Route reliability record
DEN→GUC
Denver to Gunnison
- Flights
- 994
- Period
- September 2025 to August 2026
- Distance
- 152 mi
- Carriers
- 1
This route lands a B+, 3 points better than the national rate of 77.3%. About one flight in five arrives 15 minutes late or worse, and those flights are late by an hour and a half on average. That rests on 994 DEN to GUC flights, with a median arrival 7 minutes early.
The US average over the same twelve months is 77.3%, so there is little to separate this route from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
80.5%
Arrivals under 15 minutes late, of 984 completed flights
Avg delay
93 min
Across delayed arrivals only, not all flights
Cancelled
0.80%
National rate is 1.89%
Best carrier
SkyWest
80.5% on time across 994 flights
These figures cover 994 flights between September 2025 and August 2026. The median arrival is 7 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
Which airline is most reliable on DEN to GUC
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 |
|---|---|---|---|---|---|
| SkyWest Airlines | 994 | 80.5% | 93 min | 0.80% | B+ |
Flight by flight
Flights on DEN to GUC
The flight numbers below flew this route at least 250 times in the period, busiest first. Each has its own record, with its schedule and delay causes.
Timetable by Aviasales, a Travelpayouts partner. Booking through it may earn this site a commission at no cost to you; it changes no figure here.
Best ways to make this trip
The most reliable ways to fly Denver to Gunnison
Every airline on this route and on the routes between nearby airports, ranked by how often a scheduled flight actually operated and arrived on time. 3 of the top 4 use a different airport at one end.
| Option | Airline | Success | On time | Cancelled | Best departure | Most punctual flight |
|---|---|---|---|---|---|---|
| 1. DEN → GUCDenver to Gunnison | SkyWest Airlines | 79.9% | 80.5% | 0.80% | 11am–2pm, Tue | OO 5343 11:30 |
| 2. DEN → MTJDenver to Montrose | United Airlines | 75.7% | 75.8% | 0.11% | 11am–2pm, Wed | UA 1772 11:20 |
| 3. DEN → MTJDenver to Montrose | Southwest Airlines | 71.8% | 72.0% | 0.23% | 8am–11am, Wed | — |
| 4. DEN → ASEDenver to Aspen | SkyWest Airlines | 70.4% | 74.2% | 5.11% | 5am–8am, Tue | OO 5782 09:50 |
Success is the share of scheduled flights that operated and arrived less than 15 minutes late, so a cancelled flight counts against it. “(route)” means the best time comes from every carrier on the route rather than this airline alone.
Departure window
The best time of day to leave
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 13 points, against half a point between the best and worst carrier.
- 5am–8am—
- 8am–11am—
- 11am–2pm631 flights85.2%
- 2pm–5pm—
- 5pm–8pm363 flights72.3%
- 8pm–5am—
Scale runs 65% to 90%. Rows with fewer than 30 flights show a dash.
The best window here is not the first bank but the 11am–2pm slot at 85.2% on time, ahead of 5pm–8pm at 72.3%. Where the curve peaks mid-day rather than at dawn, the constraint is usually congestion at one end rather than the aircraft's own rotation. The 11am–2pm window is the busiest, with 631 flights scheduled in it.
Explore
Filter DEN to GUC by airline, time, month and day
Pick a breakdown and a carrier. The dashed mark on each row is the same slice for every US flight.
On DEN to GUC, the best departure window is 11am–2pm at 85.2% on time and the worst is 5pm–8pm at 72.3%, a wide gap of 12.9 points. All US flights leaving 11am–2pm ran 78.3%.
- 5–8am—
- 8–11am—
- 11am–2pm85.2%
- 2–5pm—
- 5–8pm72.3%
- 8pm–5am—
best all US flightsScale 60% to 95%. Cells under 30 flights show a dash.
Across the year
When delays peak on this route
This route's year swings by 18 points from best month to worst, which is wide. An annual average tells you very little about the week you are actually flying, so read the strip rather than the headline if your dates are fixed.
July is the worst month at 70.7% on time, 18 points below March, the best at 88.6%. 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 93 flights.
Across the week, Tuesday is the strongest day at 84.4% on time and Monday the weakest at 77.8%, a spread of 7 points.
Delay causes
Why this route gets delayed
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 18,000 reported delay minutes.
- 39%Carrier
- 35%Late-arriving aircraft
- 16%National Airspace System
- 10%Extreme weather
35% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 18,000 reported delay minutes here, that single category outweighs weather by 4 to one. The split is drawn from 17,804 reported delay minutes.
The largest share of delay minutes, 39%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. It accounts for 6,961 of the 18,000 delay minutes reported here.
Cancellations are rare at 0.80%, 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 actually costs
7.6% 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.
At 152 miles this is a short hop, and stage length matters more than it looks. A flight this short spends under two hours in the air, which leaves almost nothing to claw back a late pushback with. Delay here is decided on the ground, in the turn, which is why the 11am–2pm window matters as much as it does.
The return leg is a different operation and performs like one: it runs 83.6% on time across 994 flights, 3 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 3 points of difference.
One caution: this is a thin sample. 994 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.
Work out the risk of missing a connection in GUC after this flight
What to do with this
Booking this route
Put together: treat all of this as provisional. 994 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 80.5% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 984 completed flights over 12 months sit behind that.
Common questions
DEN to GUC questions
How often is DEN to GUC delayed?
About one flight in five arrives at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 19.5% of the 994 flights in this analysis, against 22.7% nationally. Delayed flights are late by an hour and a half on average.
How reliable is DEN to GUC compared with the rest of the country?
80.5% of flights arrive on time here against a national 77.3%, a difference of 3 points in its favour. That is worth a B+ on this site's grading scale.
What time of day has the fewest delays on DEN to GUC?
The 11am–2pm departure window is the strongest at 85.2% on time. The 5pm–8pm window is the weakest at 72.3%, 13 points behind. Later departures inherit delays from earlier flights the same aircraft has already flown, which is why the curve slopes the way it does.
How bad are July delays on DEN to GUC?
July is the weakest month at 70.7% on time, compared with 88.6% in March. Across the year that is 18 points between the best and worst months. Moving flexible dates out of that month is one of the few things that reliably helps.
Related
Where to go next
- GUC to DEN — the return legseparate record
- Denver International (DEN) delay statistics
- DEN to PHX, a related route75.6%
- DEN to SLC, a related route78.2%
- DEN to LAX, a related route78.7%
- SkyWest Airlines on-time record80.5%
- Flying to ski country: which routes into the mountains run on time
- Why the first flight of the morning is statistically safest
Direction matters. DEN to GUC and GUC to DEN are scored separately because they are separate operations, with different departure banks and different aircraft. Compare the return leg.
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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.