| 2025 Fairfield Challenger | |
|---|---|
| Date | 6–12 October |
| Edition | 9th |
| Surface | Hard |
| Location | Fairfield, California, United States |
| 2024 Champions | |
| Singles | |
 Learner Tien | |
| Doubles | |
| Ryan Seggerman / Patrik Trhac | |
The 2025 Fairfield Challenger was a professional tennis tournament played on hardcourts. It was the ninth edition of the tournament which was part of the 2025 ATP Challenger Tour. It took place in Fairfield, California, United States between October 6 and October 12, 2025.
| Country | Player | Rank1 | Seed |
|---|---|---|---|
 LBN | Benjamin Hassan | 187 | 1 |
 KAZ | Dmitry Popko | 214 | 2 |
 CZE | Marek Gengel | 245 | 3 |
| USA | Garrett Johns | 294 | 4 |
 JOR | Abdullah Shelbayh | 302 | 5 |
 GER | Mats Rosenkranz | 315 | 6 |
 AUS | Moerani Bouzige | 320 | 7 |
| USA | Michael Mmoh | 321 | 8 |
The following players received wildcards into the singles main draw:
Andrew Fenty Dominique Rolland Emon van Loben SelsThe following player received entry into the singles main draw using a protected ranking:
Micah BraswellThe following player received entry into the singles main draw through the Junior Accelerator programme:
The following player received entry into the singles main draw as an alternate:
The following players received entry from the qualifying draw:
Evan Bynoe
Jay Dylan Hara Friend
Darian King 
Roger Pascual Ferrà Quinn Vandecasteele Edward Winter 
vs. / vs. /