A survey by thinkbroadband.com shows that O2's broadband service has been ranked the best service of the market.
O2, which uses unbundled internet infrastructure that it inherited after acquiring Be, was pitted against all the main ISPs like AOL, Orange, BT, Virgin, Sky broadband and Talktalk.
O2 scored highest in all categories tested - speed, reliability and customer service - with an overwhelming number of customers saying they were satisfied.
A separate survey by Intrepid research found out that four out of five customers who have moved over from other broadband providers to O2 are very satisfied with the service and are likely to recommend their friends.
Be was one of the first service providers to offer widespread high speed internet connection, with speeds starting at 24mbps for GBP 24.
O2 has also offered a special deal to all its mobile customers who wanted to have a bundled package deal.
At GBP 7.50 per month, its standard package, which provides up to 8mbps, is the cheapest on the market and does not come with any prohibitive download restrictions which tend to affect the lower end of the spectrum.
O2 also offer a 16mbps service for only GBP 10 per month and a 20mpbs one for GBP 15.