UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

PURSUANT TO SECTION 13 OR 15(d)

OF THE SECURITIES EXCHANGE ACT OF 1934

Date of Report (Date of earliest event reported): March 16, 2015 (March 11, 2015)

SUNOCO LOGISTICS PARTNERS L.P.

(Exact name of registrant as specified in its charter)

1818 Market Street, Suite 1500, Philadelphia, PA 19103-3615

(Address of principal executive office) (Zip Code)

(866) 248-4344

(Registrants’ telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

On March 11, 2015, Sunoco Logistics Partners L.P. (the “Partnership”) entered into an underwriting agreement (the “Underwriting Agreement”) with Morgan Stanley & Co. LLC, Barclays Capital Inc., Merrill Lynch, Pierce, Fenner & Smith Incorporated, UBS Securities LLC, Wells Fargo Securities, LLC, J.P. Morgan Securities LLC, Goldman, Sachs & Co., Credit Suisse Securities (USA) LLC, RBC Capital Markets, LLC, and Jefferies LLC, as representatives of the several underwriters named in the Underwriting Agreement (the “Underwriters”).

The Underwriting Agreement provides for the issuance and sale by the Partnership of 13,500,000 common units representing limited partner interests in the Partnership (“Common Units”) in an underwritten public offering (the “Offering”) at a price to the public of $41.76 per Common Unit. The Partnership has also granted the Underwriters a 30-day option to purchase up to 2,025,000 additional Common Units. The Common Units to be issued pursuant to the Underwriting Agreement were registered under the Securities Act of 1933, as amended, pursuant to an effective shelf registration statement on Form S-3 (File No. 333-185192).

Affiliates of certain of the Underwriters are lenders under the Partnership’s $1.5 billion revolving credit facility and, accordingly, will receive a portion of the net proceeds of the Offering through the Partnership’s repayment of borrowings under such facility.

The closing of the Offering occurred on March 16, 2015. A copy of the Underwriting Agreement is filed as Exhibit 1.1 to this Current Report on Form 8-K and is incorporated herein by reference.

(d) Exhibits

1

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

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