Fright Fest at Six Flags in 2025 generally starts in mid-September, but the exact start date varies slightly by park:

• Six Flags Great Adventure (New Jersey) starts on Friday, September 12, 2025, running select nights through November 2, 2025.

• Six Flags Great America (Illinois) runs from September 13 to November 2, 2025.

• Six Flags Darien Lake runs select nights from September 21 to October 26, 2025.

• Six Flags St. Louis starts September 13 through November 2, 2025.

• Six Flags Magic Mountain (California) runs select nights from September 19 to November 2, 2025.

In general, Fright Fest usually begins in the second week of September and runs through early November at most Six Flags parks with nighttime scare attractions, haunted mazes, and themed shows included. The schedule each year can vary slightly by location and park. The nighttime scares and haunted houses typically begin in the evening, around 6 p.m.

If there is a specific Six Flags park of interest, I can provide the exact start date for that location.