Route profile
DEN→RDU
Flight reliability, delays and best times to fly from Denver to Raleigh–Durham, 1,436 miles.
Right now
Aviation weather is not currently a factor.
Aviation weather is not currently a factor.
Route reliability
July 2023 – July 2026
Better than 42% of comparable major US routes (4,598 compared)
Calculated from 5,870 flights. How this is calculated · What counts as on time
DEN → RDU arrives on time 73.4% of the time; the return trip, RDU → DEN, arrives on time 80.8% of the time, a 7.5-point gap between the two directions of the same city pair.
DEN → RDU spends 25.3 minutes on the ground on a 1,436-mile trip: 19.6 minutes from pushback to wheels-up at DEN and 5.7 minutes from touchdown to gate at RDU.
Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – July 2026
What stands out
On-time performance swings unusually widely by time of day here, wider than 97% of 4,023 comparable routes.
85.8% on time for 5–9 AM departures, against 51.2% for 6–9 PM.
Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026 · Ranked against every other route with the same kind of figure and at least 4,023 in the comparison.
What sets this route apart
Where DEN to RDU differs most from similar routes by hour, weekday, month and airline, July 2023 – July 2026.
DEN to RDU struggles most at 6 PM: 48.5% of its flights scheduled then arrive on time, 21.9 points behind the 70.4% on routes of similar length at the same hour. Against all other routes the gap is 20.1 points.
Tuesday is the day DEN to RDU slips furthest against routes of similar length, 74.5% on time where they average 80.8%, 6.3 points lower. Against all other routes the gap is 7.1 points.
In August, DEN to RDU runs 9.9 points below routes of similar length, 66.7% on time to 76.6%. Against all other routes the gap is 9.8 points.
Southwest Airlines’ flights on DEN to RDU arrive on time 63.3% of the time, 12.7 points below the 76.0% it manages on its routes of similar length. Against all other routes the gap is 14.1 points.
Frontier Airlines does better on DEN to RDU than on its routes of similar length: 77.5% on time here, 69.7% there, 7.8 points apart. Against all other routes the gap is 6.3 points.
DEN to RDU against comparable routes
July 2023 – July 2026| Measure | This route | Compared with | Them | Gap | Flights behind it |
|---|---|---|---|---|---|
| Hour: 6 PM departures | 48.5% | routes of similar length | 70.4% | −21.9 pts | 355 here, 108,822 there |
| Weekday: Tuesday | 74.5% | routes of similar length | 80.8% | −6.3 pts | 808 here, 214,670 there |
| Month: August | 66.7% | routes of similar length | 76.6% | −9.9 pts | 534 here, 129,978 there |
| Airline: Southwest Airlines | 63.3% | routes of similar length | 76.0% | −12.7 pts | 2,136 here, 349,127 there |
| Airline: Frontier Airlines | 77.5% | routes of similar length | 69.7% | +7.8 pts | 1,113 here, 64,405 there |
Each comparison pools the flights of other routes, with this route’s own left out. Similar length means within 15% of this route’s 1,436 miles, with at least 5 such routes. A bucket is set against the most comparable group that has enough flights: similar length, then the same origin (at least 3 routes), then all other routes. Hours, weekdays and months appear only where both sides have 120 completed flights, and airlines where both have 600. The gap must be at least 2 points and 2 standard errors, and only the largest gap each way is kept per measure. These are differences in the flights counted, not causes.
When it goes wrong
July 2023 – July 2026
49 min late
against a median of 2 min early
Percentiles over 5,870 operations; cancelled and diverted flights are counted separately.
Will your connection be tight enough?
Layovers at RDU after arriving from DEN.
| Connection time | Chance of missing | Reads as |
|---|---|---|
| 30 min | 46% | Likely to miss |
| 45 min | 26% | High risk |
| 60 min | 16% | High risk |
| 90 min | 7.7% | Some risk |
| 120 min | 4.0% | Low risk |
This is one leg of a connection. Gate changes and the next flight's own schedule matter too. And a connection can fail before delay is even the question — this route cancels 0.66% of the time and diverts 0.17% of the time, which a late arrival never shows up in.
Chance of missing is the share of 5,821 arrivals on this route that landed later than the connection time less 30 minutes to reach the next gate.
The worst tenth of arrivals on this route land at least 49 minutes late (90th-percentile gate arrival delay), over 5,870 operations.
Any other layover length: connection checker.
Best time to fly
DEN → RDU flights departing 5–9 AM arrived on time 85.8% of the time, against 51.2% for 6–9 PM departures, a gap of 34.6 percentage points.
By departure window
By departure hour
- 12 AM to 5 AM: too few flights to score
- 6 AM: 88.8% on time from 162 flights
- 7 AM to 8 AM: too few flights to score
- 9 AM: 83.2% on time from 1,292 flights
- 10 AM: 77.5% on time from 505 flights
- 11 AM: 75.8% on time from 567 flights
- 12 PM: too few flights to score
- 1 PM: 79.7% on time from 233 flights
- 2 PM: too few flights to score
- 3 PM: 70.3% on time from 303 flights
- 4 PM: 75.8% on time from 126 flights
- 5 PM: 70.2% on time from 1,282 flights
- 6 PM: 48.5% on time from 356 flights
- 7 PM: 51.9% on time from 481 flights
- 8 PM to 10 PM: too few flights to score
- 11 PM: 85.6% on time from 190 flights
Why DEN → RDU runs late
July 2023 – July 2026
the inbound aircraft was late, so this flight started late
crew, maintenance, boarding and fueling, all within the carrier’s control
airspace and airport capacity, including weather-driven flow control
weather severe enough to stop this flight specifically
screening or terminal security incidents
Share of the delay minutes US DOT attributed to each cause for DEN → RDU. Only delays of 15 minutes or more are attributed. What the five causes mean
Late-arriving aircraft is the largest cause on DEN → RDU, at 46.0%: flights here mostly leave late because the plane came in late, and the day shows it: 5–9 AM departures arrived on time 85.8% of the time and 6–9 PM departures 51.2%.
Airlines on this route
Carriers with at least 200 flights, by the airline that operated each one.
| Carrier | Flights | On time | Cancelled | Median delay | Severe |
|---|---|---|---|---|---|
| United Airlines | 2,596 | 79.9% | 0.73% | -6 min | 6.3% |
| Southwest Airlines | 2,148 | 63.3% | 0.47% | 6 min | 10.2% |
| Frontier Airlines | 1,126 | 77.5% | 0.89% | -7 min | 7.3% |
United Airlines flew 44.2% of the 5,870 flights listed.
United Airlines arrived on time 16.6 percentage points more often than Southwest Airlines on this route.
Flights on this route
Flight numbers with at least 600 operations here and still on the schedule.
| Flight | Scheduled | Operations | On time |
|---|---|---|---|
| UA2269 United Airlines | 9:45 AM | 951 | 85.0% |
Weekly and seasonal patterns
By day of week
Saturday is historically the most reliable day and Friday the least, a gap of 6.3 percentage points.
By month
- Jan: 76.7%
- Feb: 76.2%
- Mar: 77.7%
- Apr: 75.1%
- May: 70.4%
- Jun: 67.3%
- Jul: 65.3%
- Aug: 66.7%
- Sep: 74.5%
- Oct: 77.4%
- Nov: 80.0%
- Dec: 79.8%
July is historically the weakest month and November the strongest, a spread of 14.7 percentage points.
Reliability over time
July 2023 – July 2026
- July 2023: 59.1% from 207 flights
- August 2023: 61.1% from 212 flights
- September 2023: 72.7% from 208 flights
- October 2023: 78.9% from 209 flights
- November 2023: 82.5% from 183 flights
- December 2023: 74.2% from 156 flights
- January 2024: 66.4% from 145 flights
- February 2024: 68.7% from 131 flights
- March 2024: 73.6% from 166 flights
- April 2024: 73.5% from 147 flights
- May 2024: 68.8% from 160 flights
- June 2024: 73.7% from 179 flights
- July 2024: 74.6% from 185 flights
- August 2024: 70.1% from 169 flights
- September 2024: 80.4% from 153 flights
- October 2024: 79.2% from 155 flights
- November 2024: 74.8% from 151 flights
- December 2024: 85.1% from 148 flights
- January 2025: 77.3% from 141 flights
- February 2025: 77.5% from 120 flights
- March 2025: 82.3% from 147 flights
- April 2025: 72.9% from 145 flights
- May 2025: 63.8% from 149 flights
- June 2025: 62.0% from 179 flights
- July 2025: 61.2% from 183 flights
- August 2025: 70.4% from 162 flights
- September 2025: 70.7% from 133 flights
- October 2025: 72.8% from 136 flights
- November 2025: 82.5% from 137 flights
- December 2025: 80.3% from 147 flights
- January 2026: 86.9% from 138 flights
- February 2026: 82.7% from 128 flights
- March 2026: 77.7% from 149 flights
- April 2026: 78.8% from 146 flights
- May 2026: 78.6% from 155 flights
- June 2026: 66.0% from 154 flights
- July 2026: 67.5% from 157 flights
Over the most recent 12 months (2025-08 to 2026-07), on-time arrivals averaged 76.0% against 73.4% in the 12 months before — improving by 2.6 percentage points.
Data and methodology
Calculated by FlyerIntel from 5,870 DEN → RDU flight records from the US DOT Bureau of Transportation Statistics, covering July 2023 – July 2026. Late means 15 or more minutes past scheduled arrival; cancelled and diverted flights are left out of on-time rates.
Full methodology · Data sources · Report a problem
Related research: How Long a Layover Needs to Be · Two Airlines on One Route · Best Time of Day to Fly From Major US Airports
Analysis last recomputed