About 1 in 9 UA 4251 flights from Greensboro arrived 15+ minutes late, diverted or cancelled over the past year (11%); 0.7% were cancelled. The typical flight landed 12 minutes early.
UA 4251: GSO → IAD
Scheduled to leave Greensboro at 6:15 a.m. local time, operated by CommutAir as C5 4251. Over the past year it arrived on time 89% of the time (149 flights), in line with other UA flights on the route at that hour (89%). Last seen in the data Aug 31, 2026.
Month by month
By day of week
| Day | Flights | On time |
|---|---|---|
| Monday | 23 | 91% |
| Tuesday | 18 | — |
| Wednesday | 18 | — |
| Thursday | 23 | 87% |
| Friday | 23 | 96% |
| Saturday | 22 | 91% |
| Sunday | 22 | 82% |
Why it was late
All flights GSO → IAD · Connecting off UA 4251? Check the risk
Questions
How often is UA 4251 from GSO to IAD late?
United Airlines 4251 from Greensboro/High Point, NC to Washington, DC arrived 15 or more minutes late, was diverted or was cancelled on 11% of 149 scheduled flights between September 2025 and August 2026. 0.7% were cancelled.
Flight numbers change. Figures cover flights with this airline, number and route only. "Likely range" is the 95% interval for the true on-time rate given the number of flights. This is history, not live status: check United Airlines for today's flight. Method.