Carrier route record

OODEN→STL

SkyWest Airlines · Denver to St. Louis

Flights: 141
Period: July 2025 to June 2026
Share of route: 4%
Carriers: 4

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

SkyWest on DEN to STL lands a B+, level with the national rate of 77.6%. Roughly one flight in four arrives 15 minutes late or worse, and those flights are late by roughly 50 minutes on average. That is a workable record, not a spotless one. That rests on 141 flights. The strongest carrier on the route with a full sample, United Airlines, flew 1,072 at 79.5% on time.

The US average over the same twelve months is 77.6%, so there is little to separate SkyWest on DEN to STL from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.

On time

77.0%

Arrivals under 15 minutes late, of 139 completed flights

Avg delay

52 min

Across delayed arrivals only, not all flights

Cancelled

0.71%

National rate is 1.81%

Whole route

78.1%

Every carrier on DEN to STL, 3,662 flights

These figures cover 141 flights between July 2025 and June 2026. Beyond the headline rate, 8.6% 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

SkyWest against every carrier on DEN to STL

SkyWest flew 141 of the 3,662 flights on DEN to STL, about 4% of it. Its 77.0% on time is about level with the route as a whole at 78.1%. Ranked by on-time rate it is number three of four carriers on the route, where the range runs from Frontier at 85.9% to Southwest at 76.4%. One of those carriers flew fewer than 365 flights here, so treat their positions as rough.

The two carriers here are closely matched: 3 points separate the best from the worst. At that spread, schedule and price are better tie-breakers than reliability. Sample sizes are shown so you can see which rows are worth weighing.

On-time performance by carrier on DEN to STL
Airline	Flights	On time	Avg delay	Cancelled	Grade
Frontier Airlinesthin sample	277	85.9%	47 min	0.36%	A+
United Airlines	1,072	79.5%	62 min	0.28%	B+
SkyWest Airlines (this page)thin sample	141	77.0%	52 min	0.71%	B+
Southwest Airlines	2,172	76.4%	58 min	0.41%	B+

No carrier stands out. United tops the table at 79.5%, 3 points clear of the bottom, which is inside the range this kind of sample moves year to year.

Departure window

When SkyWest 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 141 flights.

There are not enough flights in each departure window to split SkyWest's DEN to STL record by time of day without the percentages moving on noise. The headline rate of 77.0% is the reliable figure here.

Across the year

SkyWest on DEN to STL through the year

Jul–Sep 202592 flights69.2%
Oct–Dec 202525 flights—
Jan–Mar 202624 flights—

Scale runs 60% to 75%. 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 77.0% on time across 141 flights.

Split by quarter, SkyWest on DEN to STL logged 92 flights in Jul–Sep 2025, 25 flights in Oct–Dec 2025 and 24 flights in Jan–Mar 2026. Fewer than three of those quarters carried the 30 completed flights this site needs before printing a rate, so the 77.0% annual figure is the one to use.

Delay causes

Why SkyWest 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 1,676 reported delay minutes.

Late-arriving aircraft
34%
National Airspace System
33%
Extreme weather
21%
Carrier
12%

Extreme weather accounts for 21% of delay minutes, well above the single-digit share typical across the system. Weather delays are lumpy: they arrive as whole bad days rather than as a steady drag, so the monthly strip above is the more useful view of the risk. The national share is 6%, so this operation carries roughly 3.4 times the usual weather exposure. The split is drawn from 1,676 reported delay minutes.

33% 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 547 minutes out of 1,676, against a national NAS share of 21%.

Cancellations are rare at 0.71%, 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

8.6% 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 roughly 50 minutes, which a normal layover absorbs.

The 770 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 87.1% on time across 142 flights, 10 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 10 points of difference.

One caution: this is a thin sample. 141 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 SkyWest on DEN to STL

Put together: treat all of this as provisional. 141 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 77.0% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 139 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