Big Brother Season 27 airs new episodes on CBS on Sundays, Wednesdays, and Thursdays at 8:00 PM Eastern Time. Wednesday episodes are 90 minutes long, while Sunday and Thursday episodes run for 60 minutes. There are also special "Big Brother: Unlocked" episodes airing every other Friday at 8:00 PM ET. The season premiered on July 10, 2025, and is scheduled to conclude with the finale on Sunday, September 28, 2025.