Born in Stourbridge, Bellingham joined Blues as an Under-8 in pre-Academy and has been in the youth system ever since.
He made his Under-18s debut aged 14 and broke into the Under-23s in March 2019, coming on and scoring the winner at Nottingham Forest at the City Ground.
Bellingham made 12 appearances for the Under-23s during the 2018/19 season - six starts, six as substitute - and scored on three occasions.
A gifted, intelligent footballer, Bellingham can play in a variety of positions, most notably as a 10 or eight.
On 6 August 2019, Bellingham became the youngest player to feature in the first team at the age of just 16 years and 38 days
At the tender age of just 16 years and 38 days, Bellingham made his senior debut for Blues in the EFL Cup first round tie against Portsmouthon 6 August 2019.
In doing so he bettered a mark that had stood for 49 years.
Blues legend Trevor Francis made his Blues debut as a substitute against Cardiff City in September, 1970 at 16 years and 139 days.