iBasis Names Roelant Lyppens Chief Financial Officer, to Replace Retiring Richard Tennant

BURLINGTON, Mass – 05/18/2010 – iBasis, a KPN company, today announced the appointment of Roelant Lyppens to the position of Chief Financial Officer. Lyppens replaces Richard Tennant, who will retire effective July 1, 2010. Tennant joined iBasis in October 2001 as Chief Financial Officer and served concurrently as senior vice president of finance and administration and as corporate treasurer, while iBasis was a publicly-traded company.

Mr. Lyppens comes to iBasis from MeesPierson, the investment banking division of the Fortis Bank Nederland/ABN Amro bank. At MeesPierson, Mr. Lyppens held the position of Executive Director, Corporate Finance & Capital Markets within the Telecom, Media, and Technology group. Prior to joining MeesPierson, Mr. Lyppens was CFO at PanTel Budapest (an alternative fixed-line telecom operator now part of Invitel), and worked in a variety of Finance functions over 12 years within KPN.

Were very pleased to welcome Roelant to the executive team of iBasis, where I am confident he will help us continue to build on the strong growth momentum we have established through the first half of the year, said John van Vianen, iBasis CEO. Also, we are very grateful for Dicks extensive contributions to iBasis over the years, and we wish him all the best as he enters retirement.

About iBasis
iBasis is one of the largest carriers of international long distance telephone calls in the world and a provider of retail prepaid calling services and enhanced services for mobile operators. The company offers a comprehensive portfolio of voice termination services, value-added messaging, signaling and roaming services for mobile operators, as well as outsourcing services for more than 1,000 carrier customers and partners, including many of the worlds largest fixed and mobile operators and VoBB service providers. iBasis operates a hybrid global network that includes one of the most extensive VoIP networks in the world, as well as TDM infrastructure. In December 2009 iBasis became a wholly-owned subsidiary of KPN. As a KPN company, iBasis leverages the full extent of KPNs global resources to help customers raise the value of their business. The Company can be reached at its worldwide headquarters in Burlington, Mass., USA at +1 781-505-7500 or on the Internet at www.ibasis.com.

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