Stewart was born in Edinburgh but raised in Rutherglen, South Lanarkshire where he attended Stonelaw High School.
[3] He initially began his career as a midfielder but retrained as a full-back, which he stated drew more scrutiny on his performances from his father, who had played the same position.
[4] After three seasons as a squad member, he became a regular starter for the Diamonds in the 2016–17 campaign, going on to make over 100 appearances over the next three years,[1][5] including a promotion playoff semi-final defeat to Alloa Athletic on penalties in 2017[6] (the closest Airdrie came to either being promoted or relegated in his time with the club) and a Scottish Cup visit to holders Celtic in 2019.
[11] He made his debut for the club on 23 July 2019, in a 3–0 defeat away to Hibernian in the group stage of the 2019–20 Scottish League Cup.
[12] He was an important member of the Red Lichties team in their bid for promotion to the Scottish Premiership in the 2021–22 season, while also working as a P.E.