WASHINGTON, D.C., April 11, 2006 - Cogent Communications Group, Inc. (NASDAQ: CCOI) announced today that it has filed a shelf registration statement with the U.S. Securities and Exchange Commission. Upon effectiveness of the shelf registration, Cogent will be able to sell up to $75 million of securities over the next three years. Pursuant to the same shelf registration, certain selling stockholders may sell up to 16 million shares of Cogent common stock they hold over the same period.

After the registration statement is declared effective, Cogent plans to sell approximately 4 million shares of its common stock and the selling stockholders plan to sell 5-7 million shares of common stock (less than 25% of their total holdings) in an underwritten public offering. Dave Schaeffer, Cogent's Chief Executive Officer, said that the offering would serve two purposes. "First, it increases the amount of Cogent's common stock available in the public markets, making the common stock more liquid. Second, it provides additional capital for Cogent to pursue its growth strategies."

A registration statement relating to these securities has been filed with the Securities and Exchange Commission but has not yet become effective. These securities may not be sold nor may offers to buy be accepted prior to the time the registration statement becomes effective. This press release shall not constitute an offer to sell or the solicitation of an offer to buy nor shall there be any sale of these securities in any state in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such state.

This offering will only be made by means of a prospectus. When available, a copy of the prospectus concerning the offering may be obtained from the underwriters.

About Cogent Communications

Cogent Communications (NASDAQ: CCOI) is a multinational Tier 1 facilities-based ISP. Cogent 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 14 countries and provides IP services in over 95 markets located in North America and Europe.

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 This email address is being protected from spambots. You need JavaScript enabled to view it..

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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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