Tchaptchet joined Southampton in the summer of 2018 and signed his first professional deal in December 2018, committing to the club until June 2021.
[2] On 16 January 2021, he made the bench for senior game for the first time, remaining as an unused substitute in a defeat against Leicester City.
[3] On 2 February 2021, he made his senior debut, coming on as a substitute for the final 12 minutes in a 9–0 loss to Manchester United.
[4] Tchaptchet left Southampton in July 2021 after failing to agree a new deal with the club.
He was a free agent and signed a two-and-a-half-year deal at the Stade des Alpes.