WASHINGTON, D.C., April 3, 2006 - Cogent Communications Group, Inc. (NASDAQ: CCOI), a multinational, Tier One Internet Service Provider (ISP), announced today that it is offering a new feature that will redefine the industry standard for burstable bandwidth service. For excess bandwidth usage, customers will be billed at a 90th percentile instead of at the current industry norm of the 95th percentile. By billing the service at the 90th percentile, Cogent continues to lead the industry on price and now provides even more competitive pricing to customers whose bandwidth requirements vary from month to month. This is an especially compelling benefit for customers such as universities, online gaming and other web-based content providers that tend to experience event-driven or seasonal spikes in Internet traffic.

Nth Percentile calculation is a mathematical algorithm that most large service providers employ to calculate monthly bills for customers of burstable service in order to accommodate peaks above baseline service agreements. Most service providers, including Cogent, measure bandwidth levels every 5 minutes over the course of a month for all customers. Cogent's 90th percentile billing throws out the highest 10% of bandwidth usage peaks versus the 5% offered by other ISPs. This translates into lower bills for Cogent customers.

"Cogent has been the price leader in the industry since we began to sell our Internet access service in 2000. We leverage our advanced technology and simplified internal systems to provide customers with high quality service at the lowest commodity-based pricing in the industry. As bandwidth demand increases significantly through the growth of applications such as VoIP, IPTV and video on demand, Cogent will continue to lead the industry by providing unprecedented value to other service providers and corporate end users," said Dave Schaeffer, CEO of Cogent Communications.

Cogent's 90th percentile billing goes into effect today. The 90th percentile offer is made to new customers looking to get more value out of their Internet service. For more details on this offer, go to Cogent's home page www.cogentco.com and look under "Special Price Promotions"

About Cogent Communications

Cogent Communications (NASDAQ: CCOI) is the number one provider of Ethernet services in the United States based on the number of ports in service as ranked by Ovum-RHK and is one of the fastest growing Tier One ISPs in the world. Its facilities based, all-optical network is the largest IP-only network in the world delivering over 80 Gigabits of capacity in the United States and 40 Gigabits of capacity in Europe. Cogent 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 14 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 28 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 This email address is being protected from spambots. You need JavaScript enabled to view it..

# # #

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.

###