[1] In August 2023, Colwill made his senior debut for Cardiff City in the EFL Cup against Colchester United.
[3] On 2 August 2024, Colwill joined League Two club Cheltenham Town on an initial season-long loan deal.
[4] Having impressed over the first-half of the season, it was announced on 10 January 2025 that Colwill would be recalled from his loan at Cheltenham.
[5] On 12 January 2025, Colwill was signed by League One club Exeter City on loan until the end of the season.
[6] Joel Colwill made his Wales Under-21 debut on 8 September 2023 in the 4-0 friendly win against Liechtenstein alongside his brother Rubin.