On September 14, 2005, Southwestern Energy Company has entered into an underwriting agreement with RBC Capital Markets Corporation and J.P. Morgan Securities Inc., as the representatives of the several underwriters, with respect to the offering of 8,500,000 shares of its common stock at a price per share to the public of $61.35. Southwestern has granted the underwriters an option to purchase up to 1,275,000 additional shares of common stock to cover over-allotments, if any.  Affiliates of some of the underwriters are lenders under Southwestern's revolving credit facility and, from time to time, the underwriters may provide financial or other advisory services to Southwestern.  The shares are being offered and sold pursuant to a prospectus supplement and accompanying prospectus filed with the Securities and Exchange Commission pursuant to Rule 424(b) of the Securities Act of 1933, as amended, in connection with the company's registration statement on Form S-3 (Registration Statement No. 333-126884), which was declared effective on September 1, 2005.

Southwestern has agreed not to, directly or indirectly,  offer, sell, short sell or otherwise dispose of any shares of its common stock or other securities convertible into or exchangeable or exercisable for shares of its common stock or derivative of its common stock (or agreement for such) will be made for a period of 60 days after the date of the underwriting agreement other than under the underwriting agreement or with the prior written consent of the representatives; provided, that this provision will not restrict the company from issuing common stock pursuant to the exercise of options outstanding on the date of the underwriting agreement, granting employee stock options and restricted stock pursuant to the terms of a plan in effect on the date of the underwriting agreement, issuing common stock pursuant to the exercise of such options, issuances to its employees under the terms of the employee stock purchase plan in effect on the date of the underwriting agreement, issuing common stock pursuant to the terms of the director compensation plan in effect on the date of the underwriting agreement, including its 401(k) plan, the filing of registration statements on Form S-8 and amendments thereto in connection with those stock options or the company’s employee stock purchase plans in existence on the date of the underwriting agreement. In addition, the senior management and the directors of the company have agreed not to sell, option or otherwise dispose of any shares of common stock for a period of 60 days after September 14, 2005 except as permitted under the agreement or with the written consent of the representatives.  

The underwriting agreement also contains standard indemnification rights and obligations of the Company and the underwriters.

The foregoing summary does not purport to be complete and is qualified in its entirety by reference to the underwriting agreement, which is filed as Exhibit 1.1 to this Form 8-K and is incorporated by reference herein.