The deal carries an average annual value of $9.85 million and will kick in for the 2019-20 season.
Seguin has one more year on his current contract at $5.75 million. His new deal makes him the highest paid player on the Stars, surpassing captain Jamie Benn's $9.5-million yearly wage.
On a league-wide scale, the 26-year-old is set to be one of the highest-paid centers in the league, as only six pivots currently earn $9 million or more per season.
Seguin's contract saga has been one of the recurring themes of the offseason since he said he was disappointed in a lack of discussions in late August. After voicing his displeasure, the Stars made it clear they intended to work out a deal before puck drop in October.
"I'm thrilled to have this signed going into the season," said Seguin, per the team's website. "Dallas has become home to me and I love this organization. In my time over the last five years with Tom Gaglardi and Jim Nill, it is clear how bad they want to win and have a model franchise. To be a part of that leadership group for the next nine seasons is an honor, and I can't wait to get this season started with my teammates."
Since joining Dallas via trade prior to the 2013-14 season, Seguin has been one of the league's premier producers. Over five seasons, he's amassed 384 points in 387 games, and his 173 goals trail only Alex Ovechkin over that span.