Deloitte & Touche Cites iBasis As One of Ten Fastest-Growing Technology Companies in New England
for Second Consecutive Year

Company Receives Rising Star Honors for 2,994% Revenue Growth
From 1998 to 2000

BURLINGTON, MA-August 14, 2001- iBasis (Nasdaq: IBAS), the leader in advanced Internet-based voice communications, today announced that it has been recognized as one of the ten fastest-growing technology companies in New England by Deloitte & Touche, and Hale and Dorr, LLP. iBasis has been named a Rising Star in the firms' New England Technology Fast 50 program for the second consecutive year. iBasis was cited for this year's honor based on the company's three-year revenue growth from 1998 to 2000 of 2,994%.

Last year, iBasis was ranked as the #1 Rising Star in New England, making it the fastest-growing technology company based on its 1997 to 1999 revenue growth. The rankings of this year's ten New England Rising Stars will be announced by Deloitte & Touche at an awards ceremony on September 11, 2001.

"We have assembled a talented and dedicated team here at iBasis whose expertise and energy have helped us achieve this remarkable growth," said Ofer Gneezy, president and CEO of iBasis. "The ongoing, global shift of international voice traffic from traditional telecommunications transport to the Internet, and the emergence of compelling new IP-based communications services, such as speech-driven customer services and messaging, continue to power our business. Our current monthly international traffic volumes exceed those of most national carriers. We are gratified by this recognition from Deloitte & Touche that iBasis, unlike many companies in the current economic climate, continues to experience growth."

"To make the 2001 Rising Star list, companies must have sustained significant revenue growth in 2000, a year in which many technology companies were finding it difficult just to stay solvent," said Steve DiPietro, co-chair of the New England Technology Fast 50 program for Deloitte & Touche. He added, "We at Deloitte & Touche applaud iBasis for having the long-term vision to develop technologies that kept them growing while many competitors have faded away."

William F. Lee, managing partner of Hale and Dorr LLP and co-chair of the New England Technology Fast 50, commented, "The performance of these companies demonstrates that they have great products and services, and that those companies with the best technologies continue to move forward."

About The Rising Star and Fast 50 Program
Now in it's second year, the program's Rising Star award is presented by Deloitte & Touche and Hale and Dorr, LLP and is sponsored in association with Mazonson, Nasdaq, Trinity Communications, and Mass High Tech, The Journal of New England Technology.

To qualify for the New England Rising Star category, companies must have had operating revenues of at least $50,000 in 1998 and $1,000,000 in 2000, must be public or private companies headquartered in Massachusetts, New Hampshire, Maine, Rhode Island or Vermont; and be "technology companies" defined as companies that produce technology, manufacture a technology product, or devotes a high percentage of effort to research and development of technology.

Winners of the 22 regional Fast 50 programs and Rising Star categories in the United States and Canada are automatically entered in the Deloitte & Touche Technology Fast 500 program, which ranks North America's top 500 fastest growing technology companies. For more information on the Deloitte & Touche Fast 50 or Fast 500 programs, visit www.fast50.com .

About Deloitte & Touche
Deloitte & Touche, one of the nation's leading professional services firms, provides assurance and advisory, tax, and management consulting services through 30,000 people in more than 100 cities. The firm is dedicated to helping its clients and its people excel. Known as an employer of choice for its innovative human resources programs, Deloitte & Touche has been recognized as one of the "100 Best Companies to Work for in America" by Fortune Magazine for three consecutive years. Deloitte & Touche is part of Deloitte Tohmatsu, one of the world's leading professional services firms, with more than 90,000 people in over 130 countries. For more information, please visit Deloitte & Touche's web site at www.us.deloitte.com

About Hale and Dorr LLP
Hale and Dorr LLP is a nationally preeminent high-technology law firm, with over 400 attorneys and offices in Boston, Washington DC, Reston, VA, and New York. The firm has a strong reputation for advising and guiding emerging growth companies, especially those in the software, telecommunications and biotechnology industries. For more information, visit the firm's web site at http://www.haledorr.com/ .

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 SpeechPort^TM, a scalable, customizable ASP environment for speech-enabled business solutions, VoCore^SM messaging and the IP CallCard^TM 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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