Flight OddsSouthwest Airlines · St. Louis, MO to San Francisco, CA · 28 flights observed, 2026-03-05 to 2026-04-06 · 1,735 mi
WN4555 covers more than one route in the data window — the stats below are for STL → SFO, the one it has flown most recently. The others are linked under “Other routes”.
How often is WN4555 on time?
Across 28 flights on STL → SFO from 2026-03-05 to 2026-04-06, WN4555 arrived within 15 minutes of schedule 93% of the time. The median arrival delay was 0 min, and the worst 10% of flights arrived +8 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 | 26 | 93% |
| 16-30 min | 1 | 4% |
| 31-60 min | 0 | 0% |
| 61-120 min | 1 | 4% |
| 2+ hrs | 0 | 0% |
Performance by month
| Month | Flights | On-time | Avg delay |
|---|---|---|---|
| 2026-03 | 23 | 96% | -2 min |
| 2026-04 | 5 | 80% | +11 min |
Performance by day of week
| Day | Flights | On-time |
|---|---|---|
| Mon | 5 | 100% |
| Tue | 4 | 100% |
| Wed | 4 | 50% |
| Thu | 5 | 100% |
| Fri | 5 | 100% |
| Sat | No data | — |
| Sun | 5 | 100% |
Other routes
Related
Based on US Department of Transportation Bureau of Transportation Statistics on-time data. Loading live conditions and full charts…