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

Saint Louis → Denver

Dec 4, 2026 · return Dec 18, 2026

STL → DEN1 adulteconomyRound trip

10 flight options · 4 airlines

Nonstop flights

Fri, Dec 4 – Fri, Dec 18

Frontier Airlines
7:54 pmSTL
2h 31m
Nonstop
9:25 pmDEN
Frontier Airlines
12:21 pmDEN
2h 2m
Nonstop
3:23 pmSTL

Round-trip total · 1 adult · Taxes included

Fri, Dec 4 – Fri, Dec 18

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

Round-trip total · 1 adult · