There are 16 clubs in the league, with three promoted teams from
Thai League 2 replacing the three teams that were relegated from the
2020-21 season.
Sukhothai,
Trat and
Rayong were relegated at the end of the 2020–21 season after finishing in the bottom three places of the table. They were replaced by
2020-21 Thai League 2 champions
Nongbua Pitchaya. They were joined by runners-up
Chiangmai United, who also got promoted for the first time and
Khonkaen United, promotion playoff winner which was first held in 2020–21 season.
Stadium and locations :
Note: Table lists in alphabetical order. Personnel and sponsoring Note: Flags indicate national team as has been defined under
FIFA eligibility rules. Players may hold more than one non-FIFA nationality.
Managerial changes ==Foreign players==