Flight history · Aug 2025 – Jul 2026 · US DOT on-time records
WN 3912 · St Louis (STL) → Denver (DEN)
Sold by Southwest. Still flying: 56 of the last 56 days (Daily).
Arrives on time51%within 15 minutes, of 58 flights
Cancelled0.0%of scheduled flights
An hour or more late19%of flights that operated
When late, on average71 minlate, among flights 15+ min late
Schedule
Typical times in the Jun 6 – Jul 31, 2026 schedule, local at each airport (Denver is 1 h behind St Louis).
- Leaves STL
- 16:00
- Arrives DEN
- 17:20
- Flight time
- 2h 20m
- Days flown, last 8 weeks
- 56 of 56
Each square is a day, Sat Jun 6 to Fri Jul 31, two weeks per row (each column is the same weekday); filled = flew.
How late it arrives
Share of flights that operated arriving more than this late.
Horizontal: minutes late at arrival (0 to 3 hours). Vertical: share of flights later than that.
Its hour at STL
All flights leaving St Louis (STL) at 4–5 pm, wherever they’re going: 64% left within 15 minutes and 1.7% were cancelled (3,208 flights in the year). Other Southwest flights on this route →
Upcoming forecasts
Our odds that this flight is late or cancelled on the days we publish.