Flight OddsUA4423 STL → ORD
United Airlines · St. Louis, MO to Chicago, IL · 331 flights observed, 2025-07-01 to 2026-06-29 · 258 mi
UA4423 covers more than one route in the data window — the stats below are for STL → ORD, the one it has flown most recently. The others are linked under “Other routes”.
On-time arrival
85%
Median delay
-8 min
90th percentile
+35 min
Cancellation rate
1%
How often is UA4423 on time?
Across 331 flights on STL → ORD from 2025-07-01 to 2026-06-29, UA4423 arrived within 15 minutes of schedule 85% of the time. The median arrival delay was -8 min, and the worst 10% of flights arrived +35 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 | 276 | 85% |
| 16-30 min | 13 | 4% |
| 31-60 min | 14 | 4% |
| 61-120 min | 13 | 4% |
| 2+ hrs | 9 | 3% |
Performance by month
| Month | Flights | On-time | Avg delay |
|---|---|---|---|
| 2025-07 | 30 | 77% | +8 min |
| 2025-08 | 31 | 84% | -4 min |
| 2025-09 | 30 | 97% | 0 min |
| 2025-10 | 31 | 100% | -9 min |
| 2025-11 | 29 | 86% | +9 min |
| 2025-12 | 30 | 80% | +17 min |
| 2026-01 | 28 | 75% | +8 min |
| 2026-02 | 27 | 81% | -1 min |
| 2026-03 | 29 | 76% | +9 min |
| 2026-04 | 1 | 100% | 0 min |
| 2026-05 | 30 | 93% | +3 min |
| 2026-06 | 29 | 83% | 0 min |
Performance by day of week
| Day | Flights | On-time |
|---|---|---|
| Mon | 48 | 79% |
| Tue | 46 | 89% |
| Wed | 45 | 91% |
| Thu | 45 | 93% |
| Fri | 47 | 83% |
| Sat | 47 | 87% |
| Sun | 47 | 72% |
Other routes
Related
Based on US Department of Transportation Bureau of Transportation Statistics on-time data. Loading live conditions and full charts…