2021 Western & Southern Open
| 2021 Western & Southern Open | |
|---|---|
| Date | August 15–22 |
| Edition | 120th (men) / 93rd (women) |
| Category | ATP Tour Masters 1000 (men) WTA 1000 (women) |
| Surface | Hard |
| Location | Mason, Ohio, United States |
| Venue | Lindner Family Tennis Center |
| Champions | |
| Men's singles | |
| Alexander Zverev | |
| Women's singles | |
| Ashleigh Barty | |
| Men's doubles | |
| Marcel Granollers / Horacio Zeballos | |
| Women's doubles | |
| Samantha Stosur / Zhang Shuai | |
The 2021 Western & Southern Open was a men's and women's tennis tournament played on outdoor hard courts from August 15–22, 2021, as part of the US Open Series. It was a Masters 1000 tournament on the 2021 ATP Tour and a WTA 1000 tournament on the 2021 WTA Tour.
The 2021 tournament was the 120th men's edition and the 93rd women's edition of the Cincinnati Open and took place at the Lindner Family Tennis Center in Mason, Ohio, a northern suburb of Cincinnati, in the United States, making its return to Ohio for the first time since the 2019 tournament after being held in New York City for 2020 due to the COVID-19 pandemic in the United States. It operated at full spectator capacity as participants were required to have tested negative for COVID-19 or be fully vaccinated.