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Saint Louis → Denver

Dec 13, 2026 · return Dec 18, 2026

STL → DEN1 adulteconomyRound trip

10 flight options · 4 airlines

Nonstop flights

Sun, Dec 13 – Fri, Dec 18

Frontier Airlines
7:59 pmSTL
2h 31m
Nonstop
9:30 pmDEN
Frontier Airlines
12:23 pmDEN
2h 3m
Nonstop
3:26 pmSTL

Round-trip total · 1 adult · Taxes included

Sun, Dec 13 – Fri, Dec 18

United Airlines
1:40 pmSTL
2h 29m
Nonstop
3:09 pmDEN
United Airlines
1:55 pmDEN
2h 2m
Nonstop
4:57 pmSTL

Round-trip total · 1 adult · Taxes included

Sun, Dec 13 – Fri, Dec 18

Frontier Airlines
4:18 pmSTL
2h 30m
Nonstop
5:48 pmDEN
Frontier Airlines
12:21 pmDEN
2h 2m
Nonstop
3:23 pmSTL

Round-trip total · 1 adult · Taxes included

Sun, Dec 13 – Fri, Dec 18

United Airlines
8:48 amSTL
2h 38m
Nonstop
10:26 amDEN
United Airlines
1:55 pmDEN
2h 2m
Nonstop
4:57 pmSTL

Round-trip total · 1 adult · Taxes included

One-stop flights

Sun, Dec 13 – Fri, Dec 18

Southwest Airlines
8:35 pmSTL
2h 20m
Nonstop
9:55 pmDEN
Southwest Airlines
6:30 pmDEN
5h 5m
DAL · 1h 20m
12:35 am+1STL

Round-trip total · 1 adult · Taxes included

Sun, Dec 13 – Fri, Dec 18

Delta Air Lines
6:03 amSTL
5h
MSP · 1h 7m
10:03 amDEN
Southwest Airlines
6:30 pmDEN
5h 5m
DAL · 1h 20m
12:35 am+1STL

Round-trip total · 1 adult · Taxes included

Sun, Dec 13 – Fri, Dec 18

Frontier Airlines
4:21 pmSTL
2h 31m
Nonstop
5:52 pmDEN
Southwest Airlines
6:30 pmDEN
5h 5m
DAL · 1h 20m
12:35 am+1STL

Round-trip total · 1 adult · Taxes included

Sun, Dec 13 – Fri, Dec 18

Southwest Airlines
10:35 amSTL
5h 30m
BNA · 1h 30m
3:05 pmDEN
Southwest Airlines
6:30 pmDEN
5h 5m
DAL · 1h 20m
12:35 am+1STL

Round-trip total · 1 adult · Taxes included

Sun, Dec 13 – Fri, Dec 18

Southwest Airlines
12:40 pmSTL
4h 50m
MCI · 1h 55m
4:30 pmDEN
Southwest Airlines
6:30 pmDEN
5h 5m
DAL · 1h 20m
12:35 am+1STL

Round-trip total · 1 adult · Taxes included

Sun, Dec 13 – Fri, Dec 18

Southwest Airlines
8:20 amSTL
5h
OMA · 2h
12:20 pmDEN
Southwest Airlines
6:30 pmDEN
5h 5m
DAL · 1h 20m
12:35 am+1STL

