The move is expected to end Bournemouth’s interest in Arsenal keeper Aaron Ramsdale, while Mark Travers may now leave the club before Friday’s transfer deadline.
Kepa, has also extended his contract at Stamford Bridge until the end of the 2026 season.
His deal was due to expire in June 2025 which would have allowed him to leave Chelsea on a free transfer at the end of his loan spell with the Cherries.
Kepa remains the world’s most expensive ever goalkeeper having moved to the Blues in 2018 from his boyhood club Athletic Bilbao for £71m.
He has been training, along with 14 other players, away from manager Enzo Maresca’s first-team squad and is believed to have no future at Stamford Bridge.
The Spain international spent last season on loan at Real Madrid, where he made 20 appearances as a replacement for an injured Thibaut Courtois, winning La Liga and the Champions League.
