Chung, who turns 31 in August, was referred to by Bill Belichick this past season as one of the best players in the NFL and is valued for his toughness and versatility. He was scheduled to earn $2 million this season and have a salary-cap charge of $3.8 million.
The Patriots have some top players set for free agency in 2019, a group headlined by receivers Brandin Cooks, defensive end Trey Flowers and starting right guard Shaq Mason. Now they can take Chung -- who played 87.5 percent of the defensive snaps last season -- off the list.
The NFL Network first reported that Chung was expected to sign an extension with the Patriots.