Flight OddsWN4420 STL → BOS
Southwest Airlines · St. Louis, MO to Boston, MA · 31 flights observed, 2025-10-02 to 2025-11-01 · 1,047 mi
WN4420 covers more than one route in the data window — the stats below are for STL → BOS, the one it has flown most recently. The others are linked under “Other routes”.
On-time arrival
71%
Median delay
0 min
90th percentile
+29 min
Cancellation rate
0%
How often is WN4420 on time?
Across 31 flights on STL → BOS from 2025-10-02 to 2025-11-01, WN4420 arrived within 15 minutes of schedule 71% of the time. The median arrival delay was 0 min, and the worst 10% of flights arrived +29 min or later. 0% of flights were cancelled.
Delay distribution
Arrival delay for completed flights (excludes cancellations and diversions).
| Arrival | Flights | Share |
|---|---|---|
| Early / on-time | 22 | 71% |
| 16-30 min | 6 | 19% |
| 31-60 min | 1 | 3% |
| 61-120 min | 2 | 6% |
| 2+ hrs | 0 | 0% |
Performance by month
| Month | Flights | On-time | Avg delay |
|---|---|---|---|
| 2025-10 | 30 | 70% | +9 min |
| 2025-11 | 1 | 100% | -25 min |
Performance by day of week
| Day | Flights | On-time |
|---|---|---|
| Mon | 4 | 50% |
| Tue | 4 | 25% |
| Wed | 4 | 75% |
| Thu | 5 | 100% |
| Fri | 5 | 80% |
| Sat | 5 | 80% |
| Sun | 4 | 75% |
Other routes
Related
Based on US Department of Transportation Bureau of Transportation Statistics on-time data. Loading live conditions and full charts…