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): November 12, 2012

Summit Midstream Partners, LP

(Exact name of registrant as specified in its charter)

2100 McKinney Avenue

Suite 1250

Dallas, Texas 75201

(Address of principal executive offices) (Zip Code)

Registrants’ telephone number, including area code: (214) 242-1955

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:

o            Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o            Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o            Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o            Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 2.02 Results of Operations and Financial Condition.

On November 12, 2012, Summit Midstream Partners, LP (“SMLP”) announced its results of operations for the quarter ended September 30, 2012. A copy of the press release is attached hereto as Exhibit 99.1.

The information provided pursuant to this Item 2.02, including Exhibit 99.1, is “furnished” and shall not be deemed to be “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of such section, and shall not be incorporated by reference in any filing made by SMLP under the Exchange Act or the Securities Act of 1933, as amended, except to the extent expressly set forth by specific reference in any such filings.

Use of Non-GAAP Financial Measures

In addition to reporting financial results in accordance with U.S. generally accepted accounting principles (“GAAP”), SMLP presents certain non-GAAP financial measures. Specifically, SMLP presents EBITDA, Adjusted EBITDA, distributable cash flow and adjusted distributable cash flow. We define EBITDA as net income, plus interest expense, income tax expense, and depreciation and amortization expense, less interest income and income tax benefit.  We define Adjusted EBITDA as EBITDA plus non-cash compensation expense and adjustments related to MVC shortfall payments.  We define distributable cash flow as Adjusted EBITDA plus cash interest income, less cash paid for interest expense and income taxes and maintenance capital expenditures. We define adjusted distributable cash flow as distributable cash flow plus or minus other non-cash or non-recurring expenses or income.

We exclude these items because they are considered unusual and not indicative of our ongoing operations. Our definitions of these non-GAAP financial measures may differ from the definitions of similar measures used by other companies. Management uses these non-GAAP financial measures in making financial, operating and planning decisions and in evaluating SMLP’s financial performance. Furthermore, management believes that these non-GAAP financial measures may provide users with additional meaningful comparisons between current results and results of prior periods as they are expected to be reflective of our core ongoing business. These measures have limitations, and investors should not consider them in isolation or as a substitute for analysis of SMLP’s results as reported under GAAP.

Reconciliations of GAAP to non-GAAP financial measures are included as attachments to the press release which has been posted in the “Investors” section of our website at http://summitmidstream.com.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits.

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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.

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EXHIBIT INDEX

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