The National Championship was the next stage from the regional stage of

2021–22 Thai League 3 The 2021–22 Thai League 3 is the 5th season of the Thai League 3, the third-tier professional league for association football clubs in Thailand, since its establishment in 2017, also known as Blue Dragon League due to the sponsorship deal wit ...

. The winners and runners-ups of each region would qualify for this round to find 3 clubs promoting to

2022–23 Thai League 2 The 2022–23 Thai League 2 is the 25th season of the Thai League 2, the second-tier professional league for Thailand's association football clubs, since its establishment in 1997, also known as M-150 Championship due to the sponsorship deal wit ...

Teams

Group stage

Upper region

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Lower region

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Knockout stage

Winners, runners-up, and third place of

would be promoted to the

Third place play-off

Summary

Matches

''Nakhon Si United won 4–3 on aggregate.''

Final

Summary

Matches

''Uthai Thani won 3–1 on aggregate.''

Teams promoted to 2022–23 Thai League 2

Uthai Thani Uthai Thani ( th, อุทัยธานี, ) is a town (''thesaban mueang'') in Thailand, capital of the Uthai Thani Province, in the upper central region of the country. It includes the entire ''tambon'' Uthai Mai of Mueang Uthai Thani distr ...

(champions) :* Krabi (runners-up) :* Nakhon Si United (third-placed)

References

{{DEFAULTSORT:2021-22 Thai League 3 National Championship Thai League 3 3