WASHINGTON, D.C., March 22, 2005 - Cogent Communications Group, Inc. (AMEX: COI), a leading facilities-based provider of low-cost, high speed Internet access and Internet Protocol Communications services, has announced that its previously announced 1-for-20 reverse stock split of all outstanding shares of the company's common stock will be effected as of the start of trading on March 24, 2005. At that time each previously outstanding 20 shares of common stock will be combined into 1 share of common stock. No fractional shares will be issued and stockholders will receive cash in lieu of fractional shares. After the reverse stock split the company will have approximately 32.4 million outstanding shares of its common stock. At market close on March 22, 2005 Cogent's common stock price was $.65 per share and approximately 648 million common shares were outstanding yielding a market capitalization of $421 million.

About Cogent Communications

Cogent Communications (AMEX: COI) is a multinational, Tier 1 facilities-based ISP that specializes in providing businesses with high speed Internet access and point-to-point transport services. Cogent's facilities-based, all-optical IP network backbone spans 11 countries and provides IP services in markets located in North America and Europe.

Since Cogent's inception, Cogent has exploited the benefits that IP technology provides, building one of the largest and highest capacity IP networks in existence. This network enables Cogent to offer large bandwidth connections at highly competitive prices. Network ownership also enables Cogent to offer superior customer support through the ability to control service delivery and network monitoring end-to-end.

Cogent Communications is headquartered at 1015 31st Street, NW, Washington, D.C. 20007. For more information, visit www.cogentco.com. Cogent Communications can be reached in the United States at (202) 295-4200 or via email at Cette adresse e-mail est protégée contre les robots spammeurs. Vous devez activer le JavaScript pour la visualiser..

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Information in this release may involve expectations, beliefs, plans, intentions or strategies regarding the future. These forward-looking statements involve risks and uncertainties. All forward-looking statements included in this release are based upon information available to Cogent Communications Group, Inc. as of the date of the release, and we assume no obligation to update any such forward-looking statement. The statements in this release are not guarantees of future performance and actual results could differ materially from our current expectations. Numerous factors could cause or contribute to such differences. Some of the factors and risks associated with our business are discussed in Cogent's registration statements filed with the Securities and Exchange Commission and in its other reports filed from time to time with the SEC.

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