67% of flights leaving Aspen (ASE) arrived on time over the past 12 months, 9 points worse than the national average of 76%. About 22 flights leave ASE on a typical day; 5.8% were cancelled. 67% pushed back from the gate on time, so most of the lateness is already there when the flight leaves the gate.
At a glance
- Best hour to fly: 8 a.m. (85% on time). Worst: 4 p.m. (53%).
- Best month: May (76%). Worst: February (58%).
- Most reliable airline here: United Airlines (70%), vs American Airlines at 59%.
- Biggest delay cause: severe weather (30% of delay minutes).
- Year on year: improving (62% → 67%).
How late?
The on-time rate treats a flight 20 minutes late the same as one 5 hours late. Here's the split for flights leaving ASE: when a flight was late, it was under 45 minutes late 37% of the time. About 1 in 7 flights landed an hour or more late, and 1 in 25 three hours or more; 5.8% were cancelled outright.
- On time or early67%
- 15–30 min late6.1%
- 30–60 min late6.2%
- 1–2 hours late6.8%
- 2–3 hours late3.6%
- 3+ hours late4.0%
- Diverted0.6%
- Cancelled5.8%
Share of all 8,137 scheduled flights, past 12 months, by arrival time against schedule.
Best time of day to fly out of ASE
Time of day matters more at ASE than almost anything else you control. Flights scheduled to leave at 8 a.m. arrived on time 85% of the time; at 4 p.m. it was 53%, a 32-point gap. Taken together, early departures (5–9 a.m.) ran 83% on time against 62% for the evening bank (5–10 p.m.). Early planes usually start the day at the airport, so they haven't had a chance to pick up delays elsewhere. By evening a late inbound aircraft, a crew running out of duty hours or an afternoon thunderstorm can push one late flight into the next. Cancellations cluster too: 4 p.m. departures were cancelled 10.7% of the time, against 5.8% overall.
Hour × month
Combine the two and the spread is wider still. The most reliable combination at ASE was a 10 a.m. departure in September (90% on time); the least, 3 p.m. in July (45%). If you can only move one thing, move the hour. Departure hour usually shifts the odds more than the month does.
Each cell: on-time rate for that departure hour in that calendar month, 2023–2026. Find your travel month, then look along the row for the greenest hour.
Best and worst months
February is the hardest month at ASE, with 58% of flights on time across 2023–2026; May is the best at 76%. Summer (June–August) runs 13 points worse than autumn: heavy schedules, peak loads and afternoon thunderstorms. Winter costs 16 points against autumn. Cancellations peak in March (10.1% of flights).
Airlines at ASE
United Airlines runs 63% of departures from ASE, so ASE is effectively its hub. When United Airlines has a bad day, so does the airport. Among airlines with at least 1,000 departures here, United Airlines was the most reliable (70% on time) and American Airlines the least (59%), a 11-point difference. On a route where both fly, that difference is worth more than a small fare gap.
| Airline | Departures | On time | Left on time | Cancelled | Typical arrival |
|---|---|---|---|---|---|
| United Airlines | 5,141 | 70% | 71% | 5.0% | −7 min |
| American Airlines | 2,210 | 59% | 57% | 8.4% | −4 min |
| Delta Air Lines | 786 | 72% | 71% | 3.6% | −9 min |
Why flights are late at ASE
Airlines report a cause for every flight that arrives 15 or more minutes late. At ASE, 30% of delay minutes came from severe weather: storms, snow and ice bad enough for the airline to report weather. Next is late-arriving aircraft at 25%. Of the 471 cancellations, 93% were blamed on weather.
The average taxi from gate to takeoff is 23 minutes, longer than at most large U.S. airports. Airlines pad schedules for it, but a long queue on a busy afternoon still eats into the buffer.
ASE vs nearby airports
| Airport | Distance | Departures | On time | Cancelled |
|---|---|---|---|---|
| ASE Aspen-Pitkin (Sardy ) | — | 8,137 | 67% | 5.8% |
| EGE Eagle | 29 mi | 3,958 | 71% | 1.8% |
| GUC Gunnison Crested Butte | 48 mi | 1,427 | 81% | 2.1% |
Month by month
Over the latest 12 months 67% of ASE departures were on time, against 62% in the 12 months before, an improvement of 6 points. The best recent month was May 2026 (87%); the worst, February 2026 (58%).
Worst cancellation days
The worst single day in the past year was Friday, Mar 6, 2026, when 83% of 40 scheduled departures were cancelled. Days like that are usually a major storm, a system outage or a holiday peak hitting bad weather. No average predicts them, so on a stormy forecast, check your airline's travel waivers.
| Date | Departures | Cancelled | On time |
|---|---|---|---|
| Mar 6, 2026 | 40 | 83% | 0% |
| Mar 15, 2026 | 40 | 65% | 28% |
| Feb 18, 2026 | 37 | 62% | 16% |
| Jan 24, 2026 | 34 | 56% | 24% |
| Feb 17, 2026 | 36 | 50% | 6% |
| Nov 30, 2025 | 12 | 50% | 8% |
| Dec 3, 2025 | 16 | 44% | 25% |
| Feb 20, 2026 | 40 | 43% | 20% |
| Apr 17, 2026 | 15 | 40% | 20% |
| Jan 25, 2026 | 34 | 38% | 38% |
Last flights of the day
The last flight of the day is a different bet. Across routes from ASE, each airline's final departure was cancelled 7.8% of the time, against 5.4% for its earlier flights (1.5× as often). Late in the day crews run short on duty hours, aircraft arrive late from elsewhere, and with no later flight to fold passengers into, cancelling is easier for the airline. 3.6% of last flights landed 3+ hours late. The riskiest last flight out was American Airlines to Chicago (11.8% cancelled).
| Last flight to | Airline | Leaves | Cancelled | 3h+ late | On time |
|---|---|---|---|---|---|
| ORD Chicago | American Airlines | 11:26 a.m. | 11.8% | 7.7% | 46% |
| SFO San Francisco | United Airlines | 9:40 a.m. | 9.3% | 3.4% | 54% |
| DFW Dallas | American Airlines | 2:20 p.m. | 8.3% | 3.5% | 61% |
| ATL Atlanta | Delta Air Lines | 7:30 a.m. | 7.9% | 3.5% | 57% |
| LAX Los Angeles | United Airlines | 7:15 p.m. | 9.3% | 2.0% | 73% |
| IAH Houston | United Airlines | 11:43 a.m. | 4.3% | 4.7% | 64% |
| DEN Denver | United Airlines | 6:12 p.m. | 7.4% | 1.5% | 65% |
| ORD Chicago | United Airlines | 12:39 p.m. | 5.2% | 3.5% | 57% |
Each airline's last scheduled departure of the day on a route, on days it flies the route at least twice; past 12 months. Riskiest first.
Tips for flying out of ASE
- Book the earliest departure you can live with. At ASE the 8 a.m. flights do best.
- Traveling in February? Leave extra slack for anything that can't move: cruises, weddings, the last connection of the day.
- Choosing between airlines? United Airlines has the better record here.
- Need to arrive tonight? Don't book the last flight out of ASE; the one before it leaves you a backup.
- Delayed already? Most delays at ASE come from severe weather. If your inbound plane is late, your flight will be too, whatever the board says.
Routes from ASE
Where you're going matters too. From ASE, the most reliable busy route was to Denver (DEN, 73% on time) and the least reliable to Chicago (ORD, 59%). Flights into congested airports inherit their delays: an air traffic program at the destination holds planes on the ground here.
Least reliable first. Routes with at least 365 flights a year.
| To | Flights | On time | Cancelled | Typical arrival |
|---|---|---|---|---|
| SFO San Francisco | 373 | 53% | 5.6% | +3 min |
| ORD Chicago | 1,179 | 59% | 5.9% | +1 min |
| DFW Dallas | 1,185 | 63% | 7.0% | −7 min |
| LAX Los Angeles | 1,228 | 69% | 6.7% | −12 min |
| IAH Houston | 639 | 72% | 4.5% | −7 min |
| DEN Denver | 2,742 | 73% | 5.0% | −8 min |
| ATL Atlanta | 450 | 73% | 3.6% | −8 min |
Flights into ASE
Arriving rather than leaving? These are the routes into Aspen-Pitkin (Sardy ), least reliable first. The weakest is from Chicago (55% on time).
| From | Flights | On time | Cancelled |
|---|---|---|---|
| ORD Chicago | 1,180 | 55% | 3.2% |
| DFW Dallas | 1,187 | 62% | 4.5% |
| SFO San Francisco | 376 | 63% | 2.4% |
| ATL Atlanta | 450 | 68% | 1.6% |
| DEN Denver | 2,742 | 69% | 5.1% |
| IAH Houston | 638 | 72% | 2.7% |
| LAX Los Angeles | 1,226 | 72% | 2.5% |
Questions about ASE delays
What is the best time to fly out of ASE?
Flights scheduled at 8 a.m.: over the past year 85% of ASE departures at that hour arrived on time, against 53% at 4 p.m., the worst hour.
What month has the most flight delays at ASE?
February (58% on time). May is the best month (76%).
Which airline is most on time at ASE?
United Airlines: 70% of its ASE departures arrived on time over the past year. American Airlines had the weakest record at 59%.
Why are flights delayed at ASE?
The biggest cause was severe weather (30% of delay minutes): storms, snow and ice bad enough for the airline to report weather. Then late-arriving aircraft (25%).
How often are flights cancelled at ASE?
5.8% of scheduled departures over the past 12 months, peaking in March at 10.1%.
Hours are scheduled local departure times. "On time" means arriving less than 15 minutes late at the destination; cancelled and diverted flights count as not on time. Method.