The 2021 Rachael Heyhoe Flint Trophy was the second edition of the Rachael Heyhoe Flint Trophy, an English women's cricket 50-over domestic competition, which took place between 29 May and 25 September 2021. It featured eight teams playing in a round-robin group, followed by a knock-out round. The holders were the Southern Vipers, who won the inaugural competition in 2020. It ran alongside the Charlotte Edwards Cup. The tournament was named after former England captain Rachael Heyhoe Flint, Baroness Heyhoe-Flint, who died in 2017.