Flight OddsUA4527 IAD → STL
United Airlines · Washington, DC to St. Louis, MO · 365 flights observed, 2025-07-01 to 2026-06-30 · 696 mi
On-time arrival
71%
Median delay
-9 min
90th percentile
+119 min
Cancellation rate
1%
How often is UA4527 on time?
Across 365 flights on IAD → STL from 2025-07-01 to 2026-06-30, UA4527 arrived within 15 minutes of schedule 71% of the time. The median arrival delay was -9 min, and the worst 10% of flights arrived +119 min or later. 1% of flights were cancelled.
Delay distribution
Arrival delay for completed flights (excludes cancellations and diversions).
| Arrival | Flights | Share |
|---|---|---|
| Early / on-time | 258 | 71% |
| 16-30 min | 17 | 5% |
| 31-60 min | 23 | 6% |
| 61-120 min | 28 | 8% |
| 2+ hrs | 35 | 10% |
Performance by month
| Month | Flights | On-time | Avg delay |
|---|---|---|---|
| 2025-07 | 31 | 58% | +70 min |
| 2025-08 | 31 | 68% | +25 min |
| 2025-09 | 30 | 80% | +3 min |
| 2025-10 | 31 | 81% | +10 min |
| 2025-11 | 30 | 70% | +37 min |
| 2025-12 | 31 | 61% | +50 min |
| 2026-01 | 29 | 59% | +32 min |
| 2026-02 | 27 | 85% | +12 min |
| 2026-03 | 31 | 71% | +44 min |
| 2026-04 | 29 | 83% | -9 min |
| 2026-05 | 31 | 74% | +21 min |
| 2026-06 | 30 | 70% | +43 min |
Performance by day of week
| Day | Flights | On-time |
|---|---|---|
| Mon | 51 | 63% |
| Tue | 53 | 75% |
| Wed | 52 | 75% |
| Thu | 52 | 77% |
| Fri | 52 | 62% |
| Sat | 50 | 80% |
| Sun | 51 | 69% |
Related
Based on US Department of Transportation Bureau of Transportation Statistics on-time data. Loading live conditions and full charts…