Carrier route record
UAMKE→DEN
United Airlines · Milwaukee to Denver
- Flights
- 742
- Period
- July 2025 to June 2026
- Share of route
- 32%
- Carriers
- 4
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with United Airlines.
United on MKE to DEN lands a B+, about a point worse than the national rate of 77.6%. About one flight in four arrives 15 minutes late or worse, and those flights are late by about an hour on average. That is a workable record, not a spotless one. That rests on 742 flights, with a median arrival 2 minutes early.
The US average over the same twelve months is 77.6%, so there is little to separate United on MKE to DEN from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
76.6%
Arrivals under 15 minutes late, of 738 completed flights
Avg delay
63 min
Across delayed arrivals only, not all flights
Cancelled
0.13%
National rate is 1.81%
Whole route
78.1%
Every carrier on MKE to DEN, 2,342 flights
These figures cover 742 flights between July 2025 and June 2026. The median arrival is 2 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.
Carrier by carrier
United against every carrier on MKE to DEN
United flew 742 of the 2,342 flights on MKE to DEN, about 32% of it. Its 76.6% on time is 2 points worse than the route as a whole, which runs 78.1%. Ranked by on-time rate it is number three of four carriers on the route, where the range runs from Southwest at 79.5% to Frontier at 71.7%. Two 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 |
|---|---|---|---|---|---|
| Southwest Airlines | 1,255 | 79.5% | 59 min | 0.64% | B+ |
| SkyWest Airlinesthin sample | 285 | 77.5% | 65 min | 0.35% | B+ |
| United Airlines (this page) | 742 | 76.6% | 63 min | 0.13% | B+ |
| Frontier Airlinesthin sample | 60 | 71.7% | 91 min | 0.00% | C+ |
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 30 points, against half a point between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am—
- 8am–11am317 flights79.7%
- 11am–2pm—
- 2pm–5pm364 flights78.2%
- 5pm–8pm61 flights50.0%
- 8pm–5am—
Scale runs 40% to 85%. Rows with fewer than 30 flights show a dash.
The 5pm–8pm window is where this operation falls apart: 50.0% on time, against 79.7% for the 8am–11am 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 2pm–5pm window is the busiest, with 364 flights scheduled in it.
Across the year
United on MKE to DEN through the year
August is the worst month at 63.8% on time, 29 points below November, the best at 93.2%. 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. August was the busiest month here, with 81 flights.
Across the week, Tuesday is the strongest day at 80.4% on time and Monday the weakest at 73.4%. 7 points is a smaller lever than departure hour, but it is free.
Delay causes
Why United runs late on this route
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 11,000 reported delay minutes.
- 41%National Airspace System
- 34%Carrier
- 18%Late-arriving aircraft
- 7%Extreme weather
41% of delay minutes are charged to the National Airspace System: air traffic volume, runway configuration, ground stops. No carrier can price its way out of that, which is why airport choice moves the number here more than carrier choice does. That is 4,499 minutes out of 11,000, against a national NAS share of 21%. The split is drawn from 10,943 reported delay minutes.
Cancellations are rare at 0.13%, below the national 1.81% 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
7.6% of arrivals land an hour or more late, close to the national 8.1%. That is the figure that decides a connection, and it says a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last about an hour, which a normal layover absorbs.
The 896 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. It is also long enough that the aircraft usually flies three or four legs a day rather than six, which slows how fast delay compounds.
The return leg is a different operation and performs like one: it runs 80.5% on time across 741 flights, 4 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 4 points of difference.
One caution: this is a thin sample. 742 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 MKE to DEN
Put together: treat all of this as provisional. 742 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 76.6% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 738 completed flights over 12 months sit behind that.
Related
Where to go next
- MKE to DEN, every carrier
- United on DEN to MKE, the return leg
- Southwest Airlines on MKE to DEN79.5%
- SkyWest Airlines on MKE to DEN77.5%
- United Airlines network-wide record
- Denver International (DEN) delay statistics
- The best time of day to fly, according to 7.04 million flight records
- Worst months to fly in the US, ranked by the data
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.