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

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2016-05-27</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001506401</issuerCik>
        <issuerName>InfraREIT, Inc.</issuerName>
        <issuerTradingSymbol>HIFR</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001631043</rptOwnerCik>
            <rptOwnerName>Phillips Lance</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1807 ROSS AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2>4TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>DALLAS</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>75201</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>VP, Prin. Acct. Ofc. &amp; Cont.</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>common stock, $0.01 par value per share</value>
            </securityTitle>
            <transactionDate>
                <value>2016-05-27</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1250</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1668</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeHolding>
            <securityTitle>
                <value>common units</value>
                <footnoteId id="F3"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F3"/>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F3"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F3"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>common stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>21385</value>
                    <footnoteId id="F2"/>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>21385</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                    <footnoteId id="F4"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Electricity Participant Partnership, LLC</value>
                    <footnoteId id="F4"/>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeHolding>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Represents the receipt of a grant of common stock by Mr. Phillips from Hunt Transmission Services, LLC, a subsidiary of Hunt Consolidated, Inc. (&quot;HCI&quot;), as incentive compensation. The stock is restricted and subject to vesting. The shares will vest one-third on January 1, 2017, one-third on January 1, 2018 and the balance of shares will vest on January 1, 2019, subject to continual service by Mr. Phillips with HCI or an affiliate thereof on such dates.</footnote>
        <footnote id="F2">In the aggregate, Mr. Phillips beneficially owns 23,053 shares of common stock, consisting of the 1,668 shares of common stock shown in Table I and the 21,385 shares underlying the common units shown in Table II.</footnote>
        <footnote id="F3">Represents common units of InfraREIT Partners, LP. Pursuant to the Third Amended and Restated Agreement of Limited Partnership of InfraREIT Partners, LP, common units are redeemable for cash or, at InfraREIT, Inc.'s election, shares of InfraREIT, Inc.'s common stock on a one-for-one basis.  The right to redeem common units does not have an expiration date.</footnote>
        <footnote id="F4">The 21,385 common units beneficially owned by Mr. Phillips are held by Electricity Participant Partnership, LLC, a subsidiary of HCI.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Gregory S. Imhoff, as Attorney-In-Fact for Lance J. Phillips</signatureName>
        <signatureDate>2016-05-31</signatureDate>
    </ownerSignature>
</ownershipDocument>
