The 2021 Astana Open was a tennis tournament organized for professional tennis players, held in Nur-Sultan, Kazakhstan, in 2021 on indoor hard courts. It was primarily organized due to the cancellation of many tournaments during the 2021 ATP Tour and 2021 WTA Tour, because of the ongoing COVID-19 pandemic. It is the second edition of the tournament for the men and the first for the women. The tournament took place in Nur-Sultan, Kazakhstan, from 20–26 September for the men, and from 27 September to 2 October for the women.