2021 Open de Rennes – Singles
| Singles | |
|---|---|
| 2021 Open de Rennes | |
| Champion | Benjamin Bonzi |
| Runner-up | Mats Moraing |
| Score | 7–6(7–3), 7–6(7–3) |
Arthur Rinderknech was the defending champion but lost in the semifinals to Benjamin Bonzi.
Bonzi won the title after defeating Mats Moraing 7–6(7–3), 7–6(7–3) in the final.