She won gold at the 2020 Tokyo Olympics in mixed 4 × 100 metre medley relay in a world record time.

She represented Great Britain at the 2016 European Aquatics Championships, and won a bronze medal in 100 metre backstroke.

[6] At the Tokyo Olympics, Dawson raced in the backstroke lead-off leg of the final of the mixed 4 × 100 metre medley relay, winning gold and setting a world record time of 3 minutes 37.58 seconds together with Adam Peaty, James Guy and Anna Hopkin.

Dawson was appointed Member of the Order of the British Empire (MBE) in the 2022 New Year Honours for services to swimming and women in sport.

[8][9] After winning the 100 metres backstroke at the 2024 Aquatics GB Swimming Championships, Dawson sealed her place at the 2024 Summer Olympics.