Flight profile · United Airlines
UA641
Washington (IAD) to Boston (BOS) · scheduled 8:50 AM – 9:55 AM
How UA641 performs
1,072 operations, 2023-07-01 to 2026-06-30.
UA641 arrived on time 91.8% of the time, against 77.6% for all IAD → BOS flights — this specific departure is 14.2 percentage points better than the route as a whole. Against United Airlines’s own flights on this route it is 14.2 points better.
Source: US DOT Bureau of Transportation Statistics · 1,072 operations between 2023-07-01 to 2026-06-30
Against the rest of the route
| On time | Cancelled | Median delay | Severe | Flights | |
|---|---|---|---|---|---|
| UA641 | 91.8% | 2.05% | -10 min | 3.1% | 1,072 |
| United Airlines on IAD → BOS | 77.6% | 1.48% | -5 min | 8.9% | 4,463 |
| All IAD → BOS flights | 77.6% | 1.47% | -5 min | 8.9% | 4,475 |
Source: FlyerIntel analysis of US DOT BTS data · 2023-07-01 to 2026-06-30
By day of week
Does UA641 run worse on particular days?
Thursday is historically the most reliable day and Sunday the least, a gap of 5.5 percentage points.
Source: FlyerIntel analysis of US DOT BTS data · 2023-07-01 to 2026-06-30 · Days with fewer than 120 operations are not scored.
Other routes UA641 has flown
A flight number is a slot in a schedule, and carriers reassign it. These are the other city pairs this number served in the analysis period.
Because the same number has served different journeys, the statistics above describe only the route UA641 currently operates. Blending them would produce an average of two different flights.
Data and methodology
Calculated by FlyerIntel from 1,072 records of UA641 operating IAD → BOS, published by the US DOT Bureau of Transportation Statistics. A flight counts as delayed when it arrives 15 or more minutes after schedule. Cancelled and diverted flights are excluded from the on-time rate and reported separately. Flight numbers are resolved as carrier plus number plus route, because the same number serves different routes over time.