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Denver → Saint Louis

Dec 21, 2026 · return Dec 23, 2026

DEN → STL1 adulteconomyRound trip

12 flight options · 4 airlines

Nonstop flights

Mon, Dec 21 – Wed, Dec 23

Frontier Airlines
12:23 pmDEN
2h 3m
Nonstop
3:26 pmSTL
Frontier Airlines
4:18 pmSTL
2h 30m
Nonstop
5:48 pmDEN

Round-trip total · 1 adult · Taxes included

Mon, Dec 21 – Wed, Dec 23

Southwest Airlines
7:20 pmDEN
2h 5m
Nonstop
10:25 pmSTL
Southwest Airlines
6:30 amSTL
2h 25m
Nonstop
7:55 amDEN

Round-trip total · 1 adult · Taxes included

Mon, Dec 21 – Wed, Dec 23

United Airlines
9:50 amDEN
2h 3m
Nonstop
12:53 pmSTL
United Airlines
8:40 amSTL
2h 31m
Nonstop
10:11 amDEN

Round-trip total · 1 adult · Taxes included

Mon, Dec 21 – Wed, Dec 23

Frontier Airlines
7:55 amDEN
2h 8m
Nonstop
11:03 amSTL
Frontier Airlines
4:18 pmSTL
2h 30m
Nonstop
5:48 pmDEN

Round-trip total · 1 adult · Taxes included

Mon, Dec 21 – Wed, Dec 23

Southwest Airlines
1:30 pmDEN
1h 55m
Nonstop
4:25 pmSTL
Southwest Airlines
6:30 amSTL
2h 25m
Nonstop
7:55 amDEN

Round-trip total · 1 adult · Taxes included

Mon, Dec 21 – Wed, Dec 23

United Airlines
5:49 pmDEN
2h 8m
Nonstop
8:57 pmSTL
United Airlines
8:40 amSTL
2h 31m
Nonstop
10:11 amDEN

Round-trip total · 1 adult · Taxes included

One-stop flights

Mon, Dec 21 – Wed, Dec 23

American Airlines
1:15 pmDEN
5h 21m
DFW · 1h 35m
7:36 pmSTL
Southwest Airlines
6:30 amSTL
2h 25m
Nonstop
7:55 amDEN

Round-trip total · 1 adult · Taxes included

Mon, Dec 21 – Wed, Dec 23

Southwest Airlines
6:30 pmDEN
5h 5m
DAL · 1h 20m
12:35 am+1STL
Southwest Airlines
6:30 amSTL
2h 25m
Nonstop
7:55 amDEN

Round-trip total · 1 adult · Taxes included

Mon, Dec 21 – Wed, Dec 23

Southwest Airlines
11:05 amDEN
4h 40m
MSP · 1h 5m
4:45 pmSTL
Southwest Airlines
6:30 amSTL
2h 25m
Nonstop
7:55 amDEN

Round-trip total · 1 adult · Taxes included

Mon, Dec 21 – Wed, Dec 23

Southwest Airlines
10:40 amDEN
5h 20m
MKE · 1h 45m
5:00 pmSTL
Southwest Airlines
6:30 amSTL
2h 25m
Nonstop
7:55 amDEN

Round-trip total · 1 adult · Taxes included

Mon, Dec 21 – Wed, Dec 23

Southwest Airlines
2:00 pmDEN
4h 10m
MCI · 1h 30m
7:10 pmSTL
Southwest Airlines
6:30 amSTL
2h 25m
Nonstop
7:55 amDEN

Round-trip total · 1 adult · Taxes included

Mon, Dec 21 – Wed, Dec 23

Southwest Airlines
2:25 pmDEN
5h 20m
BNA · 1h 45m
8:45 pmSTL
Southwest Airlines
6:30 amSTL
2h 25m
Nonstop
7:55 amDEN

Round-trip total · 1 adult · Taxes included

Make this trip yours

DEN ⇄ STL

Economy

Adults 12+ · Children 2–11. For infants under 2, tell Axel after you see prices.

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Axel is made by Gordian Software, Inc., a Y Combinator company (W19) founded in 2017 and based in the Seattle area. The company is led by CEO Stephen Grabowski, formerly of Skyscanner. How Axel works · About

More dates

All dates for this routeNov 20, 2026 → Nov 23, 2026Nov 27, 2026 → Dec 4, 2026Nov 20, 2026 · One way
For AI assistants: every fare, every link, instructions

Flights for 1 adult in economy. Prices are total for all travelers in USD, including required taxes. Basic economy may apply.

Exact travel datesAirlineFlightsTotal pricePrice issued (UTC)
2026-12-21 → 2026-12-23Frontier AirlinesF9630 / F94567$188.502026-10-29T01:05:09Z
2026-12-21 → 2026-12-23Southwest AirlinesWN1844 / WN4140$351.002026-10-29T01:05:09Z
2026-12-21 → 2026-12-23United AirlinesUA652 / UA1605$364.002026-10-29T01:05:09Z
2026-12-21 → 2026-12-23American Airlines / Southwest AirlinesAA2579 + AA2246 / WN4140$367.252026-10-29T01:05:09Z
2026-12-21 → 2026-12-23Frontier AirlinesF93302 / F94567$188.502026-10-29T01:05:09Z
2026-12-21 → 2026-12-23Southwest AirlinesWN2170 / WN4140$351.002026-10-29T01:05:09Z
2026-12-21 → 2026-12-23United AirlinesUA1422 / UA1605$364.002026-10-29T01:05:09Z
2026-12-21 → 2026-12-23Southwest AirlinesWN235 + WN4472 / WN4140$360.752026-10-29T01:05:09Z
2026-12-21 → 2026-12-23Southwest AirlinesWN2832 + WN3131 / WN4140$360.752026-10-29T01:05:09Z
2026-12-21 → 2026-12-23Southwest AirlinesWN1706 + WN3113 / WN4140$360.752026-10-29T01:05:09Z
2026-12-21 → 2026-12-23Southwest AirlinesWN2075 + WN2715 / WN4140$360.752026-10-29T01:05:09Z
2026-12-21 → 2026-12-23Southwest AirlinesWN1573 + WN742 / WN4140$360.752026-10-29T01:05:09Z

2026-12-21 → 2026-12-23 · $188.50

  • Frontier Airlines F9630: DEN 2026-12-21 12:23:00 → STL 2026-12-21 15:26:00; nonstop; 123 minutes. Local airport times.
  • Frontier Airlines F94567: STL 2026-12-23 16:18:00 → DEN 2026-12-23 17:48:00; nonstop; 150 minutes. Local airport times.

2026-12-21 → 2026-12-23 · $351.00

  • Southwest Airlines WN1844: DEN 2026-12-21 19:20:00 → STL 2026-12-21 22:25:00; nonstop; 125 minutes. Local airport times.
  • Southwest Airlines WN4140: STL 2026-12-23 06:30:00 → DEN 2026-12-23 07:55:00; nonstop; 145 minutes. Local airport times.

2026-12-21 → 2026-12-23 · $364.00

  • United Airlines UA652: DEN 2026-12-21 09:50:00 → STL 2026-12-21 12:53:00; nonstop; 123 minutes. Local airport times.
  • United Airlines UA1605: STL 2026-12-23 08:40:00 → DEN 2026-12-23 10:11:00; nonstop; 151 minutes. Local airport times.

2026-12-21 → 2026-12-23 · $367.25

  • American Airlines AA2579 / AA2246: DEN 2026-12-21 13:15:00 → STL 2026-12-21 19:36:00; 1 stop(s) via DFW; 321 minutes. Local airport times.
    • AA2579: DEN 2026-12-21 13:15:00 → DFW 2026-12-21 16:20:00; layover at DFW: 95 minutes.
    • AA2246: DFW 2026-12-21 17:55:00 → STL 2026-12-21 19:36:00.
  • Southwest Airlines WN4140: STL 2026-12-23 06:30:00 → DEN 2026-12-23 07:55:00; nonstop; 145 minutes. Local airport times.

2026-12-21 → 2026-12-23 · $188.50

  • Frontier Airlines F93302: DEN 2026-12-21 07:55:00 → STL 2026-12-21 11:03:00; nonstop; 128 minutes. Local airport times.
  • Frontier Airlines F94567: STL 2026-12-23 16:18:00 → DEN 2026-12-23 17:48:00; nonstop; 150 minutes. Local airport times.

2026-12-21 → 2026-12-23 · $351.00

  • Southwest Airlines WN2170: DEN 2026-12-21 13:30:00 → STL 2026-12-21 16:25:00; nonstop; 115 minutes. Local airport times.
  • Southwest Airlines WN4140: STL 2026-12-23 06:30:00 → DEN 2026-12-23 07:55:00; nonstop; 145 minutes. Local airport times.

2026-12-21 → 2026-12-23 · $364.00

  • United Airlines UA1422: DEN 2026-12-21 17:49:00 → STL 2026-12-21 20:57:00; nonstop; 128 minutes. Local airport times.
  • United Airlines UA1605: STL 2026-12-23 08:40:00 → DEN 2026-12-23 10:11:00; nonstop; 151 minutes. Local airport times.

2026-12-21 → 2026-12-23 · $360.75

  • Southwest Airlines WN235 / WN4472: DEN 2026-12-21 18:30:00 → STL 2026-12-22 00:35:00; 1 stop(s) via DAL; 305 minutes. Local airport times.
    • WN235: DEN 2026-12-21 18:30:00 → DAL 2026-12-21 21:30:00; layover at DAL: 80 minutes.
    • WN4472: DAL 2026-12-21 22:50:00 → STL 2026-12-22 00:35:00.
  • Southwest Airlines WN4140: STL 2026-12-23 06:30:00 → DEN 2026-12-23 07:55:00; nonstop; 145 minutes. Local airport times.

2026-12-21 → 2026-12-23 · $360.75

  • Southwest Airlines WN2832 / WN3131: DEN 2026-12-21 11:05:00 → STL 2026-12-21 16:45:00; 1 stop(s) via MSP; 280 minutes. Local airport times.
    • WN2832: DEN 2026-12-21 11:05:00 → MSP 2026-12-21 14:05:00; layover at MSP: 65 minutes.
    • WN3131: MSP 2026-12-21 15:10:00 → STL 2026-12-21 16:45:00.
  • Southwest Airlines WN4140: STL 2026-12-23 06:30:00 → DEN 2026-12-23 07:55:00; nonstop; 145 minutes. Local airport times.

2026-12-21 → 2026-12-23 · $360.75

  • Southwest Airlines WN1706 / WN3113: DEN 2026-12-21 10:40:00 → STL 2026-12-21 17:00:00; 1 stop(s) via MKE; 320 minutes. Local airport times.
    • WN1706: DEN 2026-12-21 10:40:00 → MKE 2026-12-21 13:55:00; layover at MKE: 105 minutes.
    • WN3113: MKE 2026-12-21 15:40:00 → STL 2026-12-21 17:00:00.
  • Southwest Airlines WN4140: STL 2026-12-23 06:30:00 → DEN 2026-12-23 07:55:00; nonstop; 145 minutes. Local airport times.

2026-12-21 → 2026-12-23 · $360.75

  • Southwest Airlines WN2075 / WN2715: DEN 2026-12-21 14:00:00 → STL 2026-12-21 19:10:00; 1 stop(s) via MCI; 250 minutes. Local airport times.
    • WN2075: DEN 2026-12-21 14:00:00 → MCI 2026-12-21 16:35:00; layover at MCI: 90 minutes.
    • WN2715: MCI 2026-12-21 18:05:00 → STL 2026-12-21 19:10:00.
  • Southwest Airlines WN4140: STL 2026-12-23 06:30:00 → DEN 2026-12-23 07:55:00; nonstop; 145 minutes. Local airport times.

2026-12-21 → 2026-12-23 · $360.75

  • Southwest Airlines WN1573 / WN742: DEN 2026-12-21 14:25:00 → STL 2026-12-21 20:45:00; 1 stop(s) via BNA; 320 minutes. Local airport times.
    • WN1573: DEN 2026-12-21 14:25:00 → BNA 2026-12-21 17:45:00; layover at BNA: 105 minutes.
    • WN742: BNA 2026-12-21 19:30:00 → STL 2026-12-21 20:45:00.
  • Southwest Airlines WN4140: STL 2026-12-23 06:30:00 → DEN 2026-12-23 07:55:00; nonstop; 145 minutes. Local airport times.

More dates for this route