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): May 1, 2006

SOUTHWESTERN ENERGY COMPANY

(Exact name of registrant as specified in its charter)

Arkansas

(State or other jurisdiction of incorporation)

(281) 618-4700

(Registrant's telephone number, including area code)

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))

SECTION 1. Registrant's Business and Operations.

On May 1, 2006, Southwestern Energy Company (the "Company") entered into a stock purchase agreement ("Stock Purchase Agreement") with Atlas Pipeline Partners, L.P. ("Atlas") pursuant to which Atlas would acquire the Company's subsidiary, Mid-Continent Arkansas Pipeline, LLC (formerly Southwestern Energy Pipeline Company) ("MCAP"), which holds a 25% interest in the NOARK Pipeline System, Limited Partnership ("NOARK"), for $69.0 million. Atlas' subsidiary holds the remaining 75% interest in NOARK.  NOARK owns the Ozark Gas Transmission System, which the Company utilizes to transport natural gas.

A copy of the Stock Purchase Agreement was filed as Exhibit 10.1 to the Company's Current Report on Form 8-K dated May 4, 2006, and is incorporated herein by reference.