iBasis Names Kenny Wan Vice President for Asia-Pacific Region

Former Qwest and Sprint Sales Executive Brings 18 Years of Experience, Extensive Knowledge of Asian Telecom Markets to International VoIP Carrier

BURLINGTON, MA - June 3, 2002 - iBasis, Inc., (Nasdaq: IBAS) the leader in Internet-based communications, today announced that Kenny Wan has been named vice president of Sales for the Asia-Pacific region.

In this position, Kenny Wan will drive the company's sales strategies and initiatives for the Asia-Pacific region. Mr. Wan is a proven telecommunications sales executive who brings to iBasis an extensive knowledge of the Asian markets and more than 18 years of sales management experience with major telecommunications providers. Prior to joining iBasis, Mr. Wan was vice president of Asia Sales for Qwest Communications. Prior to this role, Mr. Wan was regional sales director of Asia for Sprint International and served as country manager in the Philippines for Global One. Mr. Wan has also held technical sales positions with Digital Equipment Corporation. Mr. Wan holds a Bachelor of Science degree from Essex University in the U.K., as well as a Master of Science degree in electrical and electronic engineering from the University of Hong Kong.

"We are delighted to have Kenny Wan on board heading up our sales efforts in the Asian-Pacific region," said Ofer Gneezy, president and CEO of iBasis. "As a telecom industry veteran and Hong Kong native, Kenny combines an impressive record of achievement with a deep understanding of the Asian communications markets."

About iBasis
Founded in 1996, iBasis (Nasdaq: IBAS) is the leader in Internet-based voice communications. iBasis delivers toll quality international voice services and provides the infrastructure for hosted communications solutions, including speech-enabled content, e-commerce and customer service applications. The company's customers include many of the largest carriers and enterprises in the world, including AT&T, Cable & Wireless, China Mobile, China Unicom, ExxonMobil, Gannett, H&R Block, Home Shopping Network, Morgan Stanley, NTT, Qwest, Telefonica, Telenor, Telstra, Sabre Group, Sprint, Western Union, and WorldCom. iBasis' hosted, enhanced service solutions include SpeechPortTM, a scalable, customizable ASP environment for speech-enabled business solutions. The iBasis Network is the world's largest international Cisco Powered Network for Internet Telephony. iBasis is listed in both the Russell 2000® and Russell 3000® Indexes. 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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Assured Quality Routing and iBasis are registered marks; The iBasis Network, Internet Central Office, Internet Branch Office, IP CallCard and SpeechPort are trademarks of iBasis, Inc. or its subsidiaries. Cisco and Cisco Powered Network are registered trademarks of Cisco Systems, Inc. All other trademarks are the property of their respective owners.

Except for historical information, all of the expectations, projections and assumptions contained in the foregoing press release, including those relating to the company's current expectations regarding revenue growth, sources of revenue, margin improvement and future capital expenditures constitute forward-looking statements under the Private Securities Litigation Reform Act of 1995 and involve risks and uncertainties. Important factors that could cause actual results to differ materially from such forward-looking statements include, but are not limited to, (i) the extent of adoption of the company's services and the timing and amount of revenue generated by these services; (ii) fluctuations in the market for and pricing of these services; and (iii) the other considerations described as "Risk Factors" in iBasis' Annual Report on Form 10-K for its fiscal year ended December 31, 2001, and the company's other SEC filings. We have no current intention to update any forward-looking statements.