2019 Western & Southern Open – Women's singles

Madison Keys defeated Svetlana Kuznetsova in the final, 7–5, 7–6(7–5) to win the women's singles tennis title at the 2019 Cincinnati Masters.

Kiki Bertens was the defending champion, but lost in the second round to Venus Williams.

Naomi Osaka retained the world No. 1 singles ranking after the tournament. Ashleigh Barty and Karolína Plíšková were also in contention for the top ranking.

This tournament marked Maria Sharapova's final WTA Tour-level victory before her retirement; she defeated Alison Riske in the first round before losing to Barty in the second round.

Seeds
The top eight seeds received a bye into the second round. • 🇦🇺 Ashleigh Barty (semifinals)

• 🇯🇵 Naomi Osaka (quarterfinals, retired)

• 🇨🇿 Karolína Plíšková (quarterfinals)

• 🇷🇴 Simona Halep (third round)

• Kiki Bertens (second round)

• 🇨🇿 Petra Kvitová (second round)

• 🇺🇦 Elina Svitolina (third round)

• 🇺🇸 Sloane Stephens (third round)

• 🇧🇾 Aryna Sabalenka (third round)

• 🇺🇸 Serena Williams (withdrew)

• Anastasija Sevastova (first round)

• Belinda Bencic (first round, retired)

• 🇩🇪 Angelique Kerber (first round)

• 🇬🇧 Johanna Konta (first round)

• 🇨🇳 Wang Qiang (first round)

• 🇺🇸 Madison Keys (champion)

Seeds
• # 🇨🇿 Barbora Strýcová (qualifying competition, lucky loser)

• # 🇨🇳 Zhang Shuai (first round)

• # Monica Puig (qualifying competition, lucky loser)

• # 🇷🇺 Anastasia Pavlyuchenkova (first round)

• # 🇫🇷 Kristina Mladenovic (first round)

• # 🇨🇳 Wang Yafan (qualifying competition, lucky loser)

• # 🇫🇷 Alizé Cornet (first round)

• # Polona Hercog (withdrew)

• # 🇺🇸 Jessica Pegula (qualifying competition, lucky loser)

• # 🇷🇺 Veronika Kudermetova (qualified)

• # Jil Teichmann (first round)

• # 🇷🇺 Margarita Gasparyan (first round)

• # 🇹🇳 Ons Jabeur (qualified)

• # 🇰🇿 Elena Rybakina (first round)

• # 🇵🇱 Iga Świątek (qualified)

• # 🇺🇸 Lauren Davis (qualified)

Qualifiers
• # 🇸🇪 Rebecca Peterson

• # 🇺🇸 Lauren Davis

• # 🇷🇺 Veronika Kudermetova

• # 🇰🇿 Zarina Diyas

• # 🇺🇸 Jennifer Brady

• # 🇵🇱 Iga Świątek

• # 🇹🇳 Ons Jabeur

• # 🇦🇺 Astra Sharma

Lucky losers
• # Monica Puig

• # 🇨🇿 Barbora Strýcová

• # 🇨🇳 Wang Yafan

• # 🇺🇸 Jessica Pegula