2021 Adelaide International – Singles

Ashleigh Barty was the defending champion, but she lost in the second round to Danielle Collins, in a rematch of the previous year's semifinal.

Iga Świątek won the title, defeating Belinda Bencic in the final, 6–2, 6–2. Świątek did not drop a set throughout the entire tournament.

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

• # Belinda Bencic (final)

• #🇬🇧 Johanna Konta (second round)

• #🇧🇪 Elise Mertens (withdrew)

• #🇵🇱 Iga Świątek (champion)

• # Petra Martić (second round)

• #🇰🇿 Yulia Putintseva (second round)

• #🇨🇳 Wang Qiang (second round)

Seeds
• # 🇺🇸 Coco Gauff (qualified)

• # 🇺🇸 Bernarda Pera (first round)

• # 🇺🇸 Christina McHale (qualifying competition, lucky loser)

• # 🇺🇸 Madison Brengle (qualified)

• # 🇯🇵 Misaki Doi (qualifying competition, lucky loser)

• # 🇮🇹 Jasmine Paolini (qualified)

• # 🇨🇳 Wang Yafan (first round)

• # Kaja Juvan (qualifying competition)

• # 🇺🇸 Caty McNally (qualifying competition)

• # 🇷🇺 Liudmila Samsonova (qualified)

• # 🇦🇺 Astra Sharma (qualifying competition)

• # 🇦🇺 Maddison Inglis (qualified)

Qualifiers
• # 🇺🇸 Coco Gauff

• # 🇦🇺 Storm Sanders

• # 🇦🇺 Maddison Inglis

• # 🇺🇸 Madison Brengle

• # 🇷🇺 Liudmila Samsonova

• # 🇮🇹 Jasmine Paolini

Lucky losers
• # 🇯🇵 Misaki Doi

• # 🇺🇸 Christina McHale