iBasis Reports Third Quarter 2007 Financial Results

Company Concludes Transaction with KPN, Achieves Positive Net Income, Record Minutes and Record Gross Profit

BURLINGTON, MASS. - November 6, 2007 - iBasis, Inc. (NASDAQ: IBAS), the global VoIP company™, today announced results for the third quarter ended September 30, 2007.

Revenue for the third quarter of 2007 was $153.6 million, compared to $133.5 million for the third quarter of 2006. Net income for the third quarter was $0.2 million or $0.01 per share, compared to a net loss of $(3.0) million or $ (0.09) per share in the third quarter of 2006.

iBasis achieved $3.3 million in Adjusted EBITDA for the third quarter of 2007, compared to Adjusted EBITDA of $1.9 million in the third quarter of 2006. Adjusted EBITDA is a non-GAAP measurement presented to provide further information about the Company's operating trends.

Highlights of the third quarter include:

• Record minutes of 3.7 billion, a 3% sequential increase and 27% increase over Q3, 2006;
• Record gross profit, despite a slight decline in revenue;
• Strong sequential growth in Retail revenue and gross profit; and
• Eleventh consecutive quarter of positive cash flow.

Third Quarter Results for Trading and Retail Businesses:

Operational Milestones

Minutes of use on The iBasis Network™ in the third quarter 2007 were 3.7 billion, a 27% increase over the 2.9 billion minutes carried in the third quarter 2006, and a 3% increase over the 3.5 billion minutes in the second quarter 2007. Average revenue per minute was 4.20 cents, compared to 4.41 cents in the previous quarter. Average cost per minute was 3.71 cents, compared to 3.90 cents in the previous quarter, and average margin per minute was 0.49 cents for the third quarter compared to 0.51 cents for the previous quarter.

Comments on the Third Quarter

"Looking at our financial performance for Q3, improvement in cost of revenue enabled us to achieve growth in Gross Profit and expansion of Gross Margin even as we experienced a 1% sequential decline in revenue," said Ofer Gneezy, president and CEO of iBasis. "We also improved Adjusted EBITDA and Adjusted EBITDA margin.

"We remain confident in our ability to continue to grow organically, as well as to find significant opportunities to be a complete outsource solution for carriers' international traffic.

"In our Retail business, we launched the TruePrompts™ campaign, which we believe will enhance consumers' trust in our prepaid calling cards by guaranteeing delivery of the minutes announced or prompted on each call. In the short term, TruePrompts may temporarily slow growth in Retail until competitors throughout the segment implement similar measures, as it may appear to consumers that iBasis provides fewer minutes on its calling cards compared to a competitor's card. We believe this is a good development in the industry that will, in the longer term, highlight the competitive advantage of our lower cost structure."

Comments on iBasis-KPN Transaction

"We completed the transaction with Royal KPN N.V. to acquire KPN Global Carrier Services immediately following the end of the quarter. We expect to achieve synergies of $20 million over the medium term resulting from the combination of KPN Global Carrier Services and iBasis. Our initial focus is on capturing savings primarily in reduced cost of revenue, which we believe will drive increases in gross profit and gross margin. Since the completion of the transaction, we have begun the process of merging the organizations along functional lines and integrating our networks. We expect to address cross-selling and product integration beginning in 2008.

"The third quarter marks the end of one remarkable chapter in the story of iBasis and the start of an exciting new one. In just a little more than ten years we have built the largest international VoIP network in the world and taken a new idea from start-up to over $1 billion in revenue. Our merger with KPN Global Carrier Services propels iBasis to new heights and opens up new market opportunities. We are all very excited about the future of iBasis as one of the three largest carriers of international voice traffic in the world.

"This is the last quarter for which we will report results for iBasis as a stand-alone company. In the future, financials for all past periods through Q3 2007 will be those of KPN Global Carrier Services. Beginning with Q4 2007 the reported financial results will be those of iBasis and KPN Global Carrier Services combined. To enable more meaningful period-to-period comparisons we will also provide pro forma combined results for prior periods. We believe that pro forma combined results provide a more complete and meaningful picture of the third quarter."

Pro Forma Combined Nine Month Results*

The merger of KPN Global Carrier Services into iBasis provides scale and breadth of product offering that positions iBasis very well as a premier provider of international call termination. The table below shows our three sources of revenue: wholesale trading revenue from both iBasis and KPN Global Carrier Services, Outsourcing revenue from KPN and its subsidiaries, and Retail revenue from iBasis prepaid calling services. Like Retail Prepaid revenue, outsourcing revenue is traffic committed to iBasis. The majority of iBasis revenue continues to be from Wholesale Trading. In Q3 iBasis' outsource revenue was exclusively from KPN and its subsidiaries. The company sees significant growth opportunities in all three areas going forward.

Pro Forma Combined Sources of Revenue - Q3 2007*

iBasis-KPN Transaction Accounting

On October 1, 2007, the Company consummated a transaction with Royal KPN N.V. which resulted in the acquisition of KPN Global Carrier Services by iBasis. In conjunction with that transaction, on Monday, October 8, 2007 iBasis paid a dividend in the aggregate amount of $113 million, or $3.28 per share, to its stockholders of record as of the close of business on September 28, 2007.

Although in legal form iBasis has acquired KPN Global Carrier Services, KPN B.V. (a subsidiary of Royal KPN N.V.) holds a majority of the outstanding stock of the combined company. Accordingly, for financial reporting purposes, the merger has been treated as a reverse acquisition of iBasis by KPN Global Carrier Services under the purchase method of accounting.

As KPN Global Carrier Services is considered the acquiring company in this transaction, the financial results of KPN Global Carrier Services will become the historical financial results of the combined company and replace the historical financial results of iBasis. Thus, the financial results we will report for the full year 2007 will include the results of KPN Global Carrier Services alone for the first nine months and the financial results of the combined company for Q4 only. The comparative Q4 and full year 2006 financial results will be the historical financial results of KPN Global Carrier Services only. However, to make comparisons more useful, the Company will provide supplemental pro forma data.

Guidance

The Company believes that in Q4 2007 its consolidated revenues will be in the range of $370 million to $380 million.

As we are still in the early stages of integration, we are not providing guidance for 2008 at this time.

Q3 Results Conference Call

iBasis will host a conference call to discuss the Company's Q3 results, led by Ofer Gneezy, iBasis president & CEO on November 6, 2007 at 11:00 a.m. EST. The public is invited to listen to the simultaneous webcast by logging in through the iBasis investor relations website at investor.ibasis.com.

About iBasis

Founded in 1996, iBasis (NASDAQ: IBAS) is a leading wholesale carrier of international long distance telephone calls and a provider of retail prepaid calling services and enhanced services for mobile operators. iBasis customers include KPN, KPN Mobile, E-Plus, BASE, and many other large telecommunications carriers such as AT&T, Verizon, Vodafone, China Mobile, China Unicom, IDT, Qwest, Skype, Telecom Italia, Telefonica, and Yahoo. In October 2007, iBasis acquired KPN Global Carrier Services to create one of the three largest carriers of international voice traffic in the world, and KPN became a majority stockholder of iBasis. On a pro forma basis, the combined company carried more than 20 billion minutes of international voice over IP (VoIP) traffic in 2006. 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.