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): February 27, 2003 ----------------- NORTHWEST PIPELINE CORPORATION (Exact name of registrant as specified in its charter) <Table> DELAWARE 1-7414 87-0269236 (State or other jurisdiction (Commission File Number) (I.R.S. Employer of incorporation) Identification No.) 295 CHIPETA WAY 84108 SALT LAKE CITY, UTAH (Zip Code) (Address of principal executive offices) </Table> Registrant's telephone number, including area code: 801-583-8800 NOT APPLICABLE (Former name or former address, if changed since last report) ITEM 9. REGULATION FD DISCLOSURE Northwest Pipeline Corporation wishes to disclose for Regulation FD purposes its press release dated February 27, 2003, as set forth in Exhibit 99 attached hereto. SIGNATURE 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. NORTHWEST PIPELINE CORPORATION By: /s/ Brian K. Shore ------------------------------ Name: Brian K. Shore Title: Corporate Secretary Dated: February 28, 2003 2 INDEX TO EXHIBITS <Table> <Caption> EXHIBIT NUMBER DESCRIPTION - ------- ----------- 99 Copy of Northwest Pipeline Corporation's press release dated February 27, 2003. </Table> 3