Brazilian Carrier Intelig Interconnects with iBasis

One of the Largest Carriers in South America's Largest Market Connects to The iBasis NetworkTM to Expand International Service

BURLINGTON, MASS. - November 4, 2002 - iBasis, Inc.,(NASDAQ: IBAS) the leader in Internet-based voice communications, today announced that it has interconnected with Intelig, Brazil's second-largest long distance carrier, to terminate international calls in Brazil. Intelig is jointly owned by Sprint, France Telecom, and National Grid. In addition to terminating traffic for iBasis, Intelig is able to expand its international service quickly and cost-effectively by routing global voice traffic from its national fiber optic network to The iBasis Network(TM). Brazil, whose international traffic grew 44% to 1.2 billion minutes from 1999-2001(1), is one of the fastest-growing telecommunications markets in the world.

"Our relationship with Intelig provides us extensive access to South America's largest market and the fifth fastest-growing international traffic destination in the world," said Ofer Gneezy, president and CEO of iBasis. "Our interconnection with Intelig reflects the role of The iBasis Network as both a driver and enabler of telecommunications deregulation in the world's largest markets. Carriers in Brazil and other important deregulating markets look to our international service to help them compete more effectively and provide their customers the benefits of high quality, high value voice services. Our service to and from Brazil complements our service in other major Latin American market, including Mexico, Argentina, Colombia, and Uruguay."

"Our interconnection with iBasis is an important part of Intelig's strategy to bring the benefits of competition, quality and service excellence to the Brazilian telecommunications market. This is the main reason why we are celebrating this new partnership," said Leila Garcia, Carrier Services Director of Intelig.

iBasis in Latin America

These relationships highlight iBasis' significant market presence in Latin America - a region that is expected to experience a 50% annual growth rate in VoIP traffic through 2002(2). Through its more than 40 carrier partners in the region, which include Telefonica, Telecom Argentina, Orbitel and Telecom (Colombia), iBasis is able to provide service to Argentina, Chile, Colombia, Mexico, and Uruguay.

About Intelig

Intelig has been providing telecommunications services throughout Brazil since January 23, 2000. Through its modern, 100% digital network with nationwide coverage, the carrier offers voice and data solutions for residential, corporate, and carrier customers. Over 25 million users have already dialed the Intelig code number 23, and Intelig today has more than 1,000 corporate clients.

About iBasis

Founded in 1996, iBasis (Nasdaq: IBAS) is a leading provider of wholesale international telecommunications services to large carriers and other service providers worldwide. Named by service providers as the #1 international wholesale carrier in Atlantic-ACM's 2002 International Wholesale Carrier Report Card, iBasis is a preferred provider of international voice services for many of the largest carriers in the world, including AT&T, Cable & Wireless, China Mobile, China Unicom, Concert, Sprint, Telefonica, Telenor, Telstra, and WorldCom. The company's global VoIP infrastructure, The iBasis Network, spans more than 85 on-net countries and is the world's largest international Cisco Powered Network(TM) for Internet Telephony. Based on its revenue growth from 1997 through 2001, iBasis was named 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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iBasis is a registered mark, and The iBasis Network is a trademark of iBasis, Inc. Cisco Powered Network is a registered trademark 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; (iii) potential inability of the company to maintain its NASDAQ listing; and (iv) 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.

(1) According to industry analyst publication TeleGeography 2002

(2) Source: Probe Research 2001.