The American version of Big Brother Season 27 premiered on July 10, 2025. New episodes air three times a week on CBS: Sundays, Wednesdays, and Thursdays at 8 p.m. ET/PT. Wednesday episodes are 90 minutes long, while Sunday and Thursday episodes are one hour each. There is also a companion show, Big Brother: Unlocked, airing every other Friday at 8 p.m. ET on CBS and Paramount+.
For 2025, the season is expected to conclude around late September or early October, with the finale likely airing near the end of September.
So, generally, Big Brother comes on at 8 p.m. ET/PT on Sundays, Wednesdays, and Thursdays.
