A list of events that occurred on September 15 related to Six Flags.
- 2018 – Fright Fest 2018 begins at Six Flags Great Adventure.
- 2018 – Fright Fest 2018 begins at Six Flags Great America.
- 2018 – Fright Fest 2018 begins at Six Flags Magic Mountain.
A list of events that occurred on September 15 related to Six Flags.