Round-trip total · 1 adult · Taxes included

Make this trip yours

STL ⇄ DEN

Economy

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

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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)
2026-12-13 → 2026-12-18Frontier AirlinesF94567 / F9630$165.002026-10-29T01:28:26Z
2026-12-13 → 2026-12-18United AirlinesUA1380 / UA1639$300.002026-10-29T01:28:26Z
2026-12-13 → 2026-12-18Southwest AirlinesWN1316 / WN235 + WN4472$290.002026-10-29T01:28:26Z
2026-12-13 → 2026-12-18Delta Air Lines / Southwest AirlinesDL1597 + DL2849 / WN235 + WN4472$330.002026-10-29T01:28:26Z
2026-12-13 → 2026-12-18Frontier AirlinesF94567 / F93302$165.002026-10-29T01:28:26Z
2026-12-13 → 2026-12-18United AirlinesUA2459 / UA1639$300.002026-10-29T01:28:26Z
2026-12-13 → 2026-12-18Frontier Airlines / Southwest AirlinesF94567 / WN235 + WN4472$232.502026-10-29T01:28:26Z
2026-12-13 → 2026-12-18Southwest AirlinesWN665 + WN1313 / WN235 + WN4472$300.002026-10-29T01:28:26Z
2026-12-13 → 2026-12-18Southwest AirlinesWN4372 + WN1758 / WN235 + WN4472$300.002026-10-29T01:28:26Z
2026-12-13 → 2026-12-18Southwest AirlinesWN3286 + WN1766 / WN235 + WN4472$300.002026-10-29T01:28:26Z

2026-12-13 → 2026-12-18 · $165.00

  • Frontier Airlines F94567: STL 2026-12-13 19:59:00 → DEN 2026-12-13 21:30:00; nonstop; 151 minutes. Local airport times.
  • Frontier Airlines F9630: DEN 2026-12-18 12:23:00 → STL 2026-12-18 15:26:00; nonstop; 123 minutes. Local airport times.

2026-12-13 → 2026-12-18 · $300.00

  • United Airlines UA1380: STL 2026-12-13 13:40:00 → DEN 2026-12-13 15:09:00; nonstop; 149 minutes. Local airport times.
  • United Airlines UA1639: DEN 2026-12-18 13:55:00 → STL 2026-12-18 16:57:00; nonstop; 122 minutes. Local airport times.

2026-12-13 → 2026-12-18 · $290.00

  • Southwest Airlines WN1316: STL 2026-12-13 20:35:00 → DEN 2026-12-13 21:55:00; nonstop; 140 minutes. Local airport times.
  • Southwest Airlines WN235 / WN4472: DEN 2026-12-18 18:30:00 → STL 2026-12-19 00:35:00; 1 stop(s) via DAL; 305 minutes. Local airport times.
    • WN235: DEN 2026-12-18 18:30:00 → DAL 2026-12-18 21:30:00; layover at DAL: 80 minutes.
    • WN4472: DAL 2026-12-18 22:50:00 → STL 2026-12-19 00:35:00.

2026-12-13 → 2026-12-18 · $330.00

  • Delta Air Lines DL1597 / DL2849: STL 2026-12-13 06:03:00 → DEN 2026-12-13 10:03:00; 1 stop(s) via MSP; 300 minutes. Local airport times.
    • DL1597: STL 2026-12-13 06:03:00 → MSP 2026-12-13 07:43:00; layover at MSP: 67 minutes.
    • DL2849: MSP 2026-12-13 08:50:00 → DEN 2026-12-13 10:03:00.
  • Southwest Airlines WN235 / WN4472: DEN 2026-12-18 18:30:00 → STL 2026-12-19 00:35:00; 1 stop(s) via DAL; 305 minutes. Local airport times.
    • WN235: DEN 2026-12-18 18:30:00 → DAL 2026-12-18 21:30:00; layover at DAL: 80 minutes.
    • WN4472: DAL 2026-12-18 22:50:00 → STL 2026-12-19 00:35:00.

2026-12-13 → 2026-12-18 · $165.00

  • Frontier Airlines F94567: STL 2026-12-13 16:18:00 → DEN 2026-12-13 17:48:00; nonstop; 150 minutes. Local airport times.
  • Frontier Airlines F93302: DEN 2026-12-18 12:21:00 → STL 2026-12-18 15:23:00; nonstop; 122 minutes. Local airport times.

