Born in
Regina, Saskatchewan in family with
Ukrainian roots, Klimchuk grew up in
Calgary,
Alberta, and played his
minor hockey in the Calgary Buffaloes system. He was the
captain of his team in the
Alberta Major Bantam Hockey League in 2009–10 and led his squad to the final of the Western Canadian Bantam championship, ultimately settling for second place. The
Western Hockey League (WHL)'s
Regina Pats selected him in the first round, fifth overall, at the 2010 WHL Bantam Draft, and he appeared in five games with the Pats in
2010–11. Klimchuk joined the Pats full-time in
2011–12. He played in 67 games, and his 36 points helped Regina reach the WHL playoffs for the first time since 2008. He was a member of Team Pacific at the
2012 World U-17 Hockey Challenge, finishing second in team scoring with six points in six games, and played with Team Alberta at the 2011
Canada Winter Games. He made two appearances with the
Canadian national under-18 team. He was a member of the gold medal-winning Canadian team at the
2012 Ivan Hlinka Memorial Tournament. Playing on the
top line with
Sam Reinhart and
Connor McDavid, Klimchuk scored eight points to help lead Canada to a gold medal at the
2013 IIHF World U18 Championships. The
Calgary Flames used the pick they acquired in the
Jarome Iginla trade to select Klimchuk in the first round, 28th overall. He signed a three-year entry-level contract with the Flames on December 17, 2013. On January 2, 2015, Klimchuk was dealt from the Pats to the
Brandon Wheat Kings, in a trade that saw Jesse Gabrielle move to the Pats. Klimchuk was invited to the Flames' 2015 training camp, but was assigned to the Flames
American Hockey League (AHL) affiliate, the
Stockton Heat for the
2015–16 season. Klimchuk made his NHL debut on February 19, 2018, against the
Boston Bruins. The following day he was reassigned to the AHL. During the
2018–19 season, on November 27, 2018, Klimchuk was traded by the Flames to the
Toronto Maple Leafs in exchange for
Andrew Nielsen. Klimchuk appeared in just 13 games with the
Toronto Marlies, before he was traded by the Maple Leafs for the second time within the season to the
Ottawa Senators in exchange for
Gabriel Gagne on January 11, 2019. He finished the season with Ottawa's AHL affiliate, the
Belleville Senators scoring four goals and five points in eight games before a season-ending shoulder injury. The Senators re-signed Klimchuk to a one-year two-way contract on June 13, 2019. He spent the entire
2019–20 season with Belleville. ==Coaching career==