<SUBMISSION>
<ACCESSION-NUMBER>0001002014-12-000416
<TYPE>4/A
<PUBLIC-DOCUMENT-COUNT>1
<PERIOD>20110504
<FILING-DATE>20120808
<DATE-OF-FILING-DATE-CHANGE>20120808
<REPORTING-OWNER>
<OWNER-DATA>
<CONFORMED-NAME>Weinstein Lawrence A
<CIK>0001498506
</OWNER-DATA>
<FILING-VALUES>
<FORM-TYPE>4/A
<ACT>34
<FILE-NUMBER>000-30414
<FILM-NUMBER>121016039
</FILING-VALUES>
<MAIL-ADDRESS>
<STREET1>13436 BLUE HEON LOOP
<CITY>CHESTERFIELD
<STATE>VA
<ZIP>23838
</MAIL-ADDRESS>
</REPORTING-OWNER>
<ISSUER>
<COMPANY-DATA>
<CONFORMED-NAME>ALR TECHNOLOGIES INC.
<CIK>0001087022
<ASSIGNED-SIC>3669
<IRS-NUMBER>880225807
<STATE-OF-INCORPORATION>NV
<FISCAL-YEAR-END>1231
</COMPANY-DATA>
<BUSINESS-ADDRESS>
<STREET1>7400 BEAUFONT SPRINGS DRIVE
<STREET2>SUITE 300
<CITY>RICHMOND
<STATE>VA
<ZIP>23225
<PHONE>(804) 554-3500
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>7400 BEAUFONT SPRINGS DRIVE
<STREET2>SUITE 300
<CITY>RICHMOND
<STATE>VA
<ZIP>23225
</MAIL-ADDRESS>
<FORMER-COMPANY>
<FORMER-CONFORMED-NAME>ALR TECHNOLOGIES INC
<DATE-CHANGED>19990524
</FORMER-COMPANY>
</ISSUER>
<DOCUMENT>
<TYPE>4/A
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2011-05-04</periodOfReport>

    <dateOfOriginalSubmission>2011-05-06</dateOfOriginalSubmission>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001087022</issuerCik>
        <issuerName>ALR TECHNOLOGIES INC.</issuerName>
        <issuerTradingSymbol>ALRT</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001498506</rptOwnerCik>
            <rptOwnerName>Weinstein Lawrence A</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>13436 BLUE HEON LOOP</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>CHESTERFIELD</rptOwnerCity>
            <rptOwnerState>VA</rptOwnerState>
            <rptOwnerZipCode>23838</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>President</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Options</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>0.07</value>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2011-05-04</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1000000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.07</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2011-05-04</value>
            </exerciseDate>
            <expirationDate>
                <value>2016-05-03</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>1000000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1000000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">On June 27, 2012, the options granted May 4, 2011 to acquire 1,000,000 common shares at $0.20 per share was modified to acquire 1,000,000 common shares at $0.07 per share.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>LAWRENCE WEINSTEIN</signatureName>
        <signatureDate>2012-08-07</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SUBMISSION>
