The 21-year-old forward, who was a restricted free agent, was training with SC Bern in Switzerland. He missed Jets training camp and five preseason games.
"Any negotiation, like I've always said, it takes its own life with some twists and some turns," Winnipeg general manager Kevin Cheveldayoff said. "Again, it's about getting to the destination, and we're excited that we were able to agree to terms today."
Laine had 50 points (30 goals, 20 assists) in 82 games last season, the fewest in his three-season NHL career. He scored 44 goals in 2017-18 and 36 in 2016-17, and his 110 goals during those three seasons are sixth in the NHL.
"We're dealing with an elite player here," Cheveldayoff said. "If you look at his stats, what he's accomplished at 18, 19 and 20 years old, there's not many players that have done that. Again, that's the uniqueness of the situation here.
"That's what makes it most exciting for us with Patrik, that I think we're just starting to scratch the surface of what he actually brings to the table here. We've got an opportunity here to see it all unfold in front of our eyes. We're a team that's growing, a team that's maturing."
Laine scored 18 goals in 12 games during November but scored nine in his remaining 58 games last season, including one in the final 19 games. He had four points (three goals, one assist) in six Stanley Cup Playoff games.
Selected with the No. 2 pick in the 2016 NHL Draft, Laine has 184 points (110 goals, 74 assists) in 237 regular-season games and 16 points (eight goals, eight assists) in 23 playoff games.
Jets forward Kyle Connor remains a restricted free agent with Winnipeg about to open the NHL regular season Oct. 3 at the New York Rangers. It then plays Oct. 4 at the New Jersey Devils and Oct. 6 at the New York Islanders.
"We had to make some tough decisions this year," Cheveldayoff said. "You're dealing with [an NHL salary cap] that's a hard one, and sometimes you have to make those tough decisions. We were trying to find a number that would work for both sides and keep as much of the team together as possible."
NHL.com staff writer Tim Campbell contributed to this report
