The Canadiens receive defenceman Justin Barron and a 2024 second-round pick. Montreal will retain 50 per cent of Lehkonen's salary.
Lehkonen, 26, has 13 goals and 16 assists for 29 points in 58 games this season. Third on the Habs in points, Lehkonen is also fourth in assists and tied for third in goals. He is two points shy of matching a career-high 31 points, set over 82 games in 2018-19.
Lehkonen has 149 points (74 goals, 75 assists) in 396 career NHL games, all with the Canadiens, who selected him in the second round (55th overall) in 2013.