Flight OddsWN2521 DEN → STL
Southwest Airlines · Denver, CO to St. Louis, MO · 15 flights observed, 2025-08-09 to 2025-09-28 · 770 mi
WN2521 covers more than one route in the data window — the stats below are for DEN → STL, the one it has flown most recently. The others are linked under “Other routes”.
On-time arrival
50%
Median delay
+11 min
90th percentile
+118 min
Cancellation rate
7%
How often is WN2521 on time?
Across 15 flights on DEN → STL from 2025-08-09 to 2025-09-28, WN2521 arrived within 15 minutes of schedule 50% of the time. The median arrival delay was +11 min, and the worst 10% of flights arrived +118 min or later. 7% of flights were cancelled.
Delay distribution
Arrival delay for completed flights (excludes cancellations and diversions).
| Arrival | Flights | Share |
|---|---|---|
| Early / on-time | 7 | 50% |
| 16-30 min | 3 | 21% |
| 31-60 min | 2 | 14% |
| 61-120 min | 0 | 0% |
| 2+ hrs | 2 | 14% |
Performance by month
| Month | Flights | On-time | Avg delay |
|---|---|---|---|
| 2025-08 | 6 | 33% | +71 min |
| 2025-09 | 8 | 63% | +5 min |
Performance by day of week
| Day | Flights | On-time |
|---|---|---|
| Mon | No data | — |
| Tue | No data | — |
| Wed | No data | — |
| Thu | No data | — |
| Fri | No data | — |
| Sat | 8 | 50% |
| Sun | 6 | 50% |
Other routes
Related
Based on US Department of Transportation Bureau of Transportation Statistics on-time data. Loading live conditions and full charts…