Harrison signed for Edinburgh academy in June 2020.

[2] He made his Pro14 debut in the rearranged Round 7 of the 2020–21 Pro14 against the Dragons, coming on as a replacement.

[3] He joined London Irish on a short-term loan on the 20 September 2022.

[4] In June 2024 Harrison was called up to the senior Scotland squad for a tour of The Americas.

This Scottish rugby union biography article is a stub.