| Champ: | Alexander Zverev |
| Runner: | Nicolás Jarry |
| Score: | 6–3, 3–6, 7–6(10–8) |
| Draw: | 28 (4 / 3) |
| Seeds: | 8 |
| Edition: | 17th |
| Type: | singles doubles |
| After Year: | 2021 |
See main article: 2019 Geneva Open.
Alexander Zverev defeated Nicolás Jarry in the final, 6–3, 3–6, 7–6(10–8) to win the singles tennis title at the 2019 Geneva Open. Zverev saved two championship points en route to the title, in the final-set tiebreak.
Márton Fucsovics was the defending champion, but lost in the second round to Federico Delbonis.
The top four seeds receive a bye into the second round.