Callmate Telips, The First Long Distance And International Private Operator In Pakistan Selects iBasis for International Voice Services.

WASHINGTON -- iBasis Gains Advantageous Access to Large Telecom Market Through DirectVoIP(TM) Interconnection with Premier Competitive Carrier

iBasis, Inc. (OTCBB: IBAS), a leader in international long distance, VoIP, and prepaid calling cards, today announced at The Global Telecommunications Meeting that Callmate Telips, the first long distance and international private operator in Pakistan, has interconnected with The iBasis Network(TM) for international voice services. The interconnection enables Callmate Telips to route international voice traffic over The iBasis Network, the leading global VoIP network, as well as complete calls for iBasis in Pakistan.

Callmate Telips has taken advantage of the iBasis DirectVoIP interoperability solution to implement a direct IP connection between its Huawei IP Backbone infrastructure and the iBasis Cisco Powered(TM) network. Interoperability was assured through extensive testing in the DirectVoIP Certified Program, thereby simplifying the process of interconnecting the Callmate Telips infrastructure to iBasis' global VoIP network.

Callmate Telips will benefit from the lower capital and operational costs of VoIP and will have immediate access to iBasis' global VoIP network, which comprises direct routes to more than 100 countries.

"As the first company to be awarded the Long Distance and International (LDI) license in Pakistan and the first to launch LDI operations, we wanted to complement that advantage with high quality service and efficiency in our global network partner," said Ajmal Ansari, CEO of Callmate Telips. "iBasis has proven its leadership in all aspects of international VoIP, and we look forward to a very successful relationship."

"Callmate Telips is a leading provider of calling card and international long distance services and an innovator in using advanced technology to offer high quality and reasonably-priced services to consumers," said Ofer Gneezy, president and CEO of iBasis. "This new relationship reflects the continued migration of international traffic to VoIP which promises to make worldwide communication economically feasible for developing nations."

With only four million fixed telephone lines serving a population of more than 150 million (as of November 2003), demand for telecommunications services in Pakistan is very high. Minutes from international calls originating in Pakistan grew 33% from 2002 to 2003, with Saudi Arabia, United Kingdom, United Arab Emirates, United States, and Germany the most popular routes. More than 1.7 billion minutes of international traffic terminated in Pakistan in 2003, representing more than 46% growth during the prior two years, according to Telegeography 2005. The interconnection with Callmate Telips provides iBasis with tremendous opportunity to capture significant share of both ends of this growing market.

About Callmate Telips

Callmate Telips Telecom, Ltd. was formed as a result of the merger between Telips and Callmate, the two leading payphone and calling card brands in Pakistan. Callmate Telips is a public company listed on the Karachi stock exchange. Callmate Telips is one of the pioneers in payphones and calling card business and has become the first competitive long distance and international (LDI) operator in Pakistan. Callmate Telips possesses the requisite infrastructure, experience and ability to become the leading private telecom operator in Pakistan. For more information, visit www.cttelecom.net.

About iBasis

Founded in 1996, iBasis (OTCBB: IBAS) is a leading wholesale carrier of international long distance telephone calls and a provider of retail prepaid calling services, including the Pingo(TM) web-based offering (www.pingo.com) and disposable calling cards, which are sold through major distributors and available at retail stores throughout the U.S. iBasis customers include many of the largest telecommunications carriers in the world, including AT&T, Cable & Wireless, China Mobile, China Unicom, MCI, Sprint, Skype, and Telefonica. iBasis carried approximately 5 billion minutes of international voice over IP (VoIP) traffic in 2004, and is one of the ten largest carriers of international voice traffic in the world(1). For three consecutive years service providers named iBasis the best international wholesale carrier in ATLANTIC-ACM's annual International Wholesale Carrier Report Card(2). iBasis was also ranked among the fastest-growing technology companies in New England in the 2002, 2003, and 2004 Technology Fast 50 programs 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 and iBasis are registered marks, Pingo, DirectVoIP,

PremiumCertified, and The iBasis Network are trademarks of iBasis, 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, profitability, future capital expenditures, and cash flows 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 and margin 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 the Company's 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.

(1) Telegeography 2005 data compared with iBasis 2004 traffic volume.

(2) ATLANTIC-ACM International Wholesale Carrier Report Card - 2002, 2003, & 2004.