The midfielder had been heavily linked with a move away from the south coast after impressing for Brighton & Hove Albion over the past four years.
Bissouma joined the Seagulls from Lille in 2018 and went onto make 124 appearances.
Graham Potter was quick to praise the Mali international following his departure, saying: “The transfer is a very good one for the club and player.
“Yves has shown his undoubted ability and been an important player during his time with us.
“Now he has a new challenge with Tottenham, including the opportunity to play Champions League football, and everyone at the club wishes him well.”
Here are today’s rumours...
1. Wolves closing in on €50m deal for Portugal midfielder
Wolverhampton Wanderers have reportedly had a club-record €45million bid (plus €5million add-ons) accepted for Sporting Lisbon's Matheus Nunes. The potential move would smash their £35.6m deal for Fabio Silva two years ago. (The Sun) | Getty Images
2. West Ham set sights on Danish international
West Ham are reportedly looking to sign Atalanta defender Joakim Maehle this summer. David Moyes had previously expressed interest in the 25-year-old, who has slipped down the pecking order in Bergamo. (Daily Star) | Getty Images
3. Red Devils top target could join Man City
Frenkie de Jong is reportedly more likely to join Manchester City this summer than United. It is thought that the Premier League champions could include Bernardo Silva in a swap deal. (The Hard Tackle) | Getty Images
4. Newcastle in battle with Tottenham for relegated star
Newcastle United are reportedly rivaling Tottenham and West Ham for Burnley's Dwight McNeil. The winger only managed one assist in the Premier League last season as the Clarets were relegated. (90 min) | Getty Images