Carrier route record
F9MCI→DEN
Frontier Airlines · Kansas City to Denver
- Flights
- 261
- Period
- July 2025 to June 2026
- Share of route
- 6%
- Carriers
- 4
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Frontier Airlines.
Frontier on MCI to DEN sits in the middle of the pack with a B+. Close to three flights in four arrive on time by the DOT's definition, 2 points worse than the national rate of 77.6%. The late ones land close to two hours behind schedule. That rests on 261 flights. The strongest carrier on the route with a full sample, SkyWest Airlines, flew 374 at 89.5% on time.
SkyWest Airlines is the most reliable of the three carriers covered here at 89.5% on time across 374 flights.
Key figures
On time
75.8%
Arrivals under 15 minutes late, of 260 completed flights
Avg delay
119 min
Across delayed arrivals only, not all flights
Cancelled
0.38%
National rate is 1.81%
Whole route
76.1%
Every carrier on MCI to DEN, 4,274 flights
These figures cover 261 flights between July 2025 and June 2026. Beyond the headline rate, 13.5% of arrivals land a full hour or more behind schedule. That is the number that wrecks a connection, and it is not visible in an on-time percentage alone.
Carrier by carrier
Frontier against every carrier on MCI to DEN
Frontier flew 261 of the 4,274 flights on MCI to DEN, about 6% of it. Its 75.8% on time is about level with the route as a whole at 76.1%. Ranked by on-time rate it is number three of four carriers on the route, where the range runs from SkyWest at 89.5% to Southwest at 73.0%.
The choice of carrier is not cosmetic here. SkyWest Airlines arrives on time 89.5% of the time; Southwest Airlines manages 73.0%. Sample sizes sit next to every figure, because a two-point gap across 2,341 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| SkyWest Airlines | 374 | 89.5% | 104 min | 0.27% | A+ |
| United Airlines | 1,298 | 77.8% | 61 min | 0.54% | B+ |
| Frontier Airlines (this page)thin sample | 261 | 75.8% | 119 min | 0.38% | B+ |
| Southwest Airlines | 2,341 | 73.0% | 58 min | 0.73% | C+ |
The spread between SkyWest and Southwest is 17 points, wide enough that it should decide the booking. On a hundred trips that is 17 more arrivals inside the on-time window.
Flight by flight
Frontier flight numbers on MCI to DEN
Departure window
When Frontier runs best on this route
Departure time is the single lever a traveller controls, and it moves the odds more than most people expect. Each bar below is the on-time rate for flights scheduled to leave inside that window, across 261 flights.
- 5am–8am—
- 8am–11am—
- 11am–2pm25 flights—
- 2pm–5pm82 flights74.4%
- 5pm–8pm24 flights—
- 8pm–5am130 flights77.5%
Scale runs 65% to 85%. Rows with fewer than 30 flights show a dash.
The 8pm–5am window is the strongest at 77.5% on time. The full set of windows spans 3 points.
Across the year
Frontier on MCI to DEN through the year
- Jul–Sep 202545 flights57.8%
- Oct–Dec 202573 flights80.8%
- Jan–Mar 202660 flights79.7%
- Apr–Jun 202683 flights78.3%
Scale runs 50% to 85%. Rows with fewer than 30 flights show a dash.
Monthly volumes are too low here to break the year into twelve reliable readings. What the twelve-month total says is 75.8% on time across 261 flights.
Frontier on MCI to DEN did not run the same all year. Its best quarter was Oct–Dec 2025 at 80.8% on time and its weakest Jul–Sep 2025 at 57.8%, a swing of 23 points on roughly 65 flights a quarter. The twelve-month rate averages over that, so if you are flying in a weak quarter the quarter's own figure is the better guide.
Across the week, Thursday is the strongest day at 83.8% on time and Monday the weakest at 63.5%. 20 points is a smaller lever than departure hour, but it is free.
Delay causes
Why Frontier runs late on this route
One category carries most of the weight here. Late-arriving aircraft accounts for 54% of the 7,510 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.
- 54%Late-arriving aircraft
- 25%Carrier
- 20%National Airspace System
- 1%Extreme weather
54% 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 7,510 reported delay minutes here, that single category outweighs weather by 54 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 7,510 reported delay minutes.
Cancellations are rare at 0.38%, 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
For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 13.5% of arrivals land a full hour or more behind schedule, against 8.1% 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.
The 533 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 81.5% on time across 261 flights, 6 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 6 points of difference.
One caution: this is a thin sample. 261 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 Frontier on MCI to DEN
Put together: treat all of this as provisional. 261 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 75.8% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 260 completed flights over 12 months sit behind that.
Related
Where to go next
- MCI to DEN, every carrier
- Frontier on DEN to MCI, the return leg
- SkyWest Airlines on MCI to DEN89.5%
- United Airlines on MCI to DEN77.8%
- Southwest Airlines on MCI to DEN73.0%
- Frontier Airlines network-wide record
- Kansas City International (MCI) delay statistics
- Denver International (DEN) delay statistics
- Same route, different airline: where the carrier you pick matters most
- Why the first flight of the morning is statistically safest
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.