Airport month record
DENJUL
Denver International in July 2025
- Departures
- 29,433
- Month
- July 2025
- National, same month
- 71.1%
- Carriers
- 9
Historical statistics for July 2025, not live status or a forecast for this year’s July. For today’s conditions at DEN, see live FAA status.
DEN in July draws a D. Roughly one flight in three arrives at least 15 minutes late, and the typical late arrival is a little over an hour behind schedule. Build slack into anything you connect to. That rests on 29,433 flights, of which Delta Air Lines flew 1,119 at 72.6% on time.
Delta Air Lines is the most reliable of the six carriers covered here at 72.6% on time across 1,119 flights.
Key figures
On time
63.0%
Arrivals under 15 minutes late, of 28,827 completed departures
Avg delay
77 min
Across delayed arrivals only, not all flights
Cancelled
1.48%
Nationally in July: 2.45%
Whole year
76.3%
DEN across all twelve months
These figures cover 29,433 departures from Denver International in July 2025. On time means an arrival less than 15 minutes after the scheduled gate time, the DOT's threshold, and the national comparison uses every US departure in the same month rather than the whole year.
Against the year
July next to DEN's other months
Against DEN's own year, July ran 13 points worse than the twelve-month rate of 76.3%, which makes it the worst of the twelve months in the data. Cancellations are where July stands out: 1.48% of scheduled departures were called off, 1.9 times the airport's rate across the year.
| Month | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| July 2025 (this page) | 29,433 | 63.0% | 77 min | 1.48% | D |
| August 2025 | 28,084 | 70.1% | 69 min | 0.73% | C+ |
| September 2025 | 26,548 | 79.4% | 54 min | 0.12% | B+ |
| October 2025 | 27,763 | 80.8% | 52 min | 0.13% | B+ |
| November 2025 | 25,280 | 84.7% | 62 min | 1.44% | B |
| December 2025 | 26,026 | 74.3% | 68 min | 0.64% | C+ |
| January 2026 | 24,484 | 82.3% | 60 min | 1.69% | B |
| February 2026 | 23,046 | 82.4% | 69 min | 0.88% | B+ |
| March 2026 | 27,089 | 76.8% | 72 min | 1.50% | B |
| April 2026 | 25,345 | 82.5% | 56 min | 0.27% | B+ |
| May 2026 | 27,406 | 76.4% | 58 min | 0.28% | B+ |
| June 2026 | 28,634 | 67.1% | 64 min | 0.41% | C+ |
Departure window
The best time of day to leave DEN in July
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 47 points, against 15 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am2,714 flights87.6%
- 8am–11am5,578 flights80.3%
- 11am–2pm6,202 flights72.9%
- 2pm–5pm4,520 flights56.8%
- 5pm–8pm6,021 flights40.4%
- 8pm–5am4,398 flights48.0%
Scale runs 30% to 95%. Rows with fewer than 30 flights show a dash.
The 5pm–8pm window is where this operation falls apart: 40.4% on time, against 87.6% for the 5am–8am slot. By evening the aircraft flying these rotations have absorbed a full day of small delays and there is no slack left to recover in. The 11am–2pm window is the busiest, with 6,202 flights scheduled in it.
Across the week, Saturday is the strongest day at 68.1% on time and Thursday the weakest at 57.0%. 11 points is a smaller lever than departure hour, but it is free.
Carrier by carrier
Which airlines ran best at DEN in July
The choice of carrier is not cosmetic here. Delta Air Lines arrives on time 72.6% of the time; Southwest Airlines manages 57.3%. Sample sizes sit next to every figure, because a two-point gap across 8,693 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| United Airlines | 9,646 | 62.4% | 79 min | 1.02% | D |
| Southwest Airlines | 8,693 | 57.3% | 69 min | 1.35% | D |
| SkyWest Airlines | 6,702 | 68.7% | 83 min | 1.79% | C |
| Frontier Airlines | 1,956 | 66.7% | 79 min | 1.53% | C |
| Delta Air Lines | 1,119 | 72.6% | 91 min | 2.32% | C |
| American Airlines | 802 | 65.9% | 110 min | 3.37% | C− |
| Alaska Airlinesthin sample | 268 | 56.1% | 69 min | 2.24% | D |
| JetBlue Airwaysthin sample | 149 | 56.2% | 70 min | 6.04% | D− |
| Allegiant Airthin sample | 84 | 55.0% | 154 min | 4.76% | D− |
American Airlines cancels 3.4% of what it schedules here, the highest in the table. A cancelled flight never appears in an on-time rate, so read that column alongside the punctuality one rather than after it.
Route by route
Busiest routes out of DEN in July
| Route | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| DEN to SLC · Salt Lake City | 687 | 59.3% | 74 min | 1.46% | D |
| DEN to LAX · Los Angeles | 679 | 70.2% | 73 min | 1.18% | C |
| DEN to SEA · Seattle | 670 | 63.4% | 69 min | 1.64% | D |
| DEN to PHX · Phoenix | 658 | 61.2% | 73 min | 1.52% | D |
| DEN to ORD · Chicago | 583 | 56.9% | 101 min | 2.74% | D |
| DEN to MSP · Minneapolis | 570 | 64.6% | 84 min | 1.23% | D |
| DEN to LAS · Las Vegas | 561 | 62.6% | 78 min | 1.07% | D |
| DEN to DFW · Dallas-Fort Worth | 540 | 62.5% | 100 min | 2.04% | D |
| DEN to ATL · Atlanta | 525 | 70.3% | 82 min | 0.76% | C+ |
| DEN to COS · Colorado Springs | 466 | 58.4% | 80 min | 3.65% | D− |
| DEN to SFO · San Francisco | 464 | 55.8% | 70 min | 2.37% | D |
| DEN to PDX · Portland | 461 | 63.8% | 70 min | 2.17% | D |
| DEN to SAN · San Diego | 458 | 65.1% | 67 min | 0.87% | C+ |
| DEN to MCO · Orlando | 438 | 66.7% | 65 min | 0.68% | C+ |
| DEN to AUS · Austin | 437 | 57.5% | 71 min | 1.83% | D |
| DEN to BOS · Boston | 427 | 66.1% | 76 min | 1.17% | C |
| DEN to LGA · New York | 409 | 58.9% | 72 min | 5.13% | D− |
| DEN to IAH · Houston | 402 | 56.8% | 74 min | 0.00% | D+ |
| DEN to MCI · Kansas City | 387 | 61.7% | 76 min | 0.78% | D+ |
| DEN to SMF · Sacramento | 384 | 63.3% | 78 min | 1.30% | D |
| DEN to BNA · Nashville | 370 | 59.3% | 76 min | 1.08% | D |
| DEN to IAD · Washingtonthin sample | 361 | 64.3% | 80 min | 1.11% | D |
| DEN to STL · St. Louisthin sample | 352 | 66.3% | 76 min | 0.00% | C+ |
| DEN to SNA · Santa Anathin sample | 347 | 66.6% | 53 min | 1.15% | C |
| DEN to OKC · Oklahoma Citythin sample | 321 | 64.0% | 71 min | 0.93% | D+ |
Delay causes
What held DEN up in July
One category carries most of the weight here. Late-arriving aircraft accounts for 51% of the 825,000 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.
- 51%Late-arriving aircraft
- 28%Carrier
- 17%National Airspace System
- 5%Extreme weather
- 0%Security
51% 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 825,000 reported delay minutes here, that single category outweighs weather by 11 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 824,712 reported delay minutes.
Cancellations sit at 1.48% against a national 2.45%, which is ordinary. Diversions add another 0.57%.
For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 15.7% of arrivals land a full hour or more behind schedule, against 12.1% nationally. A 45-minute layover does not survive that, and no amount of walking quickly changes it. Ninety minutes is the honest minimum here, and two hours if the onward flight is on a separate ticket.
What to do with this
Flying from DEN in July
For a July trip through DEN: plan on this being one of the airport's harder months. The 5am–8am departures held up best at 87.6% on time, and with 15.7% of arrivals an hour or more late, a connection here deserves more slack than the same trip in November would.
Related
Where to go next
- Denver International (DEN), the whole year
- DEN in August70.1%
- DEN in September79.4%
- DEN in October80.8%
- DEN in November84.7%
- DEN in December74.3%
- DEN in January82.3%
- DEN in February82.4%
- DEN in March76.8%
- DEN in April82.5%
- DEN in May76.4%
- DEN in June67.1%
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.