Hopkin was named as a member of the British team to go to the postponed 2020 Olympics in Tokyo. This would be her first Olympics and she joined as part of what was considered a "high quality" swimming team. Hopkin swam the anchor freestyle leg in the Mixed 4 x 100 metre medley relay, and won gold in a new world record time of 3 minutes 37.58 seconds together with Adam Peaty, James Guy and Kathleen Dawson.