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

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2008-01-28</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000726603</issuerCik>
        <issuerName>QUESTAR ASSESSMENT, INC.</issuerName>
        <issuerTradingSymbol>QUSA</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001229210</rptOwnerCik>
            <rptOwnerName>BECK MICHAEL D</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>35 GUION STREET</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>PLEASANTVILLE</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10570</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Senior Vice President</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock, par value $.0001 per share</value>
            </securityTitle>
            <transactionDate>
                <value>2008-01-28</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>5200</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>140575</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F2"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Common Stock, Right to Buy</value>
                <footnoteId id="F3"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>4.5</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2008-01-28</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>2500</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F4"/>
            </exerciseDate>
            <expirationDate>
                <value>2018-01-28</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>2500</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2500</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Shares granted as stock bonus pursuant to the 2007 Stock Incentive Plan.</footnote>
        <footnote id="F2">Includes 42,000 shares owned jointly with Mr. Beck's wife.</footnote>
        <footnote id="F3">Granted pursuant to 2007 Stock Incentive Plan.</footnote>
        <footnote id="F4">The options vest in three equal annual installments, commencing January 28, 2009.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Michael D. Beck</signatureName>
        <signatureDate>2008-01-30</signatureDate>
    </ownerSignature>
</ownershipDocument>
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X0202
4
2008-01-28
0
0000726603
QUESTAR ASSESSMENT, INC.
QUSA
0001229210
BECK MICHAEL D
35 GUION STREET
PLEASANTVILLE
NY
10570
1
1
0
0
Senior Vice President
Common Stock, par value $.0001 per share
2008-01-28
4
A
0
5200
0
A
140575
D
Common Stock, Right to Buy
4.5
2008-01-28
4
A
0
2500
0
A
2018-01-28
Common Stock
2500
2500
D
Shares granted as stock bonus pursuant to the 2007 Stock Incentive Plan.
Includes 42,000 shares owned jointly with Mr. Beck's wife.
Granted pursuant to 2007 Stock Incentive Plan.
The options vest in three equal annual installments, commencing January 28, 2009.
Michael D. Beck
2008-01-30