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Route · STL → DEN · 2020–2025 BTS data

St. Louis to Denver

According to PlainFlights' route traffic ranking (BTS On-Time Performance total flights), STL to DEN (St. Louis to Denver) ranks #310 of 4927 tracked domestic routes by total flights (most flights = #1).

Data updated 2026-06-13

79.9%
On-time
+0.9 pts
vs US avg
71 min
Delay when late
20,999
Flights
#310 of 4927
Corpus placement

Cancelled

0.9%

Best Month

Oct 2024 87%

Worst Month

May 2024 66%

Distance

770 mi

Carriers

27

Monthly Performance

Recent 24 months of route data.

Period Flights Delayed Cancelled Diverted Carriers
Dec 2025 266 82 0 1 WN,F9,UA
Nov 2025 275 49 1 0 UA,F9,WN
Oct 2025 334 66 0 0 OO,UA,WN,F9
Sep 2025 326 72 0 1 UA,WN,OO,F9
Aug 2025 330 96 0 3 OO,WN,F9,UA
Jul 2025 352 118 5 5 OO,UA,WN,F9
Jun 2025 339 113 0 4 OO,UA,WN,F9
May 2025 317 93 2 1 OO,UA,WN,F9
Apr 2025 284 91 2 0 F9,UA,WN
Mar 2025 293 59 0 0 UA,WN,F9
Feb 2025 252 49 0 0 UA,WN,F9
Jan 2025 272 44 17 0 UA,WN,F9
Dec 2024 308 46 1 0 F9,UA,WN
Nov 2024 297 40 2 0 UA,WN,F9
Oct 2024 325 41 0 0 UA,WN,F9
Sep 2024 307 39 1 0 WN,UA,F9
Aug 2024 322 70 3 0 F9,WN,UA
Jul 2024 356 97 6 0 F9,UA,WN
Jun 2024 344 99 0 1 F9,UA,WN
May 2024 348 119 0 1 F9,UA,WN
Apr 2024 337 64 5 0 F9,UA,WN
Mar 2024 340 59 8 0 F9,UA,WN
Feb 2024 289 53 2 0 F9,UA,WN
Jan 2024 310 66 10 1 F9,WN,OO,UA

STL–DEN seasonal on-time pattern

Best: November (87.3%) · weakest: July (70.9%)

70%75%80%85%90% JanFebMarAprMayJunJulAugSepOctNovDec 80.9%

Strongest calendar month

November

87.3% on-time · ~289 flights/mo

Busiest calendar month

August

~331 flights/mo avg

Weakest calendar month

July

70.9% on-time · ~326 flights/mo

Cancellation Rate

0.9%

65 of 7,523 flights

Diversion Rate

0.2%

18 of 7,523 flights

Origin-hub reliability standing

Mid-pack among STL departures

From STL, this corridor sits with 45 other 75–85% on-time routes out of 51 tracked departures, not the hub's reliability leaders (5 at ≥85%) and not the softest ( 1 below 75%). Destination: Denver · fleet on-time rank #3208 of 4927.

What the Data Says About STL to DEN

20,999 tracked flights put the STL to DEN pairing (St. Louis to Denver) at a 79.9% on-time rate, squarely in line with the wider network. Delays that do occur run 71.2 minutes on average. Across the 770-mile route and its 27 carriers, the trailing 24 months show 0.9% cancelled and 0.2% diverted (7,523 flights sampled).

The monthly split is wide on this route: Oct 2024 posted the strongest performance at 87% on-time, while May 2024 came in at just 66% - a 22-point swing worth factoring into travel timing.

On the multi-year calendar, STL–DEN peaks in November at 87.3% on-time while August carries the heaviest traffic (~331 flights per month) ; the softest month is July at 70.9%, a 16.4-point swing that repeats because the corridor's weather and holiday mix stays stable year to year.

Frequently Asked Questions

Where does STL to DEN rank among US routes by traffic?
According to PlainFlights' route traffic ranking, STL to DEN ranks #310 of 4927 tracked domestic routes by total flights (most flights = #1). That ordinal matches our busiest-routes listing (total_flights DESC). See /methodology#corpus-placement for the exact sort basis.
How often are flights delayed from STL to DEN?
Flights from St. Louis to Denver have a 79.9% on-time rate based on 20,999 flights. The average delay is 71.2 minutes. The best recent month was Oct 2024 with 87% on-time.
What is the cancellation rate for STL to DEN?
Over the last 24 months, 0.9% of flights on this route were cancelled (65 of 7,523 flights) and 0.2% were diverted.
How far is the flight from STL to DEN?
The flight distance from St. Louis (STL) to Denver (DEN) is approximately 770 miles. This route is served by 27 carriers.
When is the best time to fly from STL to DEN?
The best recent month for on-time performance was Oct 2024 (87% on-time). The worst was May 2024 (66% on-time). Consider booking during months with historically better performance.

Airports on this route

Data source

Data Source: Bureau of Transportation Statistics (BTS), On-Time Performance Data. Statistics reflect cumulative performance across all available reporting periods.

Using STL–DEN data

STL–DEN is mid-pack at 79.9% on-time; month and carrier mix move more than the corridor headline.

  • Compare STL and DEN airport profiles: delay causes and top routes differ even on the same corridor. STL airport
  • If your dates flex, November (87.3% on-time) beats July (70.9%) on this corridor. Seasonal chart
  • 4 other routes post a similar 79.9% on-time rate; compare before you commit to this pairing. Similar routes

On-time rate reflects the BTS historical average across all reporting carriers on this origin–destination pair, not any single flight or booking recommendation.

Data sourced from U.S. Department of Transportation Bureau of Transportation Statistics (BTS) On-Time Performance data. See our methodology for details. Retrieved and formatted by PlainFlights

Every figure on PlainFlights is rendered directly from BTS On-Time Performance data, no number is typed in by an editor. This page aggregates this specific route's on-time performance and monthly trend, live from the dataset. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.