<SUBMISSION>
<ACCESSION-NUMBER>0001179110-18-008728
<TYPE>4
<PUBLIC-DOCUMENT-COUNT>1
<PERIOD>20180614
<FILING-DATE>20180618
<DATE-OF-FILING-DATE-CHANGE>20180618
<REPORTING-OWNER>
<OWNER-DATA>
<CONFORMED-NAME>MISUNAS KATHY
<CIK>0001196486
</OWNER-DATA>
<FILING-VALUES>
<FORM-TYPE>4
<ACT>34
<FILE-NUMBER>001-35155
<FILM-NUMBER>18905825
</FILING-VALUES>
</REPORTING-OWNER>
<ISSUER>
<COMPANY-DATA>
<CONFORMED-NAME>BOINGO WIRELESS INC
<CIK>0001169988
<ASSIGNED-SIC>4899
<IRS-NUMBER>000000000
<STATE-OF-INCORPORATION>DE
<FISCAL-YEAR-END>1231
</COMPANY-DATA>
<BUSINESS-ADDRESS>
<STREET1>10960 WILSHIRE BLVD., 23RD FLOOR
<CITY>LOS ANGELES
<STATE>CA
<ZIP>90024
<PHONE>310-586-5180
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>10960 WILSHIRE BLVD., 23RD FLOOR
<CITY>LOS ANGELES
<STATE>CA
<ZIP>90024
</MAIL-ADDRESS>
</ISSUER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>FORM 4 -
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2018-06-14</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001169988</issuerCik>
        <issuerName>BOINGO WIRELESS INC</issuerName>
        <issuerTradingSymbol>WIFI</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001196486</rptOwnerCik>
            <rptOwnerName>MISUNAS KATHY</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O BOINGO WIRELESS INC.</rptOwnerStreet1>
            <rptOwnerStreet2>10960 WILSHIRE BLVD STE 2300</rptOwnerStreet2>
            <rptOwnerCity>LOS ANGELES</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>90024</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2018-06-14</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>7610</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>22384</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Restricted Stock Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F2"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2018-06-14</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>7610</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F3"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F3"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>7610</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>7611</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The shares acquired represent the vesting of 7610 of the Reporting Person's restricted stock units on June 8, 2018 which were settled on June 14, 2018.</footnote>
        <footnote id="F2">Each Restricted Stock Unit represents a contingent right to receive one share of Boingo Wireless, Inc. common stock.</footnote>
        <footnote id="F3">Subject to continuous service, these Restricted Stock Units shall vest 33 1/3% per year over a three-year period commencing on August 9, 2016, provided, however, that subject to continuous service, these Restricted Stock Units shall vest upon the earlier of (i) a change in control of Boingo Wireless, Inc.; or (ii) the day immediately prior to Boingo Wireless, Inc.'s first regular meeting of stockholders that occurs in 2019. These Restricted Stock Units will be settled in shares of Common Stock that will be delivered to the Reporting Person shortly after each vesting date.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Efren Medina as Attorney-in-Fact for Kathleen Misunas</signatureName>
        <signatureDate>2018-06-18</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SUBMISSION>
