There are two main versions of Big Brother starting in 2025:
- The American version, Big Brother Season 27, started on CBS on July 10, 2025. It airs three times a week on Wednesdays, Thursdays, and Sundays, with episodes at 8 pm ET/PT. The season will run until September 28, 2025.
- The British version, Big Brother 22, is set to begin airing in September 2025 on ITV2. This will be the longest series on ITV, co-presented by AJ Odudu and Will Best.
If asking about a specific country's Big Brother start date, the American version is already underway from July, while the next UK series will begin in September 2025.
