CHICAGO--April 8, 2005--Archipelago Holdings, Inc. (PCX:AX), owner and operator of the Archipelago Exchange(SM) (ArcaEx®), will release its first quarter 2005 results on Monday, April 25, 2005 and will hold a conference call the following day Tuesday, April 26, 2005 at approximately 11:00 am ET to review the results with the investment community.

The call will be webcast live from Archipelago's Investor Relations webpage available at www.archipelago.com and will be accessible by telephone at the following numbers:

Calling from the USA or Canada: 800-884-5695

Calling from other countries: 617-786-2960

Conference ID: 55914470

Results will be available in the Investors Relations section at www.archipelago.com on April 25, 2005. Visitors to www.archipelago.com will be able to listen to an archived copy of the conference call webcast for one month following the call.

About Archipelago

Archipelago Holdings, Inc. (PCX:AX) owns and operates the Archipelago Exchange (ArcaEx). ArcaEx is the first totally open all-electronic stock market in the United States. Through its alliance with the Pacific Exchange, Inc., Archipelago operates ArcaEx as the exclusive equities trading facility of PCX Equities, Inc. Through ArcaEx, Archipelago customers can trade over 8,000 equity securities, including securities listed on the New York Stock Exchange(R), Nasdaq(R), American Stock Exchange(R) and Pacific Exchange(R). ArcaEx is regulated by the Pacific Exchange. The Archipelago ECN, a precursor to ArcaEx, was one of the four original ECNs, formed in December 1996 with Townsend Analytics.

CONTACT: Archipelago Holdings, Inc. Margaret Nagle, 312-442-7083 (Press) Patrick Murphy, 312-442-7005 (Investor Relations)