| Champ: |  Camila Giorgi |
| Runner: |  Karolína Plíšková |
| Score: | 6–3, 7–5 |
| Draw: | 56 (8 / 5) |
| Seeds: | 16 |
| Before Name: | Rogers Cup – Women's singles |
| Before Year: | 2019 |
| After Year: | 2022 |
See main article: 2021 National Bank Open.
Camila Giorgi defeated Karolína Plíšková in the final, 6–3, 7–5 to win the women's singles tennis title at the 2021 Canadian Open. It was her third career WTA Tour title, her first at the WTA 1000 level, and her first since Linz in 2018.
Bianca Andreescu was the defending champion from when the event was last held in 2019,[1] but lost in the third round to Ons Jabeur.[2]
The top eight seeds received a bye into the second round.