The 33-year-old Suh started all 16 games for the Buccaneers last year and has started every game of his 10-year career outside of a two-game suspension in 2011.
Suh's new deal is a pay cut for the veteran tackle, as he signed a one-year, $9.25 million contract with the club last offseason.
The Nebraska product is a five-time Pro Bowler, but he has to failed to make the Pro Bowl since 2016. Suh has not been first-team All-Pro since 2014.
The NFL's sack leader in 2019, Shaq Barrett, is returning to Tampa Bay after being given the franchise tag, while veteran linebacker Jason Pierre-Paul re-signed with the club on a a two-year deal.
The Buccaneers also added six-time Super Bowl winner Tom Brady at the start of free agency.
Tampa Bay's defense ranked 29th overall last season, but it was first in terms of fewest yards allowed on the ground.
Analysis from SI team channel AllBucs: Bringing Suh back completes one of Tampa Bay's most important missions for this offseason, as they keep one of the NFL's best front-seven groups in tact. The entire defense made huge improvements over the second half of last season, and Suh was a big part of the league's top-ranked rushing defense. His veteran presence in the locker room can't be overstated, either, especially with the defense relying on so many young players. Defensive coordinator Todd Bowles will have the band back together in 2020, and Suh will be a key part of building on last year's success. —Luke Easterling