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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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<SEC-DOCUMENT>0001104659-07-063044.txt : 20070816
<SEC-HEADER>0001104659-07-063044.hdr.sgml : 20070816
<ACCEPTANCE-DATETIME>20070816140305
ACCESSION NUMBER:		0001104659-07-063044
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20070814
FILED AS OF DATE:		20070816
DATE AS OF CHANGE:		20070816

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			BreitBurn Energy Partners L.P.
		CENTRAL INDEX KEY:			0001357371
		STANDARD INDUSTRIAL CLASSIFICATION:	CRUDE PETROLEUM & NATURAL GAS [1311]
		IRS NUMBER:				743169953
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		515 SOUTH FLOWER STREET, SUITE 4800
		CITY:			LOS ANGELES
		STATE:			CA
		ZIP:			90071
		BUSINESS PHONE:		(213) 225-5900

	MAIL ADDRESS:	
		STREET 1:		515 SOUTH FLOWER STREET, SUITE 4800
		CITY:			LOS ANGELES
		STATE:			CA
		ZIP:			90071

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			ARMSTRONG GREG L
		CENTRAL INDEX KEY:			0001184537

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33055
		FILM NUMBER:		071062072

	BUSINESS ADDRESS:	
		STREET 1:		333 CLAY ST
		STREET 2:		STE 1600
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77002
		BUSINESS PHONE:		7136464100
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>a4.xml
<DESCRIPTION>4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2007-08-14</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001357371</issuerCik>
        <issuerName>BreitBurn Energy Partners L.P.</issuerName>
        <issuerTradingSymbol>BBEP</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001184537</rptOwnerCik>
            <rptOwnerName>ARMSTRONG GREG L</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>515 SOUTH FLOWER STREET, SUITE 4800</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>LOS ANGELES</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>90071</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Phantom Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2007-08-14</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>69</value>
                    <footnoteId id="F4"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F2"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Units</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>69</value>
                    <footnoteId id="F4"/>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>5626</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Phantom Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2007-08-14</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>53</value>
                    <footnoteId id="F4"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F3"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F3"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Units</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>53</value>
                    <footnoteId id="F4"/>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>4319</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Each Phantom Unit is the economic equivalent of one common unit representing a limited partner interest in BBEP (a &quot;common unit&quot;).</footnote>
        <footnote id="F2">The Phantom Units will be settled for an equal number of common units on October 9, 2009.</footnote>
        <footnote id="F3">The Phantom Units will be settled for an equal number of common units on January 1, 2010.</footnote>
        <footnote id="F4">Represents additional Phantom Units received by the Reporting Person pursuant to the terms of previously granted Distribution Equivalent Rights.  Each Distribution Equivalent Right entitles the Reporting Person to additional Phantom Units with a value equal to the amount of distributions paid on each of BBEP's common units.  On August 14, 2007, BBEP paid a cash distribution to holders of its common units in an amount equal to 42.25 cents per common unit.  Pursuant to the terms of the Distribution Equivalent Rights, the Reporting Person received a number of additional Phantom Units in respect of each Distribution Equivalent Right with a value (based on the closing price of BBEP's common units on the distribution date ($34.07)) equal to the per unit amount of the distribution.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Roberta E. Kass, Attorney-in-Fact</signatureName>
        <signatureDate>2007-08-16</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----