The 2017 Thai League 3 (known as the Euro Cake League Pro for sponsorship reasons) football season will be the first season of Thai League 3. 29 clubs will be divided into 2 groups (regions).
Promoted from 2016 Regional League Division 2 Northern Division
Promoted from 2016 Regional League Division 2 North-Eastern Region
Promoted from 2016 Regional League Division 2 Eastern Region
Promoted from 2016 Regional League Division 2 Central Region
Promoted from 2016 Regional League Division 2 Bangkok & field Region
Promoted from 2016 Regional League Division 2 Bangkok & Eastern Region
Promoted from 2016 Regional League Division 2 Western Region
Promoted from 2016 Regional League Division 2 Southern Region
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This round was featured by Udon Thani, the second place of 2017 Thai League 3 Upper Region and Trang, the second place of 2017 Thai League 3 Lower Region. Winners of third place play-off would promoted to 2018 Thai League 2.
3âÂÂ3 on aggregate. Udon Thani won on away goals.
This round was featured by Khonkaen, the first place of 2017 Thai League 3 Upper Region and Samut Sakhon, the first place of 2017 Thai League 3 Lower Region. Both winners and runners-up would promoted to 2018 Thai League 2 automatically.
Samut Sakhon won 5âÂÂ2 on aggregate.