Carrier route record
UADEN→RDU
United Airlines · Denver to Raleigh
- Flights
- 775
- Period
- July 2025 to June 2026
- Share of route
- 44%
- Carriers
- 3
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with United Airlines.
United on DEN to RDU lands a B+, 3 points better than the national rate of 77.6%. About one flight in five arrives 15 minutes late or worse, and those flights are late by about an hour on average. That is a workable record, not a spotless one. That rests on 775 flights, with a median arrival 6 minutes early.
The US average over the same twelve months is 77.6%, so there is little to separate United on DEN to RDU from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
80.9%
Arrivals under 15 minutes late, of 769 completed flights
Avg delay
60 min
Across delayed arrivals only, not all flights
Cancelled
0.52%
National rate is 1.81%
Whole route
75.2%
Every carrier on DEN to RDU, 1,768 flights
These figures cover 775 flights between July 2025 and June 2026. The median arrival is 6 minutes early, which is the part an average hides: most flights here are fine, and the on-time rate is decided by a tail of badly late ones. On-time means under 15 minutes late, the DOT's own threshold.
Carrier by carrier
United against every carrier on DEN to RDU
United flew 775 of the 1,768 flights on DEN to RDU, about 44% of it. Its 80.9% on time is 6 points better than the route as a whole, which runs 75.2%. Ranked by on-time rate it is number two of three carriers on the route, where the range runs from Frontier at 86.1% to Southwest at 64.6%. One of those carriers flew fewer than 365 flights here, so treat their positions as rough.
Only one carrier clears this site's 365-flight floor here, so there is no comparison to draw. The table below is the full picture.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Frontier Airlinesthin sample | 285 | 86.1% | 54 min | 1.40% | A |
| United Airlines (this page) | 775 | 80.9% | 60 min | 0.52% | B+ |
| Southwest Airlines | 708 | 64.6% | 53 min | 0.71% | D+ |
Flight by flight
United flight numbers on DEN to RDU
Departure window
When United runs best on this route
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 12 points, against half a point between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am—
- 8am–11am364 flights86.7%
- 11am–2pm—
- 2pm–5pm5 flights—
- 5pm–8pm359 flights74.4%
- 8pm–5am47 flights83.0%
Scale runs 65% to 90%. Rows with fewer than 30 flights show a dash.
Book the morning departure. Flights leaving between 8am–11am arrive on time 86.7% of the time, against 74.4% for the evening window. That is 12 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 8am–11am window is the busiest, with 364 flights scheduled in it.
Across the year
United on DEN to RDU through the year
July is the worst month at 67.4% on time, 24 points below April, the best at 91.7%. Summer afternoon convection and peak-season schedules land on the same weeks every year, so this is a pattern you can book around rather than a run of bad luck. July was the busiest month here, with 92 flights.
Across the week, Tuesday is the strongest day at 88.5% on time and Thursday the weakest at 76.4%. 12 points is a smaller lever than departure hour, but it is free.
Delay causes
Why United runs late on this route
One category carries most of the weight here. Late-arriving aircraft accounts for 43% of the 8,818 delay minutes carriers reported, and the remaining four split what is left. The split is by minutes rather than by flights, so a few very long delays count for as much as many short ones.
- 43%Late-arriving aircraft
- 28%National Airspace System
- 27%Carrier
- 2%Extreme weather
43% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. That is a cascade, and cascades start small and grow through the day. Across 8,818 reported delay minutes here, that single category outweighs weather by 19 to one. It is the strongest argument for booking the first departure of the morning, when the aircraft has been sitting at the gate overnight with nothing to inherit. The split is drawn from 8,818 reported delay minutes.
The practical consequence: the 8am–11am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 86.7% on time here.
Cancellations are rare at 0.52%, below the national 1.81% and low enough to earn the plus on the grade. Roughly one flight in 100 is called off; the risk here is arriving late, not not arriving.
Connections and stage length
What a delay here costs
6.6% of arrivals land an hour or more late, close to the national 8.1%. That is the figure that decides a connection, and it says a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last about an hour, which a normal layover absorbs.
The 1,436 miles between these two airports put this in the middle of the US network, around two and a half to three hours of block time. That is enough cruise to absorb a ten-minute late pushback and not enough to absorb thirty. It is also long enough that the aircraft usually flies three or four legs a day rather than six, which slows how fast delay compounds.
The return leg is a different operation and performs like one: it runs 86.3% on time across 776 flights, 5 points above this direction. Departure banks, aircraft rotations and the congestion at each end all differ, so scoring the two directions together would average away a real 5 points of difference.
One caution: this is a thin sample. 775 flights over twelve months is enough to clear this site's floor but not enough to pin the rate down tightly, and a single bad week moves it by more than a point. Treat the grade as a rough reading.
What to do with this
Booking United on DEN to RDU
Put together: treat all of this as provisional. 775 flights over twelve months is enough to clear this site's floor and not enough to be confident to better than a couple of points. The 80.9% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 769 completed flights over 12 months sit behind that.
Related
Where to go next
- DEN to RDU, every carrier
- United on RDU to DEN, the return leg
- Frontier Airlines on DEN to RDU86.1%
- Southwest Airlines on DEN to RDU64.6%
- United Airlines network-wide record
- Denver International (DEN) delay statistics
- Raleigh-Durham International (RDU) delay statistics
- Why the first flight of the morning is statistically safest
- The best time of day to fly, according to 7.04 million flight records
Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Last updated 15 September 2026; recomputed monthly. How this data is collected.