The deal is similar to Slater's previous contract, a two-year deal that averaged $2.6 million per year.
Slater, who turns 35 in September, has been the Patriots' special-teams captain every year since 2011. The eight-time Pro Bowl selection is an inspirational and spiritual leader. Coach Bill Belichick has him address players and coaches after every victory.
The son of Pro Football Hall of Fame offensive lineman Jackie Slater, Matthew Slater surpassed Steve Tasker for most special-teams Pro Bowl honors in NFL history. He has led the Patriots in special-teams tackles in seven of his 12 seasons.
The 2008 fifth-round draft choice out of UCLA has one career NFL reception for 46 yards. Although he is listed on the roster as a wide receiver, he is seldom used at that position and is usually only a blocker in short-yardage situations.