Fright Fest 2026 at Six Flags St Louis: crowd calendar
Fright Fest 2026 at Six Flags St Louis runs 12 Sep to 1 Nov 2026 and is forecast moderately busy, averaging 53% crowd level. The quietest night is Sat 12 Sep at 5%, the busiest Sat 17 Oct at 85%.
Quietest night of Fright Fest 2026
Fright Fest 2026 is forecast moderately busy at Six Flags St Louis, averaging 53% crowd level across its 21 nights. The busiest is Saturday 17 Oct at 85%.
Across its 22 nights the forecast averages 53% crowd level, which is about a normal day for this park. That is about the same as the same weeks in 2025, which measured 50%.
Fright Fest is an evening event, so the crowd figures above describe the whole day at Six Flags St Louis, not the event hours alone. Boo Fest runs alongside it during the day, on the same dates.
Every night, with the forecast
October 2026
November 2026
The 29 days inside the run that Fright Fest does not operate on are forecast 36% on average, quieter than the event nights.
How the same weeks ran in 2025
Between 12 Sep and 1 Nov 2025 the park measured 50% on average over 8 recorded days. The busiest was Saturday 11 Oct at 67%, the quietest Sunday 5 Oct at 39%. These are the same calendar weeks, not necessarily 2025's event dates.
Busiest days, measured
- 1Saturday 11 Oct67%
- 2Sunday 12 Oct58%
- 3Saturday 27 Sept50%
- 4Saturday 1 Nov48%
- 5Saturday 25 Oct46%
Quietest days, measured
- 1Sunday 5 Oct39%
- 2Saturday 4 Oct43%
- 3Saturday 13 Sept45%
- 4Saturday 25 Oct46%
- 5Saturday 1 Nov48%
Dates as published by Six Flags St Louis; always check the park's own site before travelling. Crowd levels are modelled from this park's own recorded queue times, school and public holidays, day of the week and the weather forecast, and may not always be right. We score every past forecast against what the queues actually did and publish the result in the crowd forecast accuracy ledger.
Frequently asked
When is Fright Fest 2026 at Six Flags St Louis?
Fright Fest 2026 runs 12 Sep to 1 Nov 2026, on Fridays to Sundays: 22 nights in total. Dates are as published by Six Flags St Louis.
What is the quietest night of Fright Fest 2026?
Saturday 12 Sept is forecast the quietest at 5% crowd level. The next best are Sun 13 Sep (5%), Fri 2 Oct (36%), Fri 30 Oct (39%).
What is the busiest night of Fright Fest 2026?
Saturday 17 Oct is forecast the busiest at 85%. The 8 nights that fall in the Summer (12 Sep to 30 Oct) average 45%.
How busy is Fright Fest compared with a normal day at Six Flags St Louis?
The event nights average 53% crowd level, about a normal day for this park. The same weeks in 2025 measured 50% on average. The 29 days inside the run that Fright Fest does not operate on are forecast 36% on average, quieter than the event nights.
Do I need a separate ticket for Fright Fest?
Fright Fest runs in the evening, with Boo Fest during the day. Check Six Flags St Louis's own site for what your ticket includes on the day you visit.