WASHINGTON, D.C., July 20, 2005 - Cogent Communications Group, Inc. (AMEX: COI), a multinational Tier 1 Internet service provider, announced today that it is making a unique offer to cable companies interested in testing Cogent's high quality Internet service without the risk of a long term commitment other providers require. Recently ranked as the largest Ethernet service provider in the United States, Cogent's new "Zero Commit" offer will help cable companies improve margins in their consumer broadband access businesses. Cogent's "Zero Commit" program allows the cable customer to cancel service within thirty (30) days of service initiation for any reason. The cable customer will pay only for the full first month of service charges but will be credited back any installation charges already paid.

"Thanks to Cogent's low cost structure and all-IP network architecture, you can have it both ways – low cost and high quality. Current Cogent customers enjoy this today. They tell us overwhelmingly that our price, network performance, and customer service are the attributes they most value from Cogent, " said Reed Harrison, President and Chief Operating Officer. "We want to make it as easy as we possibly can for new customers to have the opportunity to 'test drive' Cogent's price/performance."

"We see a huge opportunity in the consumer broadband market as bandwidth demands in the home explode over the next decade," said Dave Schaeffer, CEO of Cogent Communications. "Unlike many service providers, Cogent does not compete in the consumer market, but remains focused on the enterprise market and the core of the internet – segments in which Cogent dominates as a price leader."

Cogent is eager to extend this offer based on a pattern of success this type of program has had in the past. Just 2 years ago, Cogent noticed a similar pattern of bandwidth growth among students and offered a comparable promotion to university customers. Today, Cogent serves over 400 of the top educational institutions in the country. Many of these are universities that initially tested the Cogent network with a small backup connection, then ultimately reconfigured their networks and increased bandwidth to make Cogent their primary provider based on the combination of outstanding quality and overall cost savings they could achieve.

Today, Cogent serves several large cable customers in North America and Europe and expects this number to grow rapidly as the cable companies realize they can have more high quality bandwidth at a better price than any other provider can offer today.

About Cogent Communications

Cogent Communications (AMEX: COI) is the number one provider of Ethernet services in the United States as ranked by Ovum-RHK and is one of the fastest growing Tier 1 ISPs in the world. Its facilities based, all-optical network delivers ultra-high speed Internet access and transport services to businesses and service providers in major metropolitan areas. Cogent offers services across its 30,600-mile IP network spanning 12 countries located in North America and Europe.

The combination of technology, IP network architecture and unique business model has combined to help make Cogent one of the most popular solutions for reliable, cost-effective Internet service in the industry.

Cogent offers several focused services that complement its On-Net Internet access service including dedicated Off-Net (T1, T3) Internet service, colocation services in 30 data centers across North America and Europe, and Layer 2 Point-to-Point services in every On-Net market.

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 Diese E-Mail-Adresse ist vor Spambots geschützt! Zur Anzeige muss JavaScript eingeschaltet sein!.

# # #

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.

###