O2 has been recognised for its customer service in both fixed-line broadband and mobile broadband services.
The provider came out as the top provider in the recent JD Power and Associates' 2008 UK Fixed Broadband and UK Mobile Broadband ISP Customer Satisfaction studies.
In the fixed-line rankings, O2 claimed a score of 767 out of 1,000, bettering the 706 registered by Sky and 672 from Virgin Media.
A rating of 712 was enough to take the mobile broadband honours - T-Mobile trailed with 683, while Vodafone recorded 655.
O2's marketing director, Peter Rampling, said that the hard work the provider had put into customer relations had paid off.
"This is a fantastic recognition of the focus we've had on the customer experience.
"For both our mobile and home broadband services, we took our time coming to market to place the necessary emphasis on getting the customer experience right."