The Post Office will enter a congested mobile market after an agreement was reached to share ISP EE's extensive network.
The move will expand the Post Office's presence in the telecoms sector which already has half a million customers in the home and broadband market. They will be competing against retailers Tesco, Sainsbury's and Asda.
The scheme will initially be rolled out in 50 Post Office branches before expanding nationwide later this year.
In research conducted by Truth, over a third of respondents said they would consider Post Office as their mobile provider.
This comes a month after new Post Office CMO Pete Markey expressed a desire to breathe new life into the brand.
Martin George, CCO at Post Office, said: “We are in an ideal position to offer a genuine alternative with over a third [of people] 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.
“Launching our own mobile service, using EE’s network, is a significant milestone in the Post Office’s journey of change and a testament to our continuing efforts to offer more essential services for our customers.”
George added: "Our network of over 11,500 branches combined with our online, and call centre presence, gives us the perfect platform to become one of the most credible providers of mobile services in the market."
The move may refresh the Post Office's financials after it emerged profits fell by £53m in the first half of this financial year.