Colin Smith was born June 20, 1993 in Edmonton Alberta. A product of the Kamloops Blazers of the Western Hockey League, where he starred for four season, he was selected by the Colorado Avalanche in the seventh round of the 2012 NHL Entry Draft.
Smith was assigned to Avalanche's AHL affiliate, the Lake Erie Monsters, to start the 2013–14 season and had a successful rookie campaign, finishing with 34 points in 76 games.
During his second season with the Monsters in 2014–15, Smith received his first NHL recall. He made his NHL debut on December 1, 2014 in a 4-3 defeat to the Montreal Canadiens before he was re-assigned to the Monsters the following day.
On February 21, 2016, Smith's time in the Avalanche organization would come to an end. He was traded along with a fourth round draft pick to the Toronto Maple Leafs in exchange for Shawn Matthias. He was then assigned to Toronto's AHL affiliate, the Toronto Marlies for the remainder of the season.