About 1 in 4 UA 4666 flights from Casper arrived 15+ minutes late, diverted or cancelled over the past year (25%); 1.9% were cancelled. The typical flight landed 5 minutes early.
UA 4666: CPR → DEN
Scheduled to leave Casper at 5:55 p.m. local time, operated by SkyWest as OO 4666. Over the past year it arrived on time 75% of the time (269 flights), better than other UA flights on the route at that hour (71%). Last seen in the data Aug 31, 2026.
Usually United Airlines's last flight of the day from Casper to Denver (100% of days). United Airlines's last CPR–DEN flight was cancelled 1.4% of the time, against 0.9% for its earlier ones. If it's cancelled, the next United Airlines flight is usually around 5:15 a.m. the next morning.
Month by month
By day of week
| Day | Flights | On time |
|---|---|---|
| Monday | 38 | 76% |
| Tuesday | 39 | 87% |
| Wednesday | 38 | 82% |
| Thursday | 39 | 79% |
| Friday | 39 | 62% |
| Saturday | 38 | 71% |
| Sunday | 38 | 68% |
Why it was late
All flights CPR → DEN · Connecting off UA 4666? Check the risk
Questions
How often is UA 4666 from CPR to DEN late?
United Airlines 4666 from Casper, WY to Denver, CO arrived 15 or more minutes late, was diverted or was cancelled on 25% of 269 scheduled flights between September 2025 and August 2026. 1.9% 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.