Great Britain confirmed five quota places in the triathlon events for Tokyo. British Triathlon announced the athletes to occupy four of those places on 4 November 2020, including returning medallists Jonathan Brownlee and Vicky Holland. Reigning double Olympic champion Alistair Brownlee was not confirmed in the fifth and final quota place, which remains to be filled. On 14 June 2021, Team GB announced that Alex Yee had been selected to fill the remaining place on the British triathlon squad for Tokyo.
