"There will be a lot of discussions, but now is not the time for that."
Roethlisberger, 38, completed 47 of 68 passes for 501 yards, four scores and four interceptions in the 48-37 setback on Sunday in Pittsburgh. The six-time Pro Bowl selection completed 65.6% of his throws for 3,803 yards, 33 scores and 10 interceptions in 15 starts this season.
The Steelers began the season with an 11-0 record before they lost five of their final six games. Roethlisberger threw 12 touchdown passes and eight interceptions over his final five starts.
"[The decision to retire] starts with me and God and a lot of praying," Roethlisberger said. "There will be a lot of talking with my family."
Roethlisberger signed a two-year contract extension in 2019 and is tied to the team through the 2021 season.
The two-time Super Bowl champion ranks No. 7 all-time in career passing yards and No. 8 in touchdown passes. The 17-year veteran ranks No. 4 on the all-time wins list, with 169 career victories as a starter in the regular season and postseason.