Smith, played midget originally with CAC Edmonton Canadians of the Alberta Midget Hockey League. In the 2008–09 season Smith joined the Western Hockey League after he was drafted 7th overall in the WHL Bantam draft in 2008 by the Kamloops Blazers. As a centre with average size, Smith developed a high hockey sense in his four-year outstanding career. He was awarded the Doc Seaman Memorial Trophy when he was only 17 years old, a coveted trophy given to the Western Hockey League's Scholastic Player of the Year. In 2011, he played in the Under-18 World Championship in Germany representing Canada. "The entire Kamloops Blazers organization is very proud of Colin Smith for earning this award," remarked Craig Bonner, Vice-President and General Manager to Kamloops Blazers. Smith happens to be the third player to win this award for the Blazers. Smith added another feather to his cap, when he was selected by the Colorado Avalanche, becoming the fifth Blazer drafted by the Avalanche, and the first since Ray Macias in 2005. In his final year with the Blazers in the 2012–13 season, Smith was a contender throughout the season to be the WHL's leading scorer. Alongside linemate J.C. Lipon, Smith helped the Blazers set a franchise record in consecutive wins whilst earning consideration for the Canadian World Junior Squad. Smith finished fourth overall in league scoring with 106 points in 72 games and was rewarded for his outstanding performance with a selection to the 2013 WHL West First All-Star Team.
Professional
On July 5, 2013, it was officially announced that Smith had signed a three-year entry level contract with the Colorado Avalanche. After attending the Avalanche's training camp and taking part in his first pre-season, Smith was assigned to AHL affiliate, the Lake Erie Monsters for the 2013–14 season. He made his professional debut against the Abbotsford Heat in the season opener before Smith enjoying a successful rookie campaign in finishing as the only Monster to play in each game, and led the team amongst rookies with 34 points in 76 games. During his second season with the Monsters in 2014–15, Smith received his first NHL recall by the injury stricken Avalanche on November 30, 2014. On December 1, 2014, he made his NHL debut, as a centre on the fourth line, in a 4–3 defeat to the Montreal Canadiens before he was re-assigned to the Monsters the following day for the remainder of the year. In the last year of his entry-level contract, Smith was re-assigned to begin the 2015–16 season with new AHL affiliate, the San Antonio Rampage. Smith emerged amongst the top scorers with the Rampage and placed third with 34 points in 54 contests before he was traded by the Avalanche, along with a fourth round pick in the 2016 draft, to the Toronto Maple Leafs in exchange for Shawn Matthias on February 21, 2016. Smith was immediately assigned to Toronto's AHL affiliate, the Toronto Marlies. Despite not being tendered a qualifying offer in the off-season by the Maple Leafs, Smith opted to remain in the organization in agreeing to a one-year AHL contract with the Marlies on July 3, 2016. In the 2016–17 season, Smith was unable to retain his initial scoring rate from the last season with the Marlies. Collecting 28 points in 52 games, Smith was returned to the San Antonio Rampage in a trade in which the Marlies secured Mike Sisloon loan on March 1, 2017. In his second stint with the Rampage, Smith was entrenched on the top 2 scoring lines to finish with 19 points in 21 games. As a free agent in the off-season, Smith continued his career in the AHL by securing a one-year contract with the Wilkes-Barre/Scranton Penguins on July 6, 2017. In the 2017–18 season, Smith suffered an early injury however returned to play in 35 games with the Penguins, recording 18 points. On February 14, 2018, Smith was traded by Wilkes-Barre/Scranton in exchange for Joseph Cramarossa to the Stockton Heat, affiliate to the Calgary Flames. In 24 games to end the regular season, Smith continued his offensive output in compiling 17 points. At the conclusion of the season, Smith opted to leave North America as a free agent, agreeing to a one-year contract with German outfit, Eisbären Berlin of the DEL on June 28, 2018. Smith had difficulty adjusting in his first European season with Berlin in 2018–19, posting just 4 goals and 23 points in 52 games. Smith opted to continue in the DEL with a point to prove, signing a one-year deal with ERC Ingolstadt on July 19, 2019. He opened the 2019–20 season, collecting 3 goals and 8 points in 17 games with Ingolstadt before leaving the club to join Kölner Haie for the remainder of the season on November 21, 2019.
