iBasis Executive to Discuss VoIP Opportunities and Benefits at India VoIP Conference

Presentation Will Highlight Dramatic Growth and Continued Momentum in iBasis' India Traffic

BURLINGTON, MASS. - December 3, 2003 - iBasis, Inc. (OTCBB: IBAS), the leader in Internet-based voice communications, today announced that company Sr. Vice President of Worldwide Sales Dan Powdermaker will discuss the opportunities and benefits of voice over Internet protocol (VoIP) services in India at the VoIP India Conference to be held in New Delhi December 9 and 10.

In his remarks, Mr. Powdermaker intends to highlight the strategic benefits of VoIP and the dramatic growth in VoIP traffic to India as exemplified by iBasis' own experience. "Our India traffic increased 106% in Q3 2003 compared to Q3 2002, and that momentum is continuing through the fourth quarter," said Powdermaker. "Teledensity in India has increased dramatically in the last few years from about 2% in 2000 to 7% today. With a population of more than one billion people, there is obviously great potential for continued growth in India. VoIP offers the most efficient means of realizing that opportunity."

According to industry resource Telegeography, international phone traffic to India from the United States, its largest correspondent country, grew by more than 19% from 2001 to 2002. At the same time, VoIP traffic from the U.S. to India grew by more than 190%.

About iBasis

Founded in 1996, iBasis (OTCBB: IBAS) is a leading provider of wholesale international telecommunications services. For the past two years the company has been named by service providers as the best international wholesale carrier in Atlantic-ACM's annual International Wholesale Carrier Report Card¹. iBasis is a preferred provider for many of the largest carriers in the world, including AT&T, Cable & Wireless, China Mobile, China Unicom, MCI, Sprint, Telefonica, Telenor, and Telstra. iBasis has carried more than six billion minutes of international voice traffic over its global Cisco Powered Network™, and is one of the ten largest carriers of international voice traffic in the world². In addition to its wholesale international telecommunications services, iBasis provides retail prepaid calling cards to major distributors, utilizing the international iBasis Network. Based on its revenue growth from 1997 through 2001, iBasis was ranked the #8 fastest-growing technology company in North America and the #1 fastest-growing technology company in New England in the Technology Fast 500 national program 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.