The Cincinnati Open has been a WTA 1000 tournament since 2009.
The WTA 1000 designation identifies one of the women’s tour’s highest-level regular events outside the Grand Slams and the WTA Finals. Cincinnati joined that category when the WTA reorganized its premier tournament structure in 2009.
The event’s women’s competition is played alongside the men’s ATP Masters 1000 tournament. Both sides use the Lindner Family Tennis Center in Mason, Ohio, and both are held on outdoor hard courts.
The category is sometimes confused with the tournament’s age or with its ATP status. Cincinnati was founded in 1899, while its men’s event is classified separately as an ATP Masters 1000 tournament.