Everything Everywhere added 236,000 new contract customers during Q2 2011, as the popularity of Orange and T-Mobile broadband deals continued to rise.
The telecoms giant also reduced customer churn to 1.1 per cent across its two UK broadband brands, rewarding a significant investment in customer service during the quarter.
T-Mobile continued its recent turnaround with a third consecutive quarter of sustained growth between April and June 2011.
And revenues were also up at sister firm Orange, which is reasserting itself as a major player in the UK home broadband market.
Tom Alexander, Chief Executive Officer of Everything Everywhere, said the first half of 2011 was "a period of good progress" for the firm.
"Leveraging our unique strengths and market leadership, we are delivering on our strategic plan set out in September 2010 and are ahead of plan with our synergy capture," he stated.
"We are investing in building the best network experience for our customers and in creating platforms for growth."
Non-voice revenue, which includes earnings from broadband, accounted for 39 per cent of company turnover during the first six months of 2011, up from 36 per cent last year.