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

    <schemaVersion>X0609</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2026-04-08</periodOfReport>

    <issuer>
        <issuerCik>0001766502</issuerCik>
        <issuerName>Chewy, Inc.</issuerName>
        <issuerTradingSymbol>CHWY</issuerTradingSymbol>
        <issuerForeignTradingSymbol></issuerForeignTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001879000</rptOwnerCik>
            <rptOwnerName>Billings William G.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerNonUSAddressFlag>false</rptOwnerNonUSAddressFlag>
            <rptOwnerStreet1>7700 WEST SUNRISE BOULEVARD</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>PLANTATION</rptOwnerCity>
            <rptOwnerState>FL</rptOwnerState>
            <rptOwnerZipCode>33322</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isOfficer>1</isOfficer>
            <officerTitle>Chief Accounting Officer</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class A Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2026-04-08</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>32571</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>32571</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Class A Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>14470</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Class A Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>36338</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Class A Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>43750</value>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Class A Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>27026</value>
                    <footnoteId id="F4"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Class A Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>19033</value>
                    <footnoteId id="F5"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Represents restricted stock units (&quot;RSUs&quot;) granted to the filing person on April 8, 2026. Each RSU represents a contingent right to receive one share of Class A common stock of Chewy, Inc. The RSUs are subject to time-vesting conditions. 25% of these RSUs will vest on March 1, 2027, and 6.25% will vest on each three-month anniversary thereafter, subject to the filing person's continued employment with Chewy, Inc. through the applicable vesting date.</footnote>
        <footnote id="F2">Represents performance-based restricted stock units (&quot;PRSUs&quot;) granted to the filing person. Each PRSU represents a contingent right to receive one share of Class A common stock of Chewy, Inc. The PRSUs were initially granted on April 8, 2025 and the amount of PRSUs eligible for vesting was subject to certification of the satisfaction of certain performance conditions for the 2025 fiscal year by the Compensation Committee of the Board of Directors. On March 5, 2026, the Compensation Committee of the Board of Directors certified the achievement of the performance conditions for the PRSUs, which vest on March 1, 2028, subject to the filing person's continued employment with Chewy, Inc. through the vesting date.</footnote>
        <footnote id="F3">Represents RSUs granted to the filing person on September 20, 2024. Each RSU represents a contingent right to receive one share of Class A common stock of Chewy, Inc. The RSUs are subject to time-vesting conditions. 58.5% will vest on August 1, 2026, and 41.5% will vest on August 1, 2027, subject to the filing person's continued employment with Chewy, Inc. through the applicable vesting date.</footnote>
        <footnote id="F4">Represents RSUs granted to the filing person on September 20, 2024. Each RSU represents a contingent right to receive one share of Class A common stock of Chewy, Inc. The RSUs are subject to time-vesting conditions. 10% will vest on May 1, 2026, and each three-month anniversary thereafter, subject to the filing person's continued employment with Chewy, Inc. through the applicable vesting date.</footnote>
        <footnote id="F5">Represents RSUs granted to the filing person on April 8, 2025. Each RSU represents a contingent right to receive one share of Class A common stock of Chewy, Inc. The RSUs are subject to time-vesting conditions. 8.33% will vest on June 1, 2026 and on each three-month anniversary thereafter, subject to the filing person's continued employment with Chewy, Inc. through the applicable vesting date.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Da-Wai Hu, as Attorney-in-fact- for William G. Billings</signatureName>
        <signatureDate>2026-04-10</signatureDate>
    </ownerSignature>
</ownershipDocument>