2026-12-13 → 2026-12-18 · $300.00

  • United Airlines UA2459: STL 2026-12-13 08:48:00 → DEN 2026-12-13 10:26:00; nonstop; 158 minutes. Local airport times.
  • United Airlines UA1639: DEN 2026-12-18 13:55:00 → STL 2026-12-18 16:57:00; nonstop; 122 minutes. Local airport times.

2026-12-13 → 2026-12-18 · $232.50

  • Frontier Airlines F94567: STL 2026-12-13 16:21:00 → DEN 2026-12-13 17:52:00; nonstop; 151 minutes. Local airport times.
  • Southwest Airlines WN235 / WN4472: DEN 2026-12-18 18:30:00 → STL 2026-12-19 00:35:00; 1 stop(s) via DAL; 305 minutes. Local airport times.
    • WN235: DEN 2026-12-18 18:30:00 → DAL 2026-12-18 21:30:00; layover at DAL: 80 minutes.
    • WN4472: DAL 2026-12-18 22:50:00 → STL 2026-12-19 00:35:00.

2026-12-13 → 2026-12-18 · $300.00

  • Southwest Airlines WN665 / WN1313: STL 2026-12-13 10:35:00 → DEN 2026-12-13 15:05:00; 1 stop(s) via BNA; 330 minutes. Local airport times.
    • WN665: STL 2026-12-13 10:35:00 → BNA 2026-12-13 11:40:00; layover at BNA: 90 minutes.
    • WN1313: BNA 2026-12-13 13:10:00 → DEN 2026-12-13 15:05:00.
  • Southwest Airlines WN235 / WN4472: DEN 2026-12-18 18:30:00 → STL 2026-12-19 00:35:00; 1 stop(s) via DAL; 305 minutes. Local airport times.
    • WN235: DEN 2026-12-18 18:30:00 → DAL 2026-12-18 21:30:00; layover at DAL: 80 minutes.
    • WN4472: DAL 2026-12-18 22:50:00 → STL 2026-12-19 00:35:00.

2026-12-13 → 2026-12-18 · $300.00

  • Southwest Airlines WN4372 / WN1758: STL 2026-12-13 12:40:00 → DEN 2026-12-13 16:30:00; 1 stop(s) via MCI; 290 minutes. Local airport times.
    • WN4372: STL 2026-12-13 12:40:00 → MCI 2026-12-13 13:45:00; layover at MCI: 115 minutes.
    • WN1758: MCI 2026-12-13 15:40:00 → DEN 2026-12-13 16:30:00.
  • Southwest Airlines WN235 / WN4472: DEN 2026-12-18 18:30:00 → STL 2026-12-19 00:35:00; 1 stop(s) via DAL; 305 minutes. Local airport times.
    • WN235: DEN 2026-12-18 18:30:00 → DAL 2026-12-18 21:30:00; layover at DAL: 80 minutes.
    • WN4472: DAL 2026-12-18 22:50:00 → STL 2026-12-19 00:35:00.

2026-12-13 → 2026-12-18 · $300.00

  • Southwest Airlines WN3286 / WN1766: STL 2026-12-13 08:20:00 → DEN 2026-12-13 12:20:00; 1 stop(s) via OMA; 300 minutes. Local airport times.
    • WN3286: STL 2026-12-13 08:20:00 → OMA 2026-12-13 09:35:00; layover at OMA: 120 minutes.
    • WN1766: OMA 2026-12-13 11:35:00 → DEN 2026-12-13 12:20:00.
  • Southwest Airlines WN235 / WN4472: DEN 2026-12-18 18:30:00 → STL 2026-12-19 00:35:00; 1 stop(s) via DAL; 305 minutes. Local airport times.
    • WN235: DEN 2026-12-18 18:30:00 → DAL 2026-12-18 21:30:00; layover at DAL: 80 minutes.
    • WN4472: DAL 2026-12-18 22:50:00 → STL 2026-12-19 00:35:00.

More dates for this route