Carlsson, a defenseman, was selected by the Columbus Blue Jackets with the No. 29 pick in the 2015 NHL Draft. He played three seasons in the Swedish Hockey League before signing a three-year contract with Columbus on April 19, 2016.
Carlsson made his NHL debut against the Philadelphia Flyers on April 8 and earned his first NHL point, an assist, the next day in a 3-2 win against the Toronto Maple Leafs. He split the 2017-18 season with the Blue Jackets (two assists in 14 games) and Cleveland of the American Hockey League (five points; two goals, three assists in 33 games).