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

    <schemaVersion>X0305</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2012-04-27</periodOfReport>

    <notSubjectToSection16>1</notSubjectToSection16>

    <issuer>
        <issuerCik>0001405287</issuerCik>
        <issuerName>Stream Global Services, Inc.</issuerName>
        <issuerTradingSymbol>SGS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001540906</rptOwnerCik>
            <rptOwnerName>SGS Holdings LLC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>2000 AVENUE OF THE STARS, 12TH FLOOR</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>LOS ANGELES</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>90067</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock, par value $0.001 per share</value>
            </securityTitle>
            <transactionDate>
                <value>2012-04-27</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>521549</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>3.25</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>71532829</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                    <footnoteId id="F3"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock, par value $0.001 per share</value>
            </securityTitle>
            <transactionDate>
                <value>2012-04-27</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>155599</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>3.25</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>71688428</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                    <footnoteId id="F4"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                    <footnoteId id="F4"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock, par value $0.001 per share</value>
            </securityTitle>
            <transactionDate>
                <value>2012-04-27</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>155599</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>3.25</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>71844027</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                    <footnoteId id="F5"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                    <footnoteId id="F5"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock, par value $0.001 per share</value>
            </securityTitle>
            <transactionDate>
                <value>2012-04-27</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1250000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>3.25</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>73094027</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                    <footnoteId id="F6"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                    <footnoteId id="F6"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock, par value $0.001 per share</value>
            </securityTitle>
            <transactionDate>
                <value>2012-04-27</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>2871412</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>3.25</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                    <footnoteId id="F7"/>
                    <footnoteId id="F8"/>
                    <footnoteId id="F9"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                    <footnoteId id="F7"/>
                    <footnoteId id="F8"/>
                    <footnoteId id="F9"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">As of April 27, 2012, each of Ares Corporate Opportunities Fund II, L.P. (&quot;Ares&quot;), EGS Dutchco B.V. (&quot;EGS&quot;), NewBridge International Investment Ltd. (together with Ares and EGS, the &quot;Parent Members&quot;), G. Drew Conway (&quot;Mr. Conway&quot;) and Paul G. Joubert (together with Mr. Conway, the &quot;Rollover Directors&quot;) beneficially owned 50.8%, 19.0%, 28.9%, 0.6% and 0.7%, respectively, of the units of membership interest of SGS Holdings LLC (&quot;Parent&quot;).  Accordingly, each of the Parent Members and the Rollover Directors may be deemed to have indirect beneficial ownership of a portion of the shares of common stock, par value $0.001 per share (&quot;Shares&quot;), of Stream Global Services, Inc. (&quot;Stream&quot;) reported on this Form 4. (continued in footnote 2)</footnote>
        <footnote id="F2">The Parent Members and the Rollover Directors each disclaim beneficial ownership of such Shares except to the extent of their respective pecuniary interests therein, and the inclusion of such Shares in this report shall not be deemed to be an admission of beneficial ownership of such Shares except to the extent of their respective pecuniary interests therein for purposes of Section 16 or any other purpose.</footnote>
        <footnote id="F3">On March 5, 2012, Parent entered into a stock purchase agreement with Lloyd Linnell to acquire 521,549 Shares at a price of $3.25 per Share (the &quot;Linnell Purchase&quot;).  On April 27, 2012, Parent closed the Linnell Purchase and thereby acquired all such Shares.</footnote>
        <footnote id="F4">On March 5, 2012, Parent entered into a stock purchase agreement with Stephen Moore to acquire 155,599 Shares at a price of $3.25 per Share (the &quot;S. Moore Purchase&quot;).  On April 27, 2012, Parent closed the S. Moore Purchase and thereby acquired all such Shares.</footnote>
        <footnote id="F5">On March 5, 2012, Parent entered into a stock purchase agreement with Patricia Moore to acquire 155,599 Shares at a price of $3.25 per Share (the &quot;P. Moore Purchase&quot;).  On April 27, 2012, Parent closed the P. Moore Purchase and thereby acquired all such Shares.</footnote>
        <footnote id="F6">On March 5, 2012, Parent entered into a stock purchase agreement (the &quot;Brookside Stock Purchase Agreement&quot;) with Brookside Capital Trading Fund, L.P. (&quot;Brookside&quot;) to acquire 1,500,000 Shares at a price of $3.25 per Share (the &quot;Brookside Purchase&quot;).  On April 27, 2012, Parent and Brookside entered into an amendment (the &quot;Amendment&quot;) to the Brookside Stock Purchase Agreement reducing the number of Shares to be sold pursuant to the Brookside Stock Purchase Agreement from 1,500,000 Shares to 1,250,000 Shares to reflect the correct number of Shares owned by Brookside.  On April 27, 2012, immediately after entering into the Amendment, Parent closed the Brookside Purchase and thereby acquired all such Shares.</footnote>
        <footnote id="F7">On April 27, 2012, pursuant to the terms of that certain Contribution and Exchange Agreement (the &quot;Parent Contribution Agreement&quot;), dated as of April 27, 2012, by and between Parent and Stream Acquisition, Inc., a Delaware corporation and wholly-owned subsidiary of Parent (&quot;MergerSub&quot;), Parent contributed 73,094,027 Shares to MergerSub in exchange for shares of common stock, par value $0.001 per share of MergerSub.</footnote>
        <footnote id="F8">On April 27, 2012, MergerSub consummated a short-form merger (the &quot;Merger&quot;) under Section 253 of the General Corporation Law of the State of Delaware (&quot;DGCL&quot;) pursuant to which MergerSub merged with and into Stream, with Stream as the surviving corporation (the &quot;Surviving Corporation&quot;).  (continued in footnote 9)</footnote>
        <footnote id="F9">Pursuant to the terms of the Merger, each Share (other than Shares held by Stream as treasury stock, by MergerSub, or by stockholders of Stream who properly exercise statutory appraisal rights under the DGCL) issued and outstanding immediately prior to the effective time of the Merger was cancelled and automatically converted into the right to receive $3.25 in cash, without interest and subject to any applicable withholding tax, upon surrender of the certificate representing such Share, together with a letter of transmittal.  Each Share held by Stream and MergerSub was canceled at the effective time of the Merger for no consideration.  In addition, each share of capital stock of MergerSub issued and outstanding immediately prior to the effective time of the Merger was automatically converted into one share of common stock, par value $0.001 per share, of the Surviving Corporation.  As a result of the Merger, Stream is now owned by Parent, the former sole stockholder of MergerSub.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Nathan Walton, President, for SGS HOLDINGS LLC</signatureName>
        <signatureDate>2012-04-27</signatureDate>
    </ownerSignature>
</ownershipDocument>
