iBasis Names Former IDT Executive, Prepaid Industry Veteran to Head Retail Prepaid Business

BURLINGTON, MASS. - September 16, 2003 - iBasis, Inc. (OTCBB: IBAS), the leader in Internet-based voice communications, today announced that, it named Jonathan Kaplan Vice President of Prepaid Solutions, to lead the company's recently launched entry into the retail prepaid market.

The retail prepaid calling card business, in the U.S. and worldwide, is one of the fastest growing segments of the telecommunications industry. According to forecasts from industry analyst firm Atlantic-ACM, revenues from calling cards sold in the U.S. will grow from $3.7 billion in 2002 to $5.1 billion in 2005.

"Unlike many smaller providers of prepaid cards and even the ILECs, iBasis has a worldwide VoIP network, which enables us to provide high quality service, equal to that of the largest and most established IXCs and PTTs, but with the much lower cost structure of the public Internet," said Ofer Gneezy, president and CEO of iBasis. "Jonathan's expertise in retail prepaid cards and his experience within the industry will help us to develop productive and lasting relationships with major distributors, who are the cornerstone of the prepaid business. As this business ramps up we expect to achieve a significant contribution from retail prepaid margins and cash flow, which are typically higher than those in the wholesale business."

iBasis' entry into the retail prepaid market is a natural progression of the services it has been providing to prepaid calling card operators through its IP CallCard billing and consumer account management platform and global network. Kaplan leads the iBasis Prepaid team in growing its existing prepaid business and developing the retail business in the U.S. and international markets. Prior to joining iBasis, Kaplan held executive and senior management positions with long distance carriers and prepaid calling card distributors including IDT, Horizon Phone Card, and LD Exchange, and founded Telecom Advisors, a prepaid calling card master distributor.

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.