The Post Office is to launch a mobile phone service, in partnership with EE from the autumn.
Building on its existing broadband and home phone service, the launch will be get underway in 50 branches and online initially before a nationwide rollout across all Post Office branches later this year.
The plan echoes other high-street names such as Tesco and Asda in launching a mobile service, in a bid to offer better value to customers who traditionally stick with the big providers.
Martin George, chief commercial officer at Post Office, said: "Our research tells us that people are seeking greater value, with one in three of those surveyed saying they intended to move away from one of the mainstream providers for their next service.
"We believe we are in an ideal position to offer a genuine alternative with over a third (36%) also saying they would consider us as their mobile provider. This is a fantastic vote of confidence in the Post Office brand - voted one of the most trusted brands in the UK."
Rob Kerr, mobiles expert at uSwitch.com, said: “No one could accuse the Post Office of resting on its laurels. First parcels, then travel money, insurance, broadband - and now mobile.
“But the Post Office is very late to the party. It will be hoping its trusted brand will give it a head start, but it needs to come up with an attractive pricing package that will catch the eyes of customers at the counter. Partnering with EE is a clever move that could give it edge when it comes to the growing 4G market."
The Post Office already offers a number of other financial products including travel money, travel insurance, savings accounts and mortgages.
Its home phone and broadband service already has around 500,000 customers and its deals start from £7 a month for 10Gb of broadband and weekend calls. Line rental charges start from £10 a month.