Carrier route record
UADEN→GTF
United Airlines · Denver to Great Falls
- Flights
- 527
- Period
- September 2025 to August 2026
- Share of route
- 72%
- Carriers
- 2
Historical statistics for September 2025 to August 2026, not live status. For today’s flights, check with United Airlines.
United on DEN to GTF sits in the middle of the pack with a C+. Close to three flights in four arrive on time by the DOT's definition, 4 points worse than the national rate of 77.3%. The late ones land a little over an hour behind schedule. That rests on 527 flights, with a median arrival 4 minutes early.
The US average over the same twelve months is 77.3%, so there is little to separate United on DEN to GTF from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
73.5%
Arrivals under 15 minutes late, of 525 completed flights
Avg delay
71 min
Across delayed arrivals only, not all flights
Cancelled
0.38%
National rate is 1.89%
Whole route
76.9%
Every carrier on DEN to GTF, 728 flights
These figures cover 527 flights between September 2025 and August 2026. Beyond the headline rate, 10.9% of arrivals land a full hour or more behind schedule, against 8.3% nationally.
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Carrier by carrier
United against every carrier on DEN to GTF
United flew 527 of the 728 flights on DEN to GTF, most of the route. Its 73.5% on time is 3 points worse than the route as a whole, which runs 76.9%. Ranked by on-time rate it is last of two carriers on the route, where the range runs from SkyWest at 85.9% to United at 73.5%. 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 |
|---|---|---|---|---|---|
| SkyWest Airlinesthin sample | 201 | 85.9% | 67 min | 1.00% | A |
| United Airlines (this page) | 527 | 73.5% | 71 min | 0.38% | C+ |
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.
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 23 points, against half a point between the best and worst carrier.
- 5am–8am—
- 8am–11am—
- 11am–2pm291 flights83.7%
- 2pm–5pm—
- 5pm–8pm234 flights60.7%
- 8pm–5am2 flights—
Scale runs 50% to 90%. Rows with fewer than 30 flights show a dash.
The 5pm–8pm window is where this operation falls apart: 60.7% on time, against 83.7% for the 11am–2pm 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 291 flights scheduled in it.
Across the year
United on DEN to GTF through the year
June is the worst month at 53.3% on time, 40 points below November, the best at 93.5%. 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. May was the busiest month here, with 62 flights.
Across the week, Tuesday is the strongest day at 80.8% on time and Wednesday the weakest at 66.2%, a spread of 15 points.
Arrival by arrival
How late United on DEN to GTF runs when it is late
The 139 late arrivals split 40 under half an hour, 42 between 30 and 60 minutes, and 57 an hour or more.
- 15+ min early104 flights19.8%
- Within 15 min282 flights53.7%
- 15–29 min late40 flights7.6%
- 30–59 min late42 flights8.0%
- 1–2 hours late34 flights6.5%
- 2+ hours late23 flights4.4%
Scale runs 0% to 100%.
Share of 525 completed flights by arrival against schedule.
21 of 140 late departures made up the time and arrived on time, 15% of them. 20 flights left on time and still arrived late.
The worst days
Worst days for United on DEN to GTF
The latest arrival of the period was on 23 August 2026, 9 hours 57 minutes behind schedule; most of its delay minutes were filed as carrier-caused (crew, maintenance, fuelling, baggage). Three of the five worst days fell in August 2026.
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 23 August 2026 | 9 hours 57 minutes | Carrier |
| 21 July 2026 | 5 hours 10 minutes | Carrier |
| 3 August 2026 | 3 hours 38 minutes | Late-arriving aircraft |
| 7 August 2026 | 3 hours 30 minutes | Late-arriving aircraft |
| 23 July 2026 | 3 hours 28 minutes | Late-arriving aircraft |
Delay causes
Why United runs late on this route
Late-arriving aircraft accounts for 57% of the 9,869 delay minutes carriers reported here, and the remaining four split what is left.
- 57%Late-arriving aircraft
- 30%Carrier
- 10%National Airspace System
- 3%Extreme weather
57% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 9,869 reported delay minutes here, that single category outweighs weather by 17 to one. The split is drawn from 9,869 reported delay minutes.
Cancellations are rare at 0.38%, 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
10.9% of arrivals land a full hour or more behind schedule, against 8.3% nationally. Ninety minutes is the honest minimum for a connection here, and two hours if the onward flight is on a separate ticket.
The 623 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 84.1% on time across 527 flights, 11 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 11 points of difference.
One caution: this is a thin sample. 527 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 DEN to GTF
Put together: treat all of this as provisional. 527 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 73.5% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 525 completed flights over 12 months sit behind that.
Related
Where to go next
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.