2021 In 2021, at the age of 19, Jarman finished tenth in the all-around at the
European Championships, the
individual all-around, with England teammate
James Hall in second place, the floor final with teammate
Giarnni Regini-Moran in bronze, and the vault final with Regini-Moran in silver. Jarman then competed for Great Britain at the
2022 European Championships, where he helped Great Britain win the team final for the first time in a decade, and only the second time ever. Additionally, he finished 8th in the individual all-around and qualified for the floor final, but initially missed the vault final on the two-per-nation rule despite qualifying in fifth. On individual finals day Jarman won bronze on
floor before the withdrawal of teammate
Giarnni Regini-Moran from the vault final to concentrate on parallel bars allowed Jarman to take part in that final. Taking advantage, Jarman won gold in the
vault final, edging out Armenian rival
Artur Davtyan on tie-break.
2023 During the
2023 World Challenge Cup Series, Jarman became the first gymnast to perform a 3.5 twisting double layout salto on floor exercise, getting the skill named after him in the Code of Points. He then was part of the British team that represented Great Britain at the
2023 World Championships, where the British team placed fourth, and individually, Jarman made the all-around final and won the gold medal in the vault final. In doing so he became the first Briton to win world gold on the apparatus, the fourth male British World Champion (after
Max Whitlock,
Joe Fraser, and
Giarnni Regini-Moran), and sixth British World Champion in artistic gymnastics (after Whitlock, Fraser, Regini-Moran,
Beth Tweddle, and
Jessica Gadirova).
2024 At the
2024 European Championships Jarman helped Great Britain finish second as a team behind Ukraine. Individually he won his second gold medal on vault. In June of that year Jarman was selected to represent
Great Britain at the 2024 Summer Olympics alongside
Joe Fraser,
Harry Hepworth,
Luke Whitehouse, and
Max Whitlock. Paris was Jarman's Olympic debut and with his teammates, finished fourth at the
team all-around. He qualified for the finals of the
floor exercise with the highest score of 14.966 and ultimately won bronze medal with a score of 14.933, his career-first Olympic medal and Team GB's first Paris medal in artistic gymnastics. During the Paris Olympics, it was reported in Philippine news media that the
Gymnastics Association of the Philippines (GAP) is recruiting Jarman to potentially represent the country at the
2028 Summer Olympics in Los Angeles, with GAP president
Cynthia Carrion stating that "[Jarman] wants to play for the Philippines".
2025 Jarman was selected to attend the
2025 European Championships alongside
Harry Hepworth,
Jamie Lewis,
Jonas Rushworth and
Luke Whitehouse where he contributed on floor exercise, vault, pommel horse, parallel bar and high bar to help Britain win their third ever European team title. He also qualified for the vault and mixed team final. He won silver with
Ruby Evans in the inaugural mixed team final and won silver on vault. In late September Jarman was selected to represent Great Britain at the
2025 World Championships where he won gold on floor exercise. ==Eponymous skill==