[4] Aged 18 he made his first team debut[5] on 20 August 2014, in the second round of the Scottish Challenge Cup away to Livingston, playing from the start in a 4–1 loss.
[8] He made his league debut on 30 August 2014, against East Stirlingshire in a 3–1 win,[9] with his first goal coming against Queen's Park on 20 September salvaging a 2–2 draw.
[7] On his return to Hearts Smith made his Scottish Premiership debut on 18 October, coming on as a 71st-minute substitute against Dundee United at Tannadice Park, replacing Juwon Oshaniwa in a 1–0 win.
[15] It proved to be a successful loan spell as Saints won the Scottish Championship, with Smith playing 34 games and scoring twice.
[17] On 16 April 2019, Dundee United confirmed that Smith had signed a pre-contract to join the club in the summer, agreeing a two-year deal.