Flight OddsUA4231 IAH → BHM
United Airlines · Houston, TX to Birmingham, AL · 154 flights observed, 2026-01-06 to 2026-06-30 · 562 mi
UA4231 covers more than one route in the data window — the stats below are for IAH → BHM, the one it has flown most recently. The others are linked under “Other routes”.
On-time arrival
88%
Median delay
-13 min
90th percentile
+22 min
Cancellation rate
1%
How often is UA4231 on time?
Across 154 flights on IAH → BHM from 2026-01-06 to 2026-06-30, UA4231 arrived within 15 minutes of schedule 88% of the time. The median arrival delay was -13 min, and the worst 10% of flights arrived +22 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 | 133 | 88% |
| 16-30 min | 5 | 3% |
| 31-60 min | 5 | 3% |
| 61-120 min | 7 | 5% |
| 2+ hrs | 2 | 1% |
Performance by month
| Month | Flights | On-time | Avg delay |
|---|---|---|---|
| 2026-01 | 25 | 92% | -5 min |
| 2026-02 | 27 | 81% | -5 min |
| 2026-03 | 31 | 87% | -3 min |
| 2026-04 | 29 | 90% | -11 min |
| 2026-05 | 10 | 80% | +3 min |
| 2026-06 | 30 | 90% | +1 min |
Performance by day of week
| Day | Flights | On-time |
|---|---|---|
| Mon | 22 | 77% |
| Tue | 23 | 87% |
| Wed | 21 | 86% |
| Thu | 22 | 95% |
| Fri | 22 | 91% |
| Sat | 21 | 100% |
| Sun | 21 | 76% |
Other routes
Related
Based on US Department of Transportation Bureau of Transportation Statistics on-time data. Loading live conditions and full charts…