Mobile operator Three has said there are 1.7 million customers using its 4G network since it switched on the service last year.
Three has offered an upgrade to 4G for customers free of charge in locations that have gone live, including London, Birmingham, Manchester, Reading and Liverpool.
The firm said usage of 4G since it started rolling out services in December had been high and that it would have 50 cities and 200 towns with 4G coverage by the end of the year.
With 1.7 million 4G customers Three is ahead of rivals such as Vodafone, which recently revealed it has 500,000 4G users, although it is charging for upgrades to the services.
Only EE has more 4G users, at over two million, although it has had a head start in the market by almost a year.
In total Three now has 7.9 million customers on its network after revealing it added 565,000 more over 2013 in its latest financial results. It said profits for the year doubled from £101m to £207m.
Three CEO David Dyson, said the figures proved that the firm’s efforts to shake up the mobile market were paying dividends.
“In 2013 we challenged the market with a series of innovative initiatives [and] in 2014, we will continue to innovate and put customer needs at the heart of our decision-making.”
Earlier this week rival EE announced it had signed a deal with NSN to upgrade its 4G network as it also looks to increase coverage on roads, rail routes and airport hubs.
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