Denver (DEN) to St Louis (STL) flights

Southwest Airlines, United Airlines, Frontier Airlines fly nonstop from Denver International Airport to St. Louis Lambert International Airport, with about 87 flights a week in July 2026. The 770-mile flight takes about 1h 58m gate to gate.

From

DEN

Denver

Denver International Airport

STL

St Louis

St. Louis Lambert International Airport

Distance: 770 mi · 1,239 km
Flight time: 1h 58m
Airlines: 3
Seats filled: 76%

Flights a week, July 2026

3,687 flights and 456,134 passengers in 12 months

Map data: Natural Earth. Lines follow the shortest (great-circle) path.

Airlines flying DEN to STL

Airline	Flights a week	Aircraft	Passengers (12 months)	Flight time
Southwest Airlines	53	Boeing 737 MAX 8, Boeing 737-700 / MAX 7, Boeing 737-800	267,668	1h 55m
United Airlines	28	Boeing 737-800, Airbus A319, Airbus A320-100/200	138,307	2h 3m
Frontier Airlines	7	Airbus A321, Airbus A320neo, Airbus A320-100/200	43,446	2h 4m
SkyWest AirlinesSeasonal or ended	n/a	Embraer E175	6,713	2h 6m

Airlines are the operating carrier: regional airlines such as SkyWest or Horizon often fly under a larger airline's brand.

DEN to STL flight schedule

21 flight numbers flew this route in August 2026, 5 of them almost daily. The first usually leaves at 6:35am and the last at 10:05pm. Times are local and can change; check with the airline before you book.

Flight	Departs	Arrives	Days flown in August 2026	On time (12 months)
WN 1694Southwest Airlines	6:35am	9:35am	12	100%
WN 1260Southwest Airlines	7:00am	10:00am	12	100%
WN 4334Southwest Airlines	7:25am	10:25am	4	n/a
WN 1965Southwest Airlines	8:05am	11:10am	12	95%
UA 652United Airlines	9:35am	12:40pm	31	86%
WN 127Southwest Airlines	11:05am	2:05pm	12	75%
WN 1695Southwest Airlines	11:15am	2:20pm	16	94%
WN 422Southwest Airlines	12:10pm	3:15pm	12	67%
UA 1639United Airlines	1:27pm	4:34pm	31	82%
WN 3286Southwest Airlines	3:35pm	6:35pm	4	n/a
WN 241Southwest Airlines	3:40pm	6:45pm	12	50%
F9 3302Frontier Airlines	4:10pm	7:23pm	25	83%
WN 2035Southwest Airlines	4:45pm	7:45pm	24	74%
UA 1422United Airlines	5:35pm	8:46pm	31	69%
WN 237Southwest Airlines	5:55pm	9:10pm	12	25%
WN 3449Southwest Airlines	6:50pm	9:55pm	16	44%
WN 3667Southwest Airlines	8:05pm	11:10pm	16	31%
UA 4778United Airlines · operated by SkyWest Airlines	8:25pm	11:40pm	9	n/a
UA 611United Airlines	8:25pm	11:31pm	6	n/a
UA 214United Airlines	8:45pm	11:57pm	10	57%
WN 4981Southwest Airlines	10:05pm	1:10am	4	n/a

Is DEN to STL on time?

From September 2025 to August 2026, 78% of 3,699 flights arrived within 15 minutes of schedule and 0.5% were cancelled. Flights leaving around 6am were the most punctual (95%), those around 8pm the least (62%). Most delay time was caused by late-arriving aircraft (56%).

Airline	Flights	On time	Average delay	Cancelled
Southwest Airlines	2,203	77%	15 min	0.5%
United Airlines	1,204	78%	16 min	0.4%
Frontier Airlines	292	83%	10 min	0.3%

Airlines as sold: flights operated by regional partners count under the airline on the ticket. Average delay is across all completed flights, early arrivals counted as zero.

On-time arrivals by departure time

Scheduled departure	Flights	On time
5am to 6am	127	95%
6am to 7am	276	95%
7am to 8am	245	94%
8am to 9am	85	97%
9am to 10am	323	87%
10am to 11am	395	86%
11am to 12pm	113	85%
12pm to 1pm	83	76%
1pm to 2pm	439	84%
3pm to 4pm	193	65%
4pm to 5pm	184	69%
5pm to 6pm	432	65%
6pm to 7pm	171	66%
7pm to 8pm	153	49%
8pm to 9pm	380	62%

Flights by month

Month	Flights	Passengers
August 2025	327	41,492
September 2025	325	41,474
October 2025	333	41,830
November 2025	273	33,697
December 2025	267	30,553
January 2026	251	30,018
February 2026	252	28,253
March 2026	319	39,841
April 2026	287	35,192
May 2026	314	40,119
June 2026	354	45,559
July 2026	386	48,219

Source: US Department of Transportation, T-100 Segment data, August 2025 to July 2026.