iBasis President and CEO at Vortex 2001:
All Voice Moving to the Internet; Speech to Drive The Web

Ofer Gneezy Defines Key Drivers of Rapid Global Growth
in Internet Telephony, Enhanced Voice Services

DANA POINT, CA - May 23, 2001 - iBasis, Inc., (Nasdaq:IBAS), the leader in advanced Internet-based voice communications, today announced that its president and CEO, Ofer Gneezy, will discuss key drivers of the global growth in VoIP services as part of an industry panel entitled "VoIP Reality Check" on Thursday, May 24, at the prestigious VORTEX 2001 conference, held here. Citing the more than 2,000% growth in international Voice-over-IP (VoIP) call volumes since 1998¹, as well as recent advances in enabling technologies such as high-scale VoIP gateways, IP-based enterprise solutions, speech recognition, and new, multimedia Internet standards, such as VoiceXML and SIP (Session Initiation Protocol), Mr. Gneezy is expected to outline the strategic drivers, market trends and industry shifts that are transforming the $840 billion telecommunications services industry².

iBasis, a leading global provider of voice services to the world's largest carriers and companies, with service facilities in 65 countries, has contributed significantly to this growth, regularly carrying the equivalent of 10-35 percent of all US phone traffic to 14 countries, including China and Russia, over its Voice-over-Internet-Protocol network.

"Traditional telecommunications is in the midst of a transition. High fixed costs, decreasing margins and slowing revenue growth are driving large carriers to new carrier-class VoIP services and pushing many smaller circuit-switched carriers out of the market. With the emergence of important new speech-enabled business services available from any phone, global networks like our own, and robust VoIP solutions for the enterprise, Internet telephony has proven its superiority to expensive, closed, legacy networks. VoIP is now nearing the tipping point, after which all new voice solutions will be IP-based," said Gneezy. "Early on, some saw promise in PC-to-phone applications. We were always skeptical of this service model, in which quality is sacrificed and the highest cost element - that of completing a call on the traditional telephone network - is retained. It comes as no surprise that these services, most of which relied on advertising revenue or on dot-com business, have quickly fallen out of favor."

"Instead we see enormous potential in speech-driven business services delivered over a global IP-based voice infrastructure. In these enhanced voice solutions, a call to conduct a transaction or obtain information begins on a mobile or fixed phone and accesses an application server, preserving call quality without incurring the cost of call completion on the phone network. Furthermore, these solutions are simple to understand and use and do not require new handsets or any special software, enabling mobile carriers to quickly provide differentiated, higher-margin services that can connect the phone to the world of Web services, via voice, without depending on the roll-out of 3G networks."

About VORTEX 2001
VORTEX 2001 is an exclusive, invitation-only event for senior executives that brings together all the key elements -- leadership, thought, funding, and regulatory expertise -- to shape the future of the network business and the technologies that drive it. VORTEX 2001 is being held May 22-24, 2001, at the Ritz-Carlton Laguna Niguel resort in Dana Point, California. Attendance at VORTEX is by invitation only. To learn more about Vortex 2001 visit http://www.idgexecforums.com/vortex2001.

About iBasis
Founded in 1996, iBasis (Nasdaq: IBAS) is the leader in advanced Internet-based voice communications. iBasis delivers toll quality international voice services and provides the infrastructure for hosted communications solutions, including messaging and speech-enabled content, e-commerce and customer service applications. The company's customers include many of the largest enterprises and carriers in the world, including AT&T, Cable & Wireless, China Mobile, China Unicom, Concert, ExxonMobil, Gannett, H&R Block, Home Shopping Network, Morgan Stanley, NTT, Telstra, Sabre Group, Sprint, Western Union, WorldCom, and Verizon. iBasis' hosted, enhanced service solutions include SpeechPortTM, a scalable, customizable ASP environment for speech-enabled business solutions, VoCore^SM messaging and the IP CallCardTM pre- and post-paid calling card platform. The iBasis Network is the world's largest international Cisco Powered Network for Internet Telephony and the first to receive the Unified Communications-Cisco Powered Network (UC-CPN) designation. iBasis is listed in both the Russell 2000® and Russell 3000® Indexes. The company can be reached at its worldwide headquarters in Burlington, Mass., USA at 781-505-7500 or on the Internet at http://www.ibasis.com.

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Assured Quality Routing and iBasis are registered marks, VoCore is a service mark, The iBasis Network, Internet Central Office, Internet Branch Office, IP CallCard, SpeechPort, IPort, and PriceInteractive 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 new voice-based Internet services and the timing and amount of revenue generated by these services; (ii) fluctuations in the market for and pricing of VoIP 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, 2000, and the company's other SEC filings.