Carrier route record
UARDU→DEN
United Airlines · Raleigh to Denver
- Flights
- 727
- Period
- September 2025 to August 2026
- Share of route
- 42%
- Carriers
- 3
Historical statistics for September 2025 to August 2026, not live status. For today’s flights, check with United Airlines.
United on RDU to DEN earns an A+. Close to nine flights in ten arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 10 points better than the national rate of 77.3%. When something does go wrong the average delay runs an hour and a half. That rests on 727 flights, with a median arrival 9 minutes early.
Set against the rest of the country, United's RDU to DEN record is 10 points better than the US average of 77.3%. That gap is worth roughly 104 fewer late arrivals for every thousand flights.
Key figures
On time
87.7%
Arrivals under 15 minutes late, of 723 completed flights
Avg delay
89 min
Across delayed arrivals only, not all flights
Cancelled
0.41%
National rate is 1.89%
Whole route
81.9%
Every carrier on RDU to DEN, 1,734 flights
These figures cover 727 flights between September 2025 and August 2026. The median arrival is 9 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.
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Carrier by carrier
United against every carrier on RDU to DEN
United flew 727 of the 1,734 flights on RDU to DEN, about 42% of it. Its 87.7% on time is 6 points better than the route as a whole, which runs 81.9%. Ranked by on-time rate it is first of three carriers on the route, where the range runs from United at 87.7% to Southwest at 74.8%. 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 |
|---|---|---|---|---|---|
| United Airlines (this page) | 727 | 87.7% | 89 min | 0.41% | A+ |
| Frontier Airlinesthin sample | 297 | 84.6% | 79 min | 1.01% | B |
| Southwest Airlines | 710 | 74.8% | 55 min | 0.99% | C+ |
Flight by flight
United flight numbers on RDU to DEN
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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 10 points, against half a point between the best and worst carrier.
- 5am–8am—
- 8am–11am364 flights92.8%
- 11am–2pm—
- 2pm–5pm363 flights82.5%
- 5pm–8pm—
- 8pm–5am—
Scale runs 75% to 100%. Rows with fewer than 30 flights show a dash.
Book the morning departure. Flights leaving between 8am–11am arrive on time 92.8% of the time, against 82.5% for the afternoon window. That is 10 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 RDU to DEN through the year
July is the worst month at 75.4% on time, 21 points below May, the best at 96.8%. 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. January was the busiest month here, with 62 flights.
Across the week, Tuesday is the strongest day at 91.3% on time and Thursday the weakest at 83.5%, a spread of 8 points.
Arrival by arrival
How late United on RDU to DEN runs when it is late
United on RDU to DEN often beats the schedule: 242 of 723 completed flights, 33%, arrived 15 minutes or more early. The 89 late arrivals split 30 under half an hour, 22 between 30 and 60 minutes, and 37 an hour or more.
- 15+ min early242 flights33.5%
- Within 15 min392 flights54.2%
- 15–29 min late30 flights4.1%
- 30–59 min late22 flights3.0%
- 1–2 hours late15 flights2.1%
- 2+ hours late22 flights3.0%
Scale runs 0% to 100%.
Share of 723 completed flights by arrival against schedule.
26 of 88 late departures made up the time and arrived on time, 30% of them. 27 flights left on time and still arrived late.
The worst days
Worst days for United on RDU to DEN
The latest arrival of the period was on 17 April 2026, 8 hours 43 minutes behind schedule; most of its delay minutes were filed as a late-arriving aircraft. On three of the five worst days the largest share was filed as carrier-caused (crew, maintenance, fuelling, baggage).
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 17 April 2026 | 8 hours 43 minutes | Late-arriving aircraft |
| 6 June 2026 | 7 hours 26 minutes | Carrier |
| 12 July 2026 | 6 hours 52 minutes | Carrier |
| 6 November 2025 | 5 hours 35 minutes | Carrier |
| 19 December 2025 | 5 hours 8 minutes | Late-arriving aircraft |
Delay causes
Why United runs late on this route
Carriers report a reason for every delay minute they cause, in five DOT categories. The split below is by minutes, not by number of flights, so a handful of very long weather delays weighs as much as many short ones. It covers 7,936 reported delay minutes.
- 38%Late-arriving aircraft
- 34%Carrier
- 28%National Airspace System
- 0%Extreme weather
38% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 7,936 reported delay minutes here, that single category outweighs weather by 38 to one. The split is drawn from 7,936 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 92.8% on time here.
Cancellations are rare at 0.41%, below the national 1.89% 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
5.1% of arrivals land an hour or more late, close to the national 8.3%, so a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last an hour and a half, 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.
The return leg is a different operation and performs like one: it runs 82.3% on time across 727 flights, 5 points below 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. 727 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 RDU to DEN
Put together: treat all of this as provisional. 727 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 87.7% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 723 completed flights over 12 months sit behind that.
Related
Where to go next
- RDU to DEN, every carrier
- United on DEN to RDU, the return leg
- Frontier Airlines on RDU to DEN84.6%
- Southwest Airlines on RDU to DEN74.8%
- United Airlines network-wide record
- Raleigh-Durham International (RDU) delay statistics
- Denver International (DEN) delay statistics
- Why the first flight of the morning is statistically safest
- The best time of day to fly, according to 7.05 million flight records
Source: US DOT Bureau of Transportation Statistics, on-time performance data, September 2025 to August 2026. Last updated ; recomputed monthly. How this data is collected.