Carrier route record

F9DSM→DEN

Frontier Airlines · Des Moines to Denver

Flights: 153
Period: July 2025 to June 2026
Share of route: 7%
Carriers: 4

Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Frontier Airlines.

Frontier on DSM to DEN lands a B+, level with the national rate of 77.6%. Roughly one flight in five arrives 15 minutes late or worse, and those flights are late by close to two hours on average. That is a workable record, not a spotless one. That rests on 153 flights. The strongest carrier on the route with a full sample, SkyWest Airlines, flew 936 at 90.0% on time.

SkyWest Airlines is the most reliable of the three carriers covered here at 90.0% on time across 936 flights.

On time

77.8%

Arrivals under 15 minutes late, of 153 completed flights

Avg delay

102 min

Across delayed arrivals only, not all flights

Cancelled

0.00%

National rate is 1.81%

Whole route

83.0%

Every carrier on DSM to DEN, 2,329 flights

These figures cover 153 flights between July 2025 and June 2026. Beyond the headline rate, 9.2% 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 DSM to DEN

Frontier flew 153 of the 2,329 flights on DSM to DEN, about 7% of it. Its 77.8% on time is 5 points worse than the route as a whole, which runs 83.0%. Ranked by on-time rate it is number three of four carriers on the route, where the range runs from SkyWest at 90.0% to United at 74.2%.

The choice of carrier is not cosmetic here. SkyWest Airlines arrives on time 90.0% of the time; United Airlines manages 74.2%. Sample sizes sit next to every figure, because a two-point gap across 681 flights means less than a ten-point one.

On-time performance by carrier on DSM to DEN
Airline	Flights	On time	Avg delay	Cancelled	Grade
SkyWest Airlines	936	90.0%	101 min	0.75%	A+
Southwest Airlines	559	83.4%	72 min	0.54%	B+
Frontier Airlines (this page)thin sample	153	77.8%	102 min	0.00%	B+
United Airlines	681	74.2%	77 min	0.59%	C+

The spread between SkyWest and United is 16 points, wide enough that it should decide the booking. On a hundred trips that is 16 more arrivals inside the on-time window.

Departure window

When Frontier runs best on this route

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 48 points, against 16 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am—
8am–11am—
11am–2pm—
2pm–5pm82 flights91.5%
5pm–8pm30 flights43.3%
8pm–5am41 flights75.6%

Scale runs 35% to 95%. Rows with fewer than 30 flights show a dash.

The 5pm–8pm window is where this operation falls apart: 43.3% on time, against 91.5% for the 2pm–5pm 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 82 flights scheduled in it.

Across the year

Frontier on DSM to DEN through the year

Jul–Sep 202538 flights57.9%
Oct–Dec 202549 flights89.8%
Jan–Mar 202635 flights71.4%
Apr–Jun 202631 flights90.3%

Scale runs 50% to 95%. 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 77.8% on time across 153 flights.

Frontier on DSM to DEN did not run the same all year. Its best quarter was Apr–Jun 2026 at 90.3% on time and its weakest Jul–Sep 2025 at 57.9%, a swing of 32 points on roughly 38 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.

Delay causes

Why Frontier 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 3,479 reported delay minutes.

Late-arriving aircraft
40%
Carrier
31%
National Airspace System
19%
Extreme weather
9%

40% 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 3,479 reported delay minutes here, that single category outweighs weather by 4 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 3,479 reported delay minutes.

Cancellations are rare at 0.00%, below the national 1.81% and low enough to earn the plus on the grade. Almost no flights are 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. 9.2% 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 589 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 runs 79.7% on time across 153 flights, within 2 points of this direction. The two legs are scored separately because they usually differ; on this city pair they happen not to.

One caution: this is a thin sample. 153 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 DSM to DEN

Put together: treat all of this as provisional. 153 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 77.8% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 153 completed flights over 12 months sit behind that.

Where to go next

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.

Key figures