Reardon is a member of Blackheath & Bromley Athletic Club. He won gold at the Under-17 men’s 800m race at the national indoor championships in February 2020.[5]
In February 2023 Reardon ran 46.96 over 400 metres to win his first national championship gold medal at the 2023 British Indoor Athletics Championships.[9][10][11] He was subsequently selected for the Great Britain squad for the European Indoor Championships held in Istanbul from March 2, 2023.[12] He was selected for the England team to take place at the Loughborough International in May 2023.[13]
He was selected as part of the Great Britain team for the 2023 European Athletics U23 Championships held from in July 2023 in Espoo, Finland.[14] He ran a new personal best time of 1:45.95 to reach the 800m final.[15] He also made his debut at a Diamond League event, in London in July 2023.[16]
2024
In January 2024, he pulled a hamstring which kept him out of competitive action for a number of months and could not take part in the British Olympic trials.[17] In July 2024, he ran 45.99 seconds for the 400 metres at the Morton Games in Dublin.[18] He lowered his personal best for the 400 metres to 44.70 seconds at the London Athletics Meet on 20 July 2024.[19] Reardon was called-up as a late replacement for the Great Britain 4x400 metres relay squad for the 2024 Summer Olympics following the withdrawal of Charlie Carvell due to a hamstring injury.[20] He was part of the mixed 4x400 team which won a bronze medal in a new national record of 3:08.01.[21][22] He also competed in the men's 4x400m relay at the Games, winning a second bronze medal.[23]
