In the 2008–09 season, Smith signed an entry-level contract with the Ottawa Senators[3] and attended the team's training camp.

Smith missed most of the 2014–15 season due to dislocating a wrist after a collision with the Boston Bruins' Brad Marchand on December 13, 2014.

[8] Smith's performance drastically improved during the 2015–16 season, where he appeared in 81 games and achieved career highs in goals (25) and points (36).

He was scoreless in his first 10 games with Chicago before collecting two assists on goals by Kirby Dach and Calvin de Haan against the Vegas Golden Knights on November 13.

Smith made 50 appearances with the Blackhawks, posting four goals and 11 points, before suffering a cut from a skate blade to his hand against the Vancouver Canucks on February 12, 2020.

It was later announced that Smith would miss the remainder of the season, due to a back injury requiring surgery on March 6.