WASHINGTON, D.C., July 25, 2005 - Cogent Communications Group, Inc. (AMEX-COI) will host a conference call with financial analysts at 8:30 a.m. (EST) on November 11, 2005 to discuss Cogent's operating results for the third quarter 2005. Cogent will issue a press release announcing the operating results prior to the call on November 11, 2005.

Investors and other interested parties may access a live audio webcast of the earnings call under "Events" at the Investor Relations section of Cogent's website at www.cogentco.com. A replay of the webcast will be available on the website following the earnings call.

On November 14th, Cogent will be hosting its Analyst Conference at its Washington, DC headquarters. Both industry and financial analysts are invited to attend. The senior management team of Cogent will address current and future initiatives and opportunities that exist for Cogent while providing a broad review of recent developments within each department. The event will end with a tour of Cogent's Headquarters including the Network Operations Center and Test Lab. The schedule currently includes presentations by Sales, Marketing, Network Design and Engineering, Construction, Service Provisioning and Finance plus a Senior Executive Q&A that will wrap up the event. Cogent invites all analysts interested in attending to send a request to Cette adresse e-mail est protégée contre les robots spammeurs. Vous devez activer le JavaScript pour la visualiser.. Seating is limited.

About Cogent Communications

Cogent Communications (AMEX: COI) is a multinational, Tier 1 facilities-based ISP recently ranked by Ovum-RHK as the largest provider of Ethernet services in the United States. 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 12 countries and provides IP services in over 85 markets located in North America and Europe.

Since Cogent's inception, Cogent has unleashed the benefits of IP technology, 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 end-to-end control of service delivery and network monitoring.

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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