iBasis Adds David S. Lee to Board of Directors

Communications Industry Leader Brings 25 Years Experience, Extensive Knowledge of Chinese Telecommunications Industry to iBasis Board

BURLINGTON, MA - May 13, 2002 - iBasis, Inc., (Nasdaq: IBAS) today announced that David S. Lee will join its Board of Directors.

Mr. Lee, 64, has founded, served as chairman, and held senior executive positions at several communications technology companies, including ITT Corporation. Mr. Lee joined ITT after that company acquired Qume Corporation, a company he had co-founded in 1973. At ITT Qume, Mr. Lee held the positions of Executive Vice President from 1978 to 1981, and President, from 1981 through 1983. Mr. Lee later became President and Chairman of Data Technology Corporation and is currently Chairman of the Board of eOn Communications Corporation, Cortelco, and Cidco Communications. Mr. Lee also serves as a Regent for the University of California. Through his service on the Advisory Committee on Trade Policy and Negotiation for Presidents Bush (senior) and Clinton, and his current role on President George W. Bush's Council on the 21^st Century Workforce, Mr. Lee is one of the world's foremost experts on US-China commerce and the Chinese telecommunications industry. In addition to his executive and governmental positions, Mr. Lee is a member of the Board of Directors of the Pacific International Center for High Technology Research (PICHTR), ESS Technology Inc., Linear Technology Corporation, and Accela Inc. Mr. Lee holds an Honorary Doctorate of Engineering and a Bachelor of Science in mechanical engineering from Montana State University and an M.S. in mechanical engineering from North Dakota State University.

"I'm very pleased to have David Lee join our Board," said Ofer Gneezy, president and CEO of iBasis. "His extensive international experience, extraordinary record of high achievement, and technological expertise makes him an outstanding addition to our Board of Directors."

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.