# 2025 Nonthaburi Challenger – Singles

Wu Tung-lin was the defending champion but lost in the first round to Dalibor Svrčina.
Aslan Karatsev won the title after defeating Grégoire Barrère 7–6$^{(7–5)}$, 7–5 in the final.

## Seeds

* Marco Trungelliti (second round)
* Grégoire Barrère (final)
* Henri Squire (first round)
* Titouan Droguet (second round)
* Clément Chidekh (second round)
* Timofey Skatov (first round)
* Filip Cristian Jianu (first round)
* Benjamin Hassan (second round)

## Draw
### Key

* Q = Qualifier
* WC = Wild card
* LL = Lucky loser
* Alt = Alternate
* SE = Special exempt
* PR = Protected ranking
* ITF = ITF entry
* JE = Junior exempt
* w/o = Walkover
* r = Retired
* d = Defaulted
* SR = Special ranking

### Finals

| Semifinals | Semifinals | Semifinals | Semifinals | Semifinals | Final | Final | Final | Final |
| | Aslan Karatsev | 6 | 6 | | | | | |
| Q | Kimmer Coppejans | 3 | 1 | | | | | |
| Q | Kimmer Coppejans | 3 | 1 | | | Aslan Karatsev | 7$^7$ | 7 |
| | | | | | 2 | Grégoire Barrère | 6$^5$ | 5 |
| Q | Rei Sakamoto | 4 | 6 | 6$^6$ | 2 | Grégoire Barrère | 6$^5$ | 5 |
| 2 | Grégoire Barrère | 6 | 3 | 7$^8$ | | | | |

### Top half

| First round | First round | First round | First round | First round | Second round | Second round | Second round | Second round | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Semifinals | Semifinals | Semifinals | Semifinals |
| 1 | M Trungelliti | 7 | 7$^7$ | | | | | | | | | | | | | |
| Q | Maximus Jones | 5 | 6$^4$ | | 1 | M Trungelliti | 6$^4$ | 3 | | | | | | | | |
| | E Dalla Valle | 6 | 7$^{10}$ | | | E Dalla Valle | 7$^7$ | 6 | | | | | | | | |
| WC | Thanapet Chanta | 4 | 6$^8$ | | | | | | | E Dalla Valle | 1 | 1 | | | | |
| | G Oliveira | 4 | 3 | | | | | | | A Karatsev | 6 | 6 | | | | |
| | A Karatsev | 6 | 6 | | | A Karatsev | 6 | 6 | | | | | | | | |
| | J Sels | 3 | 5 | | 8 | B Hassan | 3 | 2 | | | | | | | | |
| 8 | B Hassan | 6 | 7 | | | | | | | | | | | A Karatsev | 6 | 6 |
| 3 | H Squire | 7$^7$ | 4 | 6$^1$ | | | | | | | | | Q | K Coppejans | 3 | 1 |
| | C Denolly | 6$^4$ | 6 | 7$^7$ | | C Denolly | 2 | 4 | | | | | | | | |
| | R Noguchi | 2 | 3 | | | L Neumayer | 6 | 6 | | | | | | | | |
| | L Neumayer | 6 | 6 | | | | | | | L Neumayer | 3 | 2 | | | | |
| WC | K Samrej | 4 | 6$^3$ | | | | | | Q | K Coppejans | 6 | 6 | | | | |
| Q | C Tabur | 6 | 7$^7$ | | Q | C Tabur | 3 | 3 | | | | | | | | |
| Q | K Coppejans | 7$^7$ | 4 | 6 | Q | K Coppejans | 6 | 6 | | | | | | | | |
| 7 | FC Jianu | 6$^1$ | 6 | 2 | | | | | | | | | | | | |

### Bottom half

| First round | First round | First round | First round | First round | Second round | Second round | Second round | Second round | Second round | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Semifinals | Semifinals | Semifinals | Semifinals | Semifinals |
| 5 | C Chidekh | 6 | 6 | | | | | | | | | | | | | | | |
| | O Prihodko | 3 | 2 | | 5 | C Chidekh | 3 | 0 | | | | | | | | | | |
| Q | Marat Sharipov | 6$^3$ | 6 | 4 | Q | R Sakamoto | 6 | 6 | | | | | | | | | | |
| Q | R Sakamoto | 7$^7$ | 2 | 6 | | | | | | Q | R Sakamoto | 4 | | | | | | |
| | G Mager | 7$^8$ | 2 | 6 | | | | | | | G Mager | 1$^r$ | | | | | | |
| Alt | M Cassone | 6$^6$ | 6 | 3 | | G Mager | 6 | 3 | 6 | | | | | | | | | |
| WC | W Trongcharoenchaikul | 6$^3$ | 2 | | 4 | T Droguet | 4 | 6 | 3 | | | | | | | | | |
| 4 | T Droguet | 7$^7$ | 6 | | | | | | | | | | | Q | R Sakamoto | 4 | 6 | 6$^6$ |
| 6 | T Skatov | 6$^4$ | 6$^6$ | | | | | | | | | | | 2 | G Barrère | 6 | 3 | 7$^8$ |
| | K Sultanov | 7$^7$ | 7$^8$ | | | K Sultanov | 6 | 6 | | | | | | | | | | |
| | G Blancaneaux | 5 | 5 | | Q | H Moriya | 4 | 2 | | | | | | | | | | |
| Q | H Moriya | 7 | 7 | | | | | | | | K Sultanov | 6$^5$ | 1 | | | | | |
| | T-l Wu | 6 | 4 | 3 | | | | | | 2 | G Barrère | 7$^7$ | 6 | | | | | |
| | D Svrčina | 2 | 6 | 6 | | D Svrčina | 5 | 6$^5$ | | | | | | | | | | |
| | F Arnaboldi | 4 | 6$^3$ | | 2 | G Barrère | 7 | 7$^7$ | | | | | | | | | | |
| 2 | G Barrère | 6 | 7$^7$ | | | | | | | | | | | | | | | |