Stamps.com Unable to Attend ThinkEquity Conference

LOS ANGELES – September 23, 2004 – Stamps.com® (Nasdaq: STMP) announced today that owing to a change of plans it has cancelled its appearance today at the ThinkEquity San Francisco conference. CEO Ken McBride was unable to attend the conference as he was scheduled to be in other meetings for the duration of the week.

Stamps.com also announced today that it is in active discussions with the US Postal Service regarding next steps on the market test of PhotoStamps™. The current market test is expected to end on September 30. Possible outcomes following the current market test include a suspension of the PhotoStamps service while the data from the market test is evaluated, a continuation of the PhotoStamps service while the data from the market test is evaluated, an entirely new market test commencing immediately following the current market test, or a new market test commencing at some future date. Stamps.com expects to announce the next steps for the PhotoStamps service as soon as it is available.

“Safe Harbor” Statement under the Private Securities Litigation Reform Act of 1995: This release may contain forward-looking statements that involve risks and uncertainties. Important factors, including the Company’s ability to complete its products and obtain regulatory approval, which could cause actual results to differ materially from those in the forward-looking statements, are detailed in filings with the Securities and Exchange Commission made from time to time by Stamps.com, including its Annual Report on Form 10-K for the fiscal year ended December 31, 2003, Quarterly Reports on Form 10-Q, and Current Reports on Form 8-K. Stamps.com undertakes no obligation to release publicly any revisions to any forward-looking statements to reflect events or circumstances after the date hereof or to reflect the occurrence of unanticipated events.

Stamps.com, the Stamps.com logo, PhotoStamps, NetStamps and Hidden Postage are trademarks or registered trademarks of Stamps.com Inc. All other brands and names are property of their respective owners.