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 5, 2015

Sanchez Production Partners LLC

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code: (713) 783-8000

Not Applicable

(Former name or former address, if changed since last report.)

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 5, 2015, the Sanchez Production Partners LLC (the “Company”) entered into that certain First Amendment to Second Amended and Restated Credit Agreement (the “Amendment”) with the guarantors party thereto, the lenders party thereto and Société Générale, as administrative agent and collateral agent. The Amendment amends certain provisions in the Second Amended and Restated Credit Agreement, dated as of May 30, 2015, relating to the change in organizational structure of the Company resulting from the conversion contemplated by the Company’s previously-announced Plan of Conversion. The Amendment will become effective at such time that the Company is converted from a limited liability company to a limited partnership pursuant to the Plan of Conversion considered at the Special Meeting (as described below in Item 5.07).

The foregoing description of the Amendment is qualified in its entirety by the actual Amendment, a copy of which is filed as Exhibit 10.1 to this Form 8-K and incorporated herein by reference.

The Company held its Special Meeting of Unitholders on March 6, 2015 in Houston, Texas (the “Special Meeting”):

A total of 21,981,595 common units of the Company were present at the Special Meeting in person or by proxy, which represented approximately 75% of the outstanding common units of the Company as of February 4, 2015, the record date for the Special Meeting.

Proposal 1: The vote to approve the Plan of Conversion as disclosed in the proxy statement was approved as follows:

Proposal 2: The vote to approve an amendment and restatement of the Constellation Energy Partners LLC 2009 Omnibus Incentive Compensation Plan as the Sanchez Production Partners LP Long-Term Incentive Plan as disclosed in the proxy statement was approved as follows:

In addition to the foregoing, the holder of all of the Company’s outstanding Class A Units and Class Z Unit was present at the Special Meeting in person or by proxy, which represented 100% of each of the outstanding Class A Units and Class Z Unit of the Company as of February 4, 2015, the record date for the Special Meeting. All of the Class A Units and the Class Z Unit were voted “For” each of the proposals set forth above.

(d) Exhibits.

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 hereunto duly authorized.

Exhibit Index