DEN to STL flight delays & on-time performance
Nonstop flights from Denver International Airport to St. Louis Lambert International Airport · 770 miles · Aug 2025 – Jul 2026
No FAA-reported ground stops or delays at DEN or STL right now. Individual flights can still be delayed by the airline; check with your airline for your flight.
Key facts
- Flights from Denver (DEN) to St. Louis (STL) arrived on time 78% of the time in Aug 2025 – Jul 2026, in line with the national average.
- 0.5% were cancelled, and 7% arrived an hour or more late.
- Frontier Airlines was the most punctual airline here (84% on time); Southwest Airlines was the least (77%).
- Departures scheduled around 5am did best (96% on time); around 7pm did worst (50%).
- Tuesday was the most reliable day to fly (82% on time) and Sunday the least (74%).
- The largest source of delay minutes was late-arriving aircraft (55%).
Which airline is most on time from DEN to STL?
Ranked by on-time arrival rate. Regional airlines fly under their partner's brand (e.g. SkyWest for Delta Connection or United Express).
| Airline | On time | Cancelled | Avg delay | 1 hr+ late | Flights |
|---|---|---|---|---|---|
| Frontier Airlines | 84% | 0.3% | 9 min | 3.4% | 291 |
| SkyWest AirlinesRegional airline operating flights for United Express, Delta Connection, American Eagle and Alaska. | 82% | 0.9% | 8 min | 2.8% | 110 |
| United Airlines | 79% | 0.3% | 14 min | 7.9% | 1,100 |
| Southwest Airlines | 77% | 0.5% | 15 min | 8.1% | 2,194 |
Best time of day to fly
On-time arrival rate by scheduled departure hour (local time).
- 5am96%139 flights
- 6am94%294 flights
- 7am94%250 flights
- 8am95%73 flights
- 9am84%335 flights
- 10am86%406 flights
- 11am86%88 flights
- 12pm78%68 flights
- 1pm84%465 flights
- 2pm73%64 flights
- 3pm66%178 flights
- 4pm67%167 flights
- 5pm67%415 flights
- 6pm67%180 flights
- 7pm50%154 flights
- 8pm64%380 flights
Best day of the week
On-time arrival rate by day of departure.
- Monday76%0.4% cancelled
- Tuesday82%0.2% cancelled
- Wednesday81%0.9% cancelled
- Thursday76%0.0% cancelled
- Friday79%0.0% cancelled
- Saturday79%0.7% cancelled
- Sunday74%1.1% cancelled
On-time trend by month
Why flights are late
Share of delay minutes by cause, as reported by airlines to the DOT.
- Late-arriving aircraft55%
- Airline (crew, maintenance, cleaning, fueling)29%
- Air traffic control & airport congestion13%
- Extreme weather3%
- Security0%
Why flights are cancelled
Share of cancellations by reason.
- Extreme weather59%
- Airline (crew, maintenance, cleaning, fueling)29%
- Air traffic control & airport congestion12%
- Security0%
DEN to STL: common questions
- How often are DEN to STL flights on time?
- 78% of flights arrived less than 15 minutes late in Aug 2025 – Jul 2026, compared with 78% for all US flights.
- How often are flights from Denver to St. Louis cancelled?
- 0.5% of scheduled flights were cancelled (17 of 3,695).
- How long are typical delays?
- Across all flights the average arrival delay was 14 min (early arrivals count as zero). Flights that were late arrived 59 min behind schedule on average, and 7.5% of flights were an hour or more late.
- How long is taxi time at DEN?
- Flights on this route spent 18 min taxiing from the gate to takeoff on average.
Related routes
Return trip: STL to DEN — 76% on time
More flights from Denver
Data: U.S. DOT Bureau of Transportation Statistics, Aug 2025 – Jul 2026 (12 months). Latest month published by BTS: July 2026. Route: DEN → STL, nonstop flights by US airlines that report to the DOT. How we calculate this.