Travel with Axel,
get the best price.

Route overview: Denver to Saint Louis (STL) flight deals

Denver → Saint Louis

Dec 26, 2026 · return Dec 28, 2026

DEN → STL1 adulteconomyRound trip

12 flight options · 4 airlines

Nonstop flights

Sat, Dec 26 – Mon, Dec 28

Frontier Airlines
7:55 amDEN
2h 8m
Nonstop
11:03 amSTL
Frontier Airlines
7:54 pmSTL
2h 31m
Nonstop
9:25 pmDEN

Round-trip total · 1 adult · Taxes included

Sat, Dec 26 – Mon, Dec 28

Southwest Airlines
9:55 pmDEN
2h
Nonstop
12:55 am+1STL
Southwest Airlines
8:20 amSTL
2h 25m
Nonstop
9:45 amDEN

Round-trip total · 1 adult · Taxes included

Sat, Dec 26 – Mon, Dec 28

United Airlines
9:35 amDEN
2h 3m
Nonstop
12:38 pmSTL
United Airlines
8:40 amSTL
2h 31m
Nonstop
10:11 amDEN

Round-trip total · 1 adult · Taxes included

Sat, Dec 26 – Mon, Dec 28

Frontier Airlines
12:23 pmDEN
2h 3m
Nonstop
3:26 pmSTL
Frontier Airlines
7:54 pmSTL
2h 31m
Nonstop
9:25 pmDEN

Round-trip total · 1 adult · Taxes included

Sat, Dec 26 – Mon, Dec 28

Southwest Airlines
10:30 amDEN
2h
Nonstop
1:30 pmSTL
Southwest Airlines
8:20 amSTL
2h 25m
Nonstop
9:45 amDEN

Round-trip total · 1 adult · Taxes included

Sat, Dec 26 – Mon, Dec 28

United Airlines
1:55 pmDEN
2h 2m
Nonstop
4:57 pmSTL
United Airlines
8:40 amSTL
2h 31m
Nonstop
10:11 amDEN

Round-trip total · 1 adult · Taxes included

One-stop flights

Sat, Dec 26 – Mon, Dec 28

American Airlines
1:15 pmDEN
5h 21m
DFW · 1h 35m
7:36 pmSTL
Southwest Airlines
8:20 amSTL
2h 25m
Nonstop
9:45 amDEN

Round-trip total · 1 adult · Taxes included

Sat, Dec 26 – Mon, Dec 28

Southwest Airlines
9:50 pmDEN
2h
Nonstop
12:50 am+1STL
Southwest Airlines
10:35 amSTL
5h 30m
BNA · 1h 30m
3:05 pmDEN

Round-trip total · 1 adult · Taxes included

Sat, Dec 26 – Mon, Dec 28

Southwest Airlines
6:30 pmDEN
5h 5m
DAL · 1h 20m
12:35 am+1STL
Southwest Airlines
8:20 amSTL
2h 25m
Nonstop
9:45 amDEN

Round-trip total · 1 adult · Taxes included

Sat, Dec 26 – Mon, Dec 28

Southwest Airlines
10:40 amDEN
5h 20m
MKE · 1h 45m
5:00 pmSTL
Southwest Airlines
8:20 amSTL
2h 25m
Nonstop
9:45 amDEN

Round-trip total · 1 adult · Taxes included

Sat, Dec 26 – Mon, Dec 28

Southwest Airlines
2:00 pmDEN
4h 10m
MCI · 1h 30m
7:10 pmSTL
Southwest Airlines
8:20 amSTL
2h 25m
Nonstop
9:45 amDEN

Round-trip total · 1 adult · Taxes included

Sat, Dec 26 – Mon, Dec 28

Southwest Airlines
11:05 amDEN
4h 40m
MSP · 1h 5m
4:45 pmSTL
Southwest Airlines
8:20 amSTL
2h 25m
Nonstop
9:45 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.

No account needed to see prices.

Already have an account? Log in

Why book with Axel
  • A real airline bookingThe booking is in the airline’s own system under your name. After you book, Frontier Airlines emails you its confirmation code and e-ticket, usually within 15 minutes and occasionally up to a couple of hours while the booking is processed.
  • Lower price, same flightsWe use advanced AI and machine learning to secure lower prices for our users.
  • Not satisfied? Full refund.If you are unhappy with the experience for any reason, or simply change your mind, cancel within 24 hours of booking (departure 7+ days away) and we refund you in full. We stand by our product. Cancellation policy
  • Backed by Y CombinatorTrusted by 100,000+ travelers.

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

Explore this route

All dates for this routeDec 25, 2026 → Dec 27, 2026Dec 27, 2026 → Dec 29, 2026
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.

Route overview: Denver to Saint Louis (STL) flight deals

Exact travel datesAirlineFlightsTotal pricePrice issued (UTC)
2026-12-26 → 2026-12-28Frontier AirlinesF93302 / F94567$184.882026-10-29T01:05:09Z
2026-12-26 → 2026-12-28Southwest AirlinesWN1845 / WN4141$344.252026-10-29T01:05:09Z
2026-12-26 → 2026-12-28United AirlinesUA652 / UA1605$357.002026-10-29T01:05:09Z
2026-12-26 → 2026-12-28American Airlines / Southwest AirlinesAA2579 + AA2246 / WN4141$360.502026-10-29T01:05:09Z
2026-12-26 → 2026-12-28Frontier AirlinesF9630 / F94567$184.882026-10-29T01:05:09Z
2026-12-26 → 2026-12-28Southwest AirlinesWN719 / WN4141$344.252026-10-29T01:05:09Z
2026-12-26 → 2026-12-28United AirlinesUA1639 / UA1605$357.002026-10-29T01:05:09Z
2026-12-26 → 2026-12-28Southwest AirlinesWN1845 / WN665 + WN1313$353.632026-10-29T01:05:09Z
2026-12-26 → 2026-12-28Southwest AirlinesWN235 + WN4472 / WN4141$354.002026-10-29T01:05:09Z
2026-12-26 → 2026-12-28Southwest AirlinesWN1706 + WN3113 / WN4141$354.002026-10-29T01:05:09Z
2026-12-26 → 2026-12-28Southwest AirlinesWN2075 + WN2715 / WN4141$354.002026-10-29T01:05:09Z
2026-12-26 → 2026-12-28Southwest AirlinesWN2832 + WN3131 / WN4141$354.002026-10-29T01:05:09Z

2026-12-26 → 2026-12-28 · $184.88

  • Frontier Airlines F93302: DEN 2026-12-26 07:55:00 → STL 2026-12-26 11:03:00; nonstop; 128 minutes. Local airport times.
  • Frontier Airlines F94567: STL 2026-12-28 19:54:00 → DEN 2026-12-28 21:25:00; nonstop; 151 minutes. Local airport times.

2026-12-26 → 2026-12-28 · $344.25

  • Southwest Airlines WN1845: DEN 2026-12-26 21:55:00 → STL 2026-12-27 00:55:00; nonstop; 120 minutes. Local airport times.
  • Southwest Airlines WN4141: STL 2026-12-28 08:20:00 → DEN 2026-12-28 09:45:00; nonstop; 145 minutes. Local airport times.

2026-12-26 → 2026-12-28 · $357.00

  • United Airlines UA652: DEN 2026-12-26 09:35:00 → STL 2026-12-26 12:38:00; nonstop; 123 minutes. Local airport times.
  • United Airlines UA1605: STL 2026-12-28 08:40:00 → DEN 2026-12-28 10:11:00; nonstop; 151 minutes. Local airport times.

2026-12-26 → 2026-12-28 · $360.50

  • American Airlines AA2579 / AA2246: DEN 2026-12-26 13:15:00 → STL 2026-12-26 19:36:00; 1 stop(s) via DFW; 321 minutes. Local airport times.
    • AA2579: DEN 2026-12-26 13:15:00 → DFW 2026-12-26 16:20:00; layover at DFW: 95 minutes.
    • AA2246: DFW 2026-12-26 17:55:00 → STL 2026-12-26 19:36:00.
  • Southwest Airlines WN4141: STL 2026-12-28 08:20:00 → DEN 2026-12-28 09:45:00; nonstop; 145 minutes. Local airport times.

2026-12-26 → 2026-12-28 · $184.88

  • Frontier Airlines F9630: DEN 2026-12-26 12:23:00 → STL 2026-12-26 15:26:00; nonstop; 123 minutes. Local airport times.
  • Frontier Airlines F94567: STL 2026-12-28 19:54:00 → DEN 2026-12-28 21:25:00; nonstop; 151 minutes. Local airport times.

2026-12-26 → 2026-12-28 · $344.25

  • Southwest Airlines WN719: DEN 2026-12-26 10:30:00 → STL 2026-12-26 13:30:00; nonstop; 120 minutes. Local airport times.
  • Southwest Airlines WN4141: STL 2026-12-28 08:20:00 → DEN 2026-12-28 09:45:00; nonstop; 145 minutes. Local airport times.

2026-12-26 → 2026-12-28 · $357.00

  • United Airlines UA1639: DEN 2026-12-26 13:55:00 → STL 2026-12-26 16:57:00; nonstop; 122 minutes. Local airport times.
  • United Airlines UA1605: STL 2026-12-28 08:40:00 → DEN 2026-12-28 10:11:00; nonstop; 151 minutes. Local airport times.

2026-12-26 → 2026-12-28 · $353.63

  • Southwest Airlines WN1845: DEN 2026-12-26 21:50:00 → STL 2026-12-27 00:50:00; nonstop; 120 minutes. Local airport times.
  • Southwest Airlines WN665 / WN1313: STL 2026-12-28 10:35:00 → DEN 2026-12-28 15:05:00; 1 stop(s) via BNA; 330 minutes. Local airport times.
    • WN665: STL 2026-12-28 10:35:00 → BNA 2026-12-28 11:40:00; layover at BNA: 90 minutes.
    • WN1313: BNA 2026-12-28 13:10:00 → DEN 2026-12-28 15:05:00.

2026-12-26 → 2026-12-28 · $354.00

  • Southwest Airlines WN235 / WN4472: DEN 2026-12-26 18:30:00 → STL 2026-12-27 00:35:00; 1 stop(s) via DAL; 305 minutes. Local airport times.
    • WN235: DEN 2026-12-26 18:30:00 → DAL 2026-12-26 21:30:00; layover at DAL: 80 minutes.
    • WN4472: DAL 2026-12-26 22:50:00 → STL 2026-12-27 00:35:00.
  • Southwest Airlines WN4141: STL 2026-12-28 08:20:00 → DEN 2026-12-28 09:45:00; nonstop; 145 minutes. Local airport times.

2026-12-26 → 2026-12-28 · $354.00

  • Southwest Airlines WN1706 / WN3113: DEN 2026-12-26 10:40:00 → STL 2026-12-26 17:00:00; 1 stop(s) via MKE; 320 minutes. Local airport times.
    • WN1706: DEN 2026-12-26 10:40:00 → MKE 2026-12-26 13:55:00; layover at MKE: 105 minutes.
    • WN3113: MKE 2026-12-26 15:40:00 → STL 2026-12-26 17:00:00.
  • Southwest Airlines WN4141: STL 2026-12-28 08:20:00 → DEN 2026-12-28 09:45:00; nonstop; 145 minutes. Local airport times.

2026-12-26 → 2026-12-28 · $354.00

  • Southwest Airlines WN2075 / WN2715: DEN 2026-12-26 14:00:00 → STL 2026-12-26 19:10:00; 1 stop(s) via MCI; 250 minutes. Local airport times.
    • WN2075: DEN 2026-12-26 14:00:00 → MCI 2026-12-26 16:35:00; layover at MCI: 90 minutes.
    • WN2715: MCI 2026-12-26 18:05:00 → STL 2026-12-26 19:10:00.
  • Southwest Airlines WN4141: STL 2026-12-28 08:20:00 → DEN 2026-12-28 09:45:00; nonstop; 145 minutes. Local airport times.

2026-12-26 → 2026-12-28 · $354.00

  • Southwest Airlines WN2832 / WN3131: DEN 2026-12-26 11:05:00 → STL 2026-12-26 16:45:00; 1 stop(s) via MSP; 280 minutes. Local airport times.
    • WN2832: DEN 2026-12-26 11:05:00 → MSP 2026-12-26 14:05:00; layover at MSP: 65 minutes.
    • WN3131: MSP 2026-12-26 15:10:00 → STL 2026-12-26 16:45:00.
  • Southwest Airlines WN4141: STL 2026-12-28 08:20:00 → DEN 2026-12-28 09:45:00; nonstop; 145 minutes. Local airport times.

Explore this route