Flight OddsUA721 BOS → IAD
United Airlines · Boston, MA to Washington, DC · 316 flights observed, 2025-08-19 to 2026-06-30 · 412 mi
UA721 covers more than one route in the data window — the stats below are for BOS → IAD, the one it has flown most recently. The others are linked under “Other routes”.
On-time arrival
79%
Median delay
-2 min
90th percentile
+47 min
Cancellation rate
3%
How often is UA721 on time?
Across 316 flights on BOS → IAD from 2025-08-19 to 2026-06-30, UA721 arrived within 15 minutes of schedule 79% of the time. The median arrival delay was -2 min, and the worst 10% of flights arrived +47 min or later. 3% of flights were cancelled.
Delay distribution
Arrival delay for completed flights (excludes cancellations and diversions).
| Arrival | Flights | Share |
|---|---|---|
| Early / on-time | 241 | 79% |
| 16-30 min | 21 | 7% |
| 31-60 min | 18 | 6% |
| 61-120 min | 15 | 5% |
| 2+ hrs | 12 | 4% |
Performance by month
| Month | Flights | On-time | Avg delay |
|---|---|---|---|
| 2025-08 | 13 | 77% | +11 min |
| 2025-09 | 28 | 75% | +25 min |
| 2025-10 | 30 | 57% | +22 min |
| 2025-11 | 29 | 69% | +24 min |
| 2025-12 | 31 | 77% | +13 min |
| 2026-01 | 29 | 76% | +11 min |
| 2026-02 | 26 | 92% | +2 min |
| 2026-03 | 31 | 81% | +9 min |
| 2026-04 | 30 | 93% | +1 min |
| 2026-05 | 30 | 87% | +1 min |
| 2026-06 | 30 | 80% | +9 min |
Performance by day of week
| Day | Flights | On-time |
|---|---|---|
| Mon | 43 | 81% |
| Tue | 45 | 87% |
| Wed | 43 | 72% |
| Thu | 44 | 82% |
| Fri | 45 | 71% |
| Sat | 44 | 84% |
| Sun | 43 | 72% |
Other routes
Related
Based on US Department of Transportation Bureau of Transportation Statistics on-time data. Loading live conditions and full charts…