Freeman, 31, was suspended 10 games last season for a second violation of the league's policy on performance-enhancing substances.
The Bears have also declined to pick up the $8 million 2018 option on Pro Bowl offensive lineman Josh Sitton, according to multiple reports.
The 31-year-old Sitton, who missed the final two games of the 2017 season with an ankle injury, told the Chicago Tribune that he has "prime years left," and intends to play next season.
Like Sitton, Freeman also battled injuries in 2017. The Bears placed Freeman on injured reserve in Week 2 after the veteran tore a pectoral muscle in the season opener versus Atlanta. Freeman suggested that the concussion he suffered in the Falcons game contributed to the latest suspension.
Freeman -- voted a team captain before Week 1 -- missed four games in 2016 for his first violation of the PED policy, but still finished with a team-high 110 tackles.
He played four seasons in Indianapolis, registering at least 100 tackles three times, before he signed a three-year deal with Chicago in 2016.
Freeman was scheduled to earn $3.5 million in 2018, but none of it was guaranteed.
ESPN's Jeff Dickerson contributed to this report.