iBasis Ranked #1 International Wholesale Carrier for Second Consecutive Year

Carriers Rank VoIP Leader # 1 in Four of Six Categories; Second Only to AT&T in Voice Quality in Annual Atlantic-ACM Study

BURLINGTON, MASS. - February 18, 2003 - iBasis, Inc. (OTCBB: IBAS), the leader in Internet-based voice communications, today announced that it has been ranked by carriers as the world's best international wholesale carrier for the second year in a row in the 2003 International Wholesale Report Card, the acknowledged industry reference survey published annually by telecommunications research and advisory firm Atlantic-ACM.

iBasis was ranked #1 in four of the six categories in the study - Billing, Provisioning, Customer Service, and Pricing, and was second only to AT&T in Voice Quality and Code Coverage. Among VoIP carriers included in the study, iBasis was ranked first in all six categories.

The 2003 International Wholesale Report Card ranked the world's leading international wholesale carriers based on the opinions of carriers who use them. Respondents to the survey represented carriers that on average sent more than 1.4 billion minutes of international traffic annually. The study compiled individual ratings for customer service, provisioning, network quality, price competitiveness, products, and billing across many of the world's largest carriers, including AT&T, MCI Worldcom, Sprint, Cable & Wireless, France Telecom, Singapore Telecom, COLT, Primus, and VoIP providers iBasis and ITXC.

"This year marks the seventh year of our traditional wholesale telecommunications survey and the second year of the International Wholesale Report Card," said Dr. Judy Reed Smith, CEO of Atlantic ACM. "The results of our international study reflect the tremendous progress VoIP carriers have made in a very short period. In iBasis' case, their overall efforts, particularly in voice quality and billing, resulted in significant improvements that helped the company retain the #1 position in our study."

"This study confirms what many large carriers around the world have recognized, that VoIP has come of age, and that iBasis is the leader among wholesale providers of every technological stripe," said Ofer Gneezy, president and CEO of iBasis. "In the year since the last Wholesale Carrier Report Card, we completed an extensive upgrade of our global Cisco Powered Network, which included deploying a `next generation' switchless architecture and new patent-pending quality management technology. We also made dramatic improvements in our back-office systems and processes for billing. Retaining our #1 overall ranking, surpassing all but AT&T in voice quality and code coverage, and rising to the top in the billing, customer service and provisioning categories are evidence of our ability to execute in these essential areas."

The iBasis Network
The iBasis NetworkTM is the world's largest international Cisco Powered Network for Internet telephony, with more than 770 points of presence in approximately 90 countries. In 2002 the company completed the deployment of its next generation switchless architecture, leveraging its existing Cisco AS5000 gateways and SC 2200 SS7 technology, as well as new patent-pending iBasis technology for quality management and advanced routing. The company's Assured Quality Routing^® and PathEngineTM technology enable ongoing monitoring of network quality and automatic selection of best quality routes based on near real-time performance data. The result for iBasis customers is higher voice quality, call completion and call duration.

About Atlantic-ACM
ATLANTIC-ACM is an international strategy consulting and research firm founded in the early 1980's and is well known for its exclusive analysis of the competitive telecommunications industry in the United States. The company offers authoritative public reports on the industry, proprietary consulting to companies in converging and networked communications, and merger/acquisition counsel. ATLANTIC-ACM assists clients in evaluating telecommunications opportunities for successful investment, market entry, and long-term business planning. For more information visit the ATLANTIC-ACM website at www.atlantic-acm.com .

About iBasis

Founded in 1996, iBasis (OTCBB: IBAS) is a leading provider of wholesale international telecommunications services. Named each of the last two years by service providers as the #1 international wholesale carrier in Atlantic-ACM's annual International Wholesale Carrier Report Card, iBasis is a preferred provider for many of the largest carriers in the world. Customers include AT&T, Cable & Wireless, China Mobile, China Unicom, Sprint, Telefonica, Telenor, Telstra, and WorldCom. The company's global VoIP infrastructure, The iBasis NetworkTM, is the world's largest international Cisco Powered NetworkTM for Internet Telephony. Based on its revenue growth from 1997 through 2001, iBasis was ranked 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.

###

Assured Quality Routing, iBasis, and ConnectPoint are registered marks, The iBasis Network, Internet Central Office, Internet Branch Office, and IP CallCard are trademarks of iBasis, Inc. 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' most recent Forms 10-K and 10-Q, and the company's other SEC filings. We have no current intention to update any forward-looking statements.