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

    <schemaVersion>X0508</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2025-07-15</periodOfReport>

    <issuer>
        <issuerCik>0001412408</issuerCik>
        <issuerName>Phreesia, Inc.</issuerName>
        <issuerTradingSymbol>PHR</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001776729</rptOwnerCik>
            <rptOwnerName>Linetsky David</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O PHREESIA</rptOwnerStreet1>
            <rptOwnerStreet2>1521 CONCORD PIKE, SUITE 301 PMB 221</rptOwnerStreet2>
            <rptOwnerCity>WILMINGTON</rptOwnerCity>
            <rptOwnerState>DE</rptOwnerState>
            <rptOwnerZipCode>19803</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isOfficer>1</isOfficer>
            <officerTitle>President, Network Solutions</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2025-07-15</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1500</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>26.73</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>11175</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Spouse</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>224056</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The shares reported in this transaction represent restricted stock units (&quot;RSUs&quot;) issued to the Reporting Person's spouse under the Phreesia, Inc. 2019 Stock Option and Incentive Plan. Each RSU represents the contingent right to receive one share of the Issuer's common stock. The RSUs vest as follows: 10% of the RSUs shall vest on July 15, 2026, 20% of the RSUs shall vest on July 15, 2027, 30% of the RSUs shall vest on July 15, 2028 and 40% of the RSUs shall vest on July 15, 2029, subject to the Reporting Person's continued service to the Issuer through each vesting date.</footnote>
        <footnote id="F2">The total in Column 5 has been adjusted to correct an understatement of direct holdings by 114 shares and an overstatement of indirect holdings by 114 shares, first reflected in a Form 4 filed September 18, 2025. A sale of 114 shares by the Reporting Person's spouse on September 16, 2025 was timely reported but inadvertently reported the form of ownership as direct rather than indirect.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Allison Hoffman by Power of Attorney for David Linetsky</signatureName>
        <signatureDate>2026-02-17</signatureDate>
    </ownerSignature>
</ownershipDocument>
