iBasis Launches Pingo™ RateWatcher™; to Pass Savings on to Prepaid Calling Service Customers

New Feature Saves Subscribers from Hassle of Comparing Prepaid Calling Cards; RateWatcher Delivers with Reductions up to 20% on Calls to Latin America

BURLINGTON, MA— January 26, 2005 — iBasis, Inc. (OTCBB: IBAS), a leader in international long distance, VoIP, and prepaid calling cards, today announced RateWatcher™, a new feature of Pingo®, the company's prepaid calling service which enables consumers to purchase calling cards via the www.pingo.com website. RateWatcher strengthens Pingo's position as "the last calling card you'll ever need™".

By actively monitoring evolving long distance costs around the world, RateWatcher finds opportunities to lower Pingo's costs, provide low international calling rates, and save Pingo subscribers from the chore of having to compare rates from a multitude of prepaid calling card offerings. RateWatcher reinforces Pingo's competitive position and broadens its customer base by increasing the number and diversity of competitively-priced destinations to include many of the most popular destinations for calls from the U.S.

With RateWatcher, Pingo customers benefit from the worldwide buying power of iBasis, one of the ten largest carriers of international phone calls in the world. iBasis has proven it's ability to deliver high quality service and cost savings to its customers through the technological superiority of it's own global VoIP network and an annual run-rate of more than five billion minutes.

"Pingo customers enjoy a significant advantage over subscribers to other prepaid services," said Ed Weisberg, vice president of eCommerce and Pingo at iBasis. "Unlike most competitive services, we own our network, and already carry a very high volume of traffic from our wholesale carrier customers. This gives us the leverage and the resources to be very effective in finding opportunities to reduce our costs and pass savings along to Pingo customers. As a result, Pingo appeals to a broad customer base representing a large volume of international calls from the U.S." RateWatcher Reduces Pingo Rates to Latin America

With the implementation of the RateWatcher program, effective immediately, Pingo has aggressively reduced its rates on calls to Latin American countries by 5 - 20%. The new rates begin as low as 3.2 cents per minute to Argentina. Other countries with substantial rate drops include The Dominican Republic, El Salvador, Ecuador, Guatemala, Bolivia, Columbia, Brazil, and Mexico.

Rates for calls to other countries around the world have also been reduced, and will continue to be adjusted on an ongoing basis as RateWatcher reveals opportunities to pass cost savings on to Pingo customers. Up-to-date rates are always available on the Pingo site at www.pingo.com.

About Pingo

Launched in September 2004, Pingo offers consumers high quality international calling services on a prepaid basis. Pingo customers save on calls to and from both landline and mobile phones. Mobile phones users in particular can benefit from Pingo's domestic toll-free access and lower rates on international calls. Minutes can be purchased using credit cards and debit cards at www.pingo.com. New customers begin saving immediately with a sign-up bonus of $5 worth of free calling and can receive additional $5 credits by successfully referring their friends to the Pingo service. Pingo leverages the iBasis global VoIP network, which includes direct connections to more than 100 countries worldwide and interconnections with more than 280 carrier customers. iBasis is one of the ten largest carriers of international calls in the world.

About iBasis

Founded in 1996, iBasis (OTCBB: IBAS) is a leading wholesale carrier of international long distance telephone calls and a provider of retail prepaid calling services, including the Pingo™ (www.pingo.com) web-based offering and disposable calling cards, which are sold through major distributors and available at retail stores throughout the U.S. iBasis customers include many of the largest telecommunications carriers in the world, including AT&T, Cable & Wireless, China Mobile, China Unicom, MCI, Sprint, Telefonica, Telenor, and Telstra. iBasis has carried more than ten billion minutes of international VoIP traffic over its global Cisco Powered™ network, and is one of the ten largest carriers of international voice traffic in the world¹. For three consecutive years service providers have named the Company as the best international wholesale carrier in ATLANTIC-ACM's annual International Wholesale Carrier Report Card². iBasis was also ranked the #1 fastest-growing technology company in New England in the 2002 and 2003 Technology Fast 50 programs sponsored by Deloitte & Touche. The Company can be reached at its worldwide headquarters in Burlington, Massachusetts, USA at 781-505-7500 or on the Internet at www.ibasis.com

The New England Technology Fast 50 program is presented by Deloitte & Touche and Hale and Dorr, in association with the sponsor, Mazonson Inc. In addition, Mass High Tech and Trinity Communications are associated with the program.

Assured Quality Routing, ConnectPoint, and iBasis are registered marks, Pingo, DirectVoIP, The iBasis Network, Internet Central Office, Internet Branch Office, and IP CallCard are trademarks of iBasis, Inc. Cisco and Cisco Powered are registered trademarks of Cisco Systems, Inc. All other trademarks are the property of their respective owners.