The Senators' 2015 first-round draft pick (18th overall) was an All-Star in 2018-19 with 14 goals and 41 assists in 70 games. His 55 points ranked 10th among NHL defensemen.
"Thomas is an exceptional talent and an outstanding teammate, who is impactful both on and off the ice. He is the type of player that can develop into a core member of a championship-level team in the National Hockey League," Senators general manager Pierre Dorion said in a release.
Chabot has tallied 23 goals and 80 points in 134 career games.
The extension begins after his entry-level contract expires at the end of the 2019-20 season and runs through the 2027-28 campaign.
--Field Level Media