2020–21 Thai League 3 National Championship
# 2020–21 Thai League 3 National Championship

The National Championship was the next stage from the regional stage of 2020–21 Thai League 3. The winners and runners-ups of each region would qualified to this round to finding three clubs promoting to the 2021–22 Thai League 2.

## Teams

| Team | Qualifying method |
| - | - |
| Lamphun Warriors | Northern region champions |
| Phitsanulok | Northern region play-off winner |
| Udon United | Northeastern region champions |
| Muang Loei United | Northeastern region runners-up |
| Pluakdaeng United | Eastern region champions |
| Chachoengsao Hi-Tek | Eastern region runners-up |
| Muangkan United | Western region champions |
| Rajpracha | Western region runners-up |
| Songkhla | Southern region champions |
| Krabi | Southern region runners-up |
| North Bangkok University | Bangkok Metropolitan region champions |
| Bangkok | Bangkok Metropolitan region play-off winner |

Note:

* ↑ The second-placed and the third-placed of the Northern region have similar points, so they must play-off to find a team to qualified to the national championship stage.
* ↑ The second-placed and the third-placed of the Bangkok Metropolitan region have similar points, so they must play-off to find a team to qualified to the national championship stage.

## Qualifying play-offs

### Play-off round

| Team 1 | Score | Team 2 |
| - | - | - |
| Northern region |||
| Maejo United | 1–2 | Phitsanulok |
| Bangkok metropolitan region |||
| Nonthaburi United S.Boonmeerit | 2–6 | Bangkok |

    Northern region
    Bangkok metropolitan region

## Group stage

### Upper region

| Pos | Team | Pld | W | D | L | GF | GA | GD | Pts | Qualification | LPW | UDU | CCH | PDU | PLK | MLU |
| - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
| 1 | Lamphun Warriors (C, P) | 5 | 4 | 0 | 1 | 8 | 5 | +3 | 12 | Qualification to the final and promotion to the 2021–22 Thai League 2 | — | 0–3 | 1–0 | — | 3–0 | — |
| 2 | Udon United | 5 | 3 | 1 | 1 | 8 | 3 | +5 | 10 | Qualification to the third place play-off | — | — | 3–1 | 0–0 | 0–1 | — |
| 3 | Chachoengsao Hi-Tek | 5 | 3 | 0 | 2 | 11 | 5 | +6 | 9 | | — | — | — | 2–1 | — | 7–0 |
| 4 | Pluakdaeng United | 5 | 2 | 1 | 2 | 10 | 5 | +5 | 7 | | 1–2 | — | — | — | 4–1 | 4–0 |
| 5 | Phitsanulok | 5 | 1 | 1 | 3 | 2 | 8 | −6 | 4 | | — | — | 0–1 | — | — | 0–0 |
| 6 | Muang Loei United | 5 | 0 | 1 | 4 | 2 | 15 | −13 | 1 | | 1–2 | 1–2 | — | — | — | — |

### Lower region

| Pos | Team | Pld | W | D | L | GF | GA | GD | Pts | Qualification | MKU | RAJ | KBI | SON | NBU | BKK |
| - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
| 1 | Muangkan United (P) | 5 | 3 | 2 | 0 | 7 | 1 | +6 | 11 | Qualification to the final and promotion to the 2021–22 Thai League 2 | — | 1–1 | — | 3–0 | — | 2–0 |
| 2 | Rajpracha (O, P) | 5 | 3 | 1 | 1 | 10 | 5 | +5 | 10 | Qualification to the third place play-off | — | — | — | 2–0 | 1–0 | — |
| 3 | Krabi | 5 | 2 | 1 | 2 | 6 | 6 | 0 | 7 | | 0–1 | 1–0 | — | — | — | — |
| 4 | Songkhla | 5 | 1 | 2 | 2 | 6 | 10 | −4 | 5 | | — | — | 2–2 | — | 2–1 | 2–2 |
| 5 | North Bangkok University | 5 | 1 | 1 | 3 | 3 | 5 | −2 | 4 | | 0–0 | — | 1–2 | — | — | 1–0 |
| 6 | Bangkok | 5 | 1 | 1 | 3 | 7 | 12 | −5 | 4 | | — | 3–6 | 2–1 | — | — | — |

* 1 2 North Bangkok University ahead on head-to-head record; North Bangkok University 3 pts, Bangkok 0 pts.

## Knockout stage

Winners, runners-up, and third place of 2020–21 Thai League 3 would be promoted to the 2021–22 Thai League 2.

### Third place play-off

**Summary**

| Team 1 | Agg. | Team 2 | 1st leg | 2nd leg |
| - | - | - | - | - |
| Udon United | 1–2 | Rajpracha | 1–0 | 0–2 |

**Matches**

Rajpracha won 2–1 on aggregate.

### Final

**Summary**

| Team 1 | Agg. | Team 2 | 1st leg | 2nd leg |
| - | - | - | - | - |
| Lamphun Warriors | 3–2 | Muangkan United | 2–0 | 1–2 (a.e.t.) |

**Matches**

Lamphun Warriors won 3–2 on aggregate.

## Teams promoted to 2021–22 Thai League 2

   * Lamphun Warriors (champions)

   * Muangkan United (runners-up)

   * Rajpracha (Third-placed)
