Williams Partners L.P. (NYSE: WPZ) today announced that it has completed a public offering of $600 million of its 4.5 percent senior notes due 2023 at a price of 99.396 percent of par and $400 million of its 5.8 percent senior notes due 2043 at a price of 99.339 percent of par. Williams Partners plans to use the net proceeds from the offering to repay amounts outstanding under the partnership’s commercial paper program, to fund capital expenditures and for general partnership purposes. J.P. Morgan Securities LLC, Morgan Stanley & Co. LLC and RBS Securities Inc. acted as joint book-running managers for the offering. This news release is neither an offer to sell nor a solicitation of an offer to buy any of these securities and shall not constitute an offer, solicitation or sale in any jurisdiction in which such offer, solicitation or sale is unlawful. A copy of the prospectus supplement and related base prospectus may be obtained on the SEC website at www.sec.gov or from any of the underwriters by contacting: J.P. Morgan Securities LLC383 Madison AvenueNew York, NY 10179Attention: Investment Grade Syndicate Desk 3 rd floor Morgan Stanley & Co. LLC1585 BroadwayNew York, NY 10036 RBS Securities Inc.600 Washington BlvdStamford, CT 06901 About Williams Partners L.P. (NYSE: WPZ) Williams Partners L.P. is a leading diversified master limited partnership focused on natural gas transportation; gathering, treating, and processing; storage; natural gas liquid (NGL) fractionation; and oil transportation. The partnership owns interests in three major interstate natural gas pipelines that, combined, deliver 14 percent of the natural gas consumed in the United States. The partnership’s gathering and processing assets include large-scale operations in the U.S. Rocky Mountains and both onshore and offshore along the Gulf of Mexico. Williams (NYSE: WMB) owns approximately 64 percent of Williams Partners, including the general-partner interest.