The Tigers announced the decision on Sunday. They begin the season on Thursday at Toronto.
Zimmermann has struggled during his three years with the Tigers after arriving as a free agent before the 2016 season.
He battled neck issues in 2016 before going 8-13 with a 6.08 ERA in 29 starts in 2017.
Last year, the 32-year-old Zimmerman was 7-8 with a 4.52 ERA over 25 starts and had core muscles repair surgery in October.