| 2019 Fairfield Challenger | |
|---|---|
| Date | 7–13 October |
| Edition | 5th |
| Surface | Hard |
| Location | Fairfield, California, United States |
| Champions | |
| Singles | |
 Christopher O'Connell | |
| Doubles | |
 Darian King /  Peter Polansky | |
The 2019 Fairfield Challenger was a professional tennis tournament played on hard courts. It was the fifth edition of the tournament which was part of the 2019 ATP Challenger Tour. It took place in Fairfield, California, United States between October 7 and October 13, 2019.
| Country | Player | Rank1 | Seed |
|---|---|---|---|
 USA | Steve Johnson | 98 | 1 |
| USA | Denis Kudla | 106 | 2 |
| USA | |||
 JPN | Taro Daniel | 127 | 4 |
 SLO | Blaž Rola | 128 | 5 |
| AUS | James Duckworth | 149 | 6 |
 ECU | Emilio Gómez | 151 | 7 |
| CAN | Peter Polansky | 168 | 8 |
| BAR | Darian King | 169 | 9 |
 ESP | Nicola Kuhn | 178 | 10 |
| USA | |||
| AUS | Christopher O'Connell | 193 | 12 |
| USA | Mitchell Krueger | 196 | 13 |
| USA | Jack Sock | 210 | 14 |
| USA | Ernesto Escobedo | 216 | 15 |
| USA | Maxime Cressy | 219 | 16 |
| USA | Donald Young | 238 | 17 |
The following players received wildcards into the singles main draw:
The following player received entry into the singles main draw as an alternate:
The following players received entry from the qualifying draw:
Felix Corwin
Sem Verbeek The following player received entry as a lucky loser:
Christopher O'Connell def. Steve Johnson 6–4, 6–4. Darian King / Peter Polansky def. 
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