Initially, there were plans for Gittens to move to Chelsea before the Club World Cup, but the deal fell through due to a disagreement over the transfer fee.
Chelsea has now made a successful offer of €65 million, and Gittens will undergo a medical examination before completing his transfer.
As a former Manchester City academy graduate, Gittens will become the fifth player from his background to join the current Chelsea squad. Chelsea manager Enzo Maresca also has a connection to Manchester City.
At his previous club, Gittens had a strong start to the 2024-25 season but has faced challenges since then. He has scored 12 goals and provided three assists in 49 games across all competitions.