[18] In the event finals, Tinkler won the bronze medal on the vault behind gold medalist and teammate Ellie Downie.

[19] Tinkler also qualified for the floor exercise final, where she tied for second place with Romanian Andreea Iridon behind teammate Catherine Lyons with 13.966.

At the beginning of March, Tinkler made her senior debut at the English National Championships, at the Sir David Wallace Hall in Loughborough.

[24] In the all-around final she became the British champion and like in the English Championships, the winner from 2014, Rebecca Tunney didn't attend this competition.

13.650 on the uneven bars, 13.750 on the balance beam and 14.400 on the floor exercise to improve on the English Championships result of 56.200 to end with a total of 56.650.

[29] Tinkler competed at the 6th Men's and Women's European Championships on 15 April, in the all-around qualifications she scored 14.625 on the vault, 13.300 on the uneven bars, 12.833 on the balance beam and 14.200 on the floor exercise, for a total of 54.958 and finishing in 6th place.

[30] Although she did qualify in third place for the floor exercise final behind 2014 European bronze medalist Giulia Steingruber and 2011 world champion, Ksenia Afanasyeva.

[32] In September, Tinkler competed at the British Team Championships, where she helped the South Durham Gymnastics Club finish in fourth place[33] contributing 14.300 on the vault, 13.600 on the uneven bars, 13.200 on the balance beam and 13.600 on the floor exercise, also making her first all-around in the competition.

[40] Tinkler won the bronze medal in the floor exercise with a score of 14.933, finishing behind Americans Simone Biles and Aly Raisman.

In April, Tinkler competed at the London World Cup, coming in third behind Tabea Alt of Germany and Victoria Nguyen of the United States.

In September, Tinkler was named to the team for the World Championships in Montreal, along with Georgia-Mae Fenton, Claudia Fragapane and Alice Kinsella.

[51] In February, Tinkler was named to the England team for the Commonwealth Games in the Gold Coast, alongside Georgia-Mae Fenton, Claudia Fragapane, Alice Kinsella and Kelly Simm.

[43] On 26 January 2021, it was announced that Tinkler would be a contestant on the thirteenth series of Dancing on Ice, partnered with Joe Johnson.

Tinkler made her debut in the competition in week 3, replacing Denise van Outen who was forced to withdraw from the show due to injury.