He is the younger brother of England international and Biarritz player Jonathan Joseph.
Career
Joseph was educated at Millfield. At the age of thirteen he joined the academy of London Irish and made his club debut in 2021. He scored a try in the semi-final of the 2021–22 Premiership Rugby Cup against Leicester Tigers and then started in the final as they finished runners up to Worcester Warriors.
Joseph played for the England under-18 team. He represented the England under-20 team during the 2022 Six Nations Under 20s Championship.
In May 2022 Joseph received his first call-up to the senior England squad by coach Eddie Jones for their tour of Australia. On 9 July 2022 he made his senior debut for England as a late substitute during their second test victory at Lang Park. He was an unused substitute for the final game as they beat Australia at Sydney Cricket Ground to win the series.
In May 2023, Joseph initially made Steve Borthwick's 38 man World Cup training squad ahead of the 2023 Rugby World Cup to be contested in France. He was ultimately cut from the squad the following month, alongside Beno Obano as Borthwick shrunk his squad to 36 players.
In June 2023, following the collapse of his domestic club London Irish, Joseph signed for Harlequins. He made his debut in the Premiership Cup against Gloucester Rugby scoring a try in the 39th minute.
In February 2025, it was announced that Joseph would join Premiership rivals Gloucester ahead of the 2025-26 season.
In November 2026, Joseph won his second cap for England during the 5th round of the World Rugby Nations Championship against Japan. He scored 5 tries in the game.
