According to Sportsnet's Elliotte Friedman, the deal has an average annual value of $2.66 million.
Forsling, 25, registered five goals and 17 points in 43 regular season games during the 2020-21 campaign, plus he added one goal and one assist during the Panthers' first-round series against the Tampa Bay Lightning.
The Swedish defenceman set career-highs in games played, goals, points, assists (12), plus-minus rating (plus-17) and shots (94) this season. Over 165 career NHL games with the Panthers and Chicago Blackhawks, Forsling has recorded 13 goals and 44 points.
He was originally selected by the Vancouver Canucks in the fifth round of the 2014 NHL Draft, 126th overall.