Calum Macleod started his cricket career as a dashing fast bowler who soon had to reinvent himself as a batsman in a bid to sustain. Macleod was reported for his bowling action by the umpires after an Intercontinental Cup game against Canada in July 2010, where he picked 6 wickets. Despite working with Allan Donald, who was coaching Macleod's club Warwickshire at the time, nothing substantial was achieved and as a result, he was released by the club at the end of that season.

Calum MacLeod featured in the 2006 Under-19 Cricket World Cup for Scotland. He also made 70 appearances for Scotland in age-group matches. In November 2007, the 19-year-old MacLeod signed a two-year contract with Warwickshire. In the same year, he gained his full First-Class Scotland cap when he was called up for the Intercontinental Cup match against the UAE, becoming the youngest Scottish player to debut at that level.

In the 2012 T20 World Cup Qualifier match against Oman, MacLeod scored 104 off just 76 balls, helping Scotland secure a thumping win. With 307 runs from nine matches (including one century and two fifties), he was Scotland's leading run-scorer in the tournament.

In one of the World Cup Qualifier games in 2014, MacLeod smashed 175, the second-highest score by an Associate player in an ODI and third-highest by an Associate player in List A cricket, in Scotland's 170-run thrashing of Canada. This performance helped his side seal a place in the Super Sixes. He was the third highest run-getter in the Qualifiers, amassing 401 runs in eight games.

Macleod, an established top-order batsman in the year 2018, had his share of fame in the one-off ODI against bigwigs England, when he cracked an unbeaten 140 off 94 balls at the Grange Cricket Club, Edinburgh, helping his side post an imposing 371 against the No.1 ranked England side.