McCallum was obtained in June 1901 from Queen's Park, Scotland's oldest association football club, founded in 1867. Liverpool's regular right-back in the 1902/03 season was John Glover and he missed only four of the 34 first division fixtures during that campaign. On two of those occasions, McCallum stepped in to cover for him, in a 2-1 win over West Bromwich Albion on 11 October 1902 and a 3-1 defeat to Blackburn Rovers on 3 January 1903. He moved to Morton in Greenock, Scotland prior to the 1903/04 season in exchange for Herbert Craik. Following spells with Sunderland and Middlesbrough in the First Division he moved back to Scotland eventually joining Lochgelly United before moving on to their greatest rivals, East Fife, where he spent two seasons, with one year in Wales with Mid Rhondda squeezed in between.