Britain's EE will replace Vodafone as BT's mobile virtual network operator (MVNO) provider.
BT announced today that it has signed a multi-year MVNO agreement with EE, bringing an end to the nine-year deal it held with Vodafone.
The deal will see BT provide EE's mobile services to its 88,000 staff as well as its corporate customers.
BT said in a statement: "BT and EE have signed an agreement to proceed, on an exclusive basis, to a contract for EE to provide mobile virtual network operator (MVNO) services to BT's customers and employees.
"The multi-year agreement, subject to final contract, further strengthens the existing relationship in telecommunications between BT and EE."
BT opened a new tender in April for the MVNO partnership after Vodafone’s purchase of Cable & Wireless meant that BT could legally walk away from the deal it held with them.
EE already holds MVNO partnerships with more than 25 other firms including Virgin, Ikea, Talk Talk Business, Intercity, Talk Home and White Mobile.
BT secured spectrum in the 2.6GHz bandwidth at the Ofcom auction earlier this year at a cost of £186.5 million, but its plans for this bandwidth are not fully known. The 2.6GHz band boasts high capacity but comes with a limited range, making it well suited to densely populated urban areas, but less not so good for a national network.