2021 St. Petersburg Ladies' Trophy

The 2021 St. Petersburg Ladies' Trophy is a professional tennis tournament played on indoor hard courts. It is the 12th edition of the tournament and a WTA 500 tournament on the 2021 WTA Tour. The tournament is held between 15 and 21 March 2021.

Singles

 * 🇷🇺 Daria Kasatkina def. 🇷🇺 Margarita Gasparyan, 6–3, 2–1, ret.

Doubles

 * 🇺🇦 Nadiia Kichenok / 🇷🇴 Raluca Olaru def. 🇺🇸 Kaitlyn Christian / 🇺🇸 Sabrina Santamaria, 2–6, 6–3, [10–8].

Prize money
1Qualifiers prize money is also the Round of 32 prize money.
 * per team

Seeds

 * 1 Rankings as of March 8, 2021.

Other entrants
The following players received wildcards into the singles main draw:
 * 🇷🇺 Margarita Gasparyan
 * 🇷🇺 Daria Mishina
 * 🇷🇺 Vera Zvonareva

The following player received entry into the singles main draw using a protected ranking:
 * 🇧🇾 Vera Lapko

The following players received entry from the qualifying draw:
 * 🇷🇴 Jaqueline Cristian
 * 🇷🇺 Anastasia Gasanova
 * 🇷🇺 Kamilla Rakhimova
 * 🇦🇺 Arina Rodionova
 * Clara Tauson
 * 🇨🇳 Wang Xinyu

The following player received entry as a lucky loser:
 * 🇹🇷 Çağla Büyükakçay

Withdrawals

 * Before the tournament
 * Belinda Bencic → replaced by 🇧🇪 Kirsten Flipkens
 * 🇷🇴 Sorana Cîrstea → replaced by 🇧🇾 Aliaksandra Sasnovich
 * 🇧🇪 Elise Mertens → replaced by 🇹🇷 Çağla Büyükakçay
 * 🇰🇿 Yulia Putintseva → replaced by 🇷🇺 Daria Kasatkina
 * 🇺🇸 Alison Riske → replaced by 🇺🇦 Katarina Zavatska
 * Anastasija Sevastova → replaced by 🇧🇾 Vera Lapko
 * Jil Teichmann → replaced by 🇧🇬 Viktoriya Tomova
 * 🇷🇴 Patricia Maria Țig → replaced by 🇷🇴 Ana Bogdan
 * Donna Vekić → replaced by 🇪🇸 Paula Badosa

Retirements

 * 🇧🇾 Vera Lapko (cramping)
 * 🇷🇺 Margarita Gasparyan (lower-back injury)

Seeds

 * 1 Rankings as of March 8, 2021.

Other entrants
The following pair received a wildcard into the doubles main draw:
 * 🇷🇺 Daria Mishina / 🇷🇺 Ekaterina Shalimova
 * 🇷🇺 Elena Vesnina / 🇷🇺 Vera Zvonareva

The following pairs received entry using protected rankings:
 * Oksana Kalashnikova / 🇷🇺 Alla Kudryavtseva
 * 🇷🇸 Aleksandra Krunić / 🇷🇺 Alexandra Panova

Withdrawals

 * Before the tournament
 * 🇪🇸 Georgina García Pérez / Bibiane Schoofs → replaced by 🇷🇺 Ekaterina Alexandrova / 🇷🇺 Yana Sizikova
 * 🇺🇦 Lyudmyla Kichenok / Jeļena Ostapenko → replaced by  Jeļena Ostapenko / 🇷🇺 Valeria Savinykh
 * 🇷🇺 Veronika Kudermetova / 🇧🇪 Elise Mertens → replaced by 🇷🇴 Laura Ioana Paar / 🇩🇪 Julia Wachaczyk
 * 🇧🇾 Lidziya Marozava / 🇷🇴 Andreea Mitu → replaced by 🇧🇾 Lidziya Marozava / 🇧🇾 Aliaksandra Sasnovich
 * 🇧🇾 Vera Lapko / 🇸🇪 Cornelia Lister → replaced by 🇹🇷 Çağla Büyükakçay / 🇵🇱 Magdalena Fręch