2021 Berkeley Tennis Club Challenge

The 2021 Berkeley Tennis Club Challenge was a professional women's tennis tournament played on outdoor hard courts. It was the third edition of the tournament which was part of the 2021 ITF Women's World Tennis Tour. It took place in Berkeley, California, United States between 27 September and 3 October 2021.

Seeds

 * 1 Rankings are as of 20 September 2021.

Other entrants
The following players received wildcards into the singles main draw:
 * 🇺🇸 Reese Brantmeier
 * 🇺🇸 Ellie Douglas
 * 🇺🇸 Victoria Duval
 * 🇪🇸 Paola Expósito Díaz Delgado

The following player received entry using a protected ranking:
 * 🇺🇸 Louisa Chirico

The following player received entry as a special exempt:
 * 🇺🇸 Kayla Day

The following players received entry from the qualifying draw:
 * 🇦🇺 Alexandra Bozovic
 * 🇺🇸 Sophie Chang
 * 🇺🇸 Jada Hart
 * 🇯🇵 Haruka Kaji
 * 🇷🇺 Maria Kozyreva
 * 🇯🇵 Hiroko Kuwata
 * 🇺🇸 Maegan Manasse
 * 🇺🇸 Emma Navarro

Singles

 * 🇺🇸 Usue Maitane Arconada def. 🇲🇽 Marcela Zacarías, 6–1, 6–3

Doubles

 * 🇺🇸 Sophie Chang / 🇺🇸 Angela Kulikovdef. Liang En-shuo / 🇨🇳 Lu Jiajing, 6–4, 6–3