[1] After returning from a loan spell with Brora Mackinnon made his league debut for County on 26 February 2022 in a 3–1 win against St Johnstone coming on for Harry Paton in the 90th minute.
[2] On 20 November 2020 Mackinnon joined Highland Football League side Brora Rangers ahead of the new season.
[6] On 7 October 2023 Mackinnon was loaned to Highland League side Brora Rangers till the end of the 23/24 season.
[7] In January 2024, Mackinnon joined Scottish Championship club Arbroath on loan until the end of the season.
[8] In August 2024, Mackinnon joined Scottish League One club Inverness Caledonian Thistle on a 2 Year Contract.