Albacom Interconnects with iBasis for International VoIP Services

Leading Competitive Carrier in Italy Expands iBasis European Presence

BURLINGTON, MASS. - June 9, 2003 - iBasis, Inc. (OTCBB: IBAS), the leader in Internet-based voice communications, today announced that Albacom, the leading competitive carrier in Italy, is interconnecting with The iBasis NetworkTM for international telecommunications services. By interconnecting with iBasis Albacom will be able to route international voice traffic over The iBasis Network, the world's largest Cisco Powered Network for Internet telephony, as well as complete calls for iBasis over Albacom's extensive network in Italy.

Albacom joins the more than 170 carriers worldwide who have formed partnerships with iBasis. By providing Tier One quality international service to these carriers, iBasis has become one of the world's 10 largest carriers of international traffic¹ and was recently ranked by global service providers as the world's best international wholesale carrier².

Italy's international traffic is growing rapidly. According to TeleGeography 2003, the volume of international telephone traffic outbound from Italy to other countries has grown 48% from 3.3 billion minutes in 1999 to 4.8 billion minutes in 2001. Through its interconnection with Albacom, iBasis carries a portion of this traffic over the iBasis Network. In addition, iBasis sends traffic from its global network to Albacom for completion in Italy.

"Fast-growing competitive carriers like Albacom are recognizing the compelling value proposition of Tier One quality VoIP from iBasis," said Ofer Gneezy, president and CEO of iBasis. "By leveraging our many carrier relationships around the world, Albacom is able to deliver the highest quality international service while maintaining its focus on developing innovative products and growing its customer base."

About Albacom Albacom is the first and largest Italian operator focused on the telecommunications field dedicated to business, both in terms of the range of services offered as well as in terms of turnover. Founded in September 1995 as the result of a strategic agreement between BT (British Telecommunications) and Banca Nazionale del Lavoro, Albacom has seen the number of its shareholders increase with the arrival of Mediaset in May 1996 and of Eni in December 1997. With the arrival of the latter shareholder, the Albacom S.p.A. shareholders are as follows: British Telecommunications 23% and Banca Nazionale del Lavoro 22.5%, ENI 35% and Mediaset 19.5%.During the fiscal year ended March 31, 2002, Albacom had a turnover of 578 million Euro (+ 24% with respect to the preceding fiscal year) operating exclusively in the business market and counting on a portfolio that, today, exceeds 200,000 corporate clients. For further information, see www.albacom.it.

About iBasis

Founded in 1996, iBasis (OTCBB: IBAS) is a leading provider of wholesale international telecommunications services. Named by service providers in each of the last two years as the #1 international wholesale carrier in Atlantic-ACM's annual International Wholesale Carrier Report Card, iBasis is a preferred provider for many of the largest carriers in the world. Customers include AT&T, Cable & Wireless, China Mobile, China Unicom, Sprint, Telefonica, Telenor, Telstra, and WorldCom. The company's global VoIP infrastructure, The iBasis NetworkTM, is the world's largest international Cisco Powered NetworkTM for Internet Telephony. 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.

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