date; and 4,259.722 shares of Class A Common Stock which vest on November 29, 2021 if the performance metric described in the applicable SIA is achieved.
Award of Class A Common Stock which vests on May 10, 2022 if the performance metric described in the applicable SIA is achieved. The performance metric is the achievement of a target cumulative adjusted operating income from March 31, 2019 to October 2, 2021 as set forth in the SIA. If the performance metric is not achieved, the award expires.
Includes 4,424.701 shares of Class A Common Stock which vest on May 12, 2020 if the Reporting Person is employed by the Issuer on the vesting date and 2,310.543 shares which vest on November 13, 2020 if the performance metric described in the applicable SIA is achieved and the Reporting Person is employed by the Issuer on the vesting date; 4,259.722 shares of Class A Common Stock which vest on November 29, 2021 if the performance metric described in the applicable SIA is achieved and 2,242.827 shares of Class A Common Stock which vest on May 10, 2022 if the performance metric described in the applicable SIA is achieved.
/s/ R. Read Hudson by Power of Attorney for Justin Whitmore
2019-05-13