Flight OddsUA1521 IAH → SFO
United Airlines · Houston, TX to San Francisco, CA · 25 flights observed, 2025-11-01 to 2025-12-01 · 1,635 mi
UA1521 covers more than one route in the data window — the stats below are for IAH → SFO, the one it has flown most recently. The others are linked under “Other routes”.
On-time arrival
60%
Median delay
+5 min
90th percentile
+85 min
Cancellation rate
0%
How often is UA1521 on time?
Across 25 flights on IAH → SFO from 2025-11-01 to 2025-12-01, UA1521 arrived within 15 minutes of schedule 60% of the time. The median arrival delay was +5 min, and the worst 10% of flights arrived +85 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 | 15 | 60% |
| 16-30 min | 2 | 8% |
| 31-60 min | 5 | 20% |
| 61-120 min | 3 | 12% |
| 2+ hrs | 0 | 0% |
Performance by month
| Month | Flights | On-time | Avg delay |
|---|---|---|---|
| 2025-11 | 24 | 58% | +22 min |
| 2025-12 | 1 | 100% | -1 min |
Performance by day of week
| Day | Flights | On-time |
|---|---|---|
| Mon | 5 | 40% |
| Tue | 1 | 0% |
| Wed | 1 | 100% |
| Thu | 4 | 50% |
| Fri | 4 | 50% |
| Sat | 5 | 80% |
| Sun | 5 | 80% |
Other routes
Related
Based on US Department of Transportation Bureau of Transportation Statistics on-time data. Loading live conditions and full charts…