Her brother, Hadden Frost, is a former jockey who won numerous races including the Pertemps Final at the Cheltenham Festival on Buena Vista in 2010.
She turned professional in July 2017 and later that month secured her first win as a conditional jockey on the Nicholls-trained Black Corton at Worcester.
In November 2017, Frost rode the Nicholls-trained Present Man to win the Badger Beer Handicap Chase at Wincanton.
[6] The following month she rode the Nicholls-trained Frodon to victory in the Grade 3 Crest Nicholson Handicap Chase at Cheltenham in January 2018.
[10] In March 2019 she became the first woman to win a Grade 1 race at the Cheltenham Festival when Frodon carried her to victory in the Ryanair Chase.
[12] Frodon was beaten into fourth place when attempting to secure back-to-back wins in the Ryanair Chase at the 2020 Cheltenham Festival.
[13] In December 2020, Frost rode Frodon to victory in the King George VI Chase at Kempton, becoming the first female jockey to win the race.
[21] In September 2020, Frost lodged a complaint with the British Horseracing Authority (BHA) about bullying and harassment by jockey Robbie Dunne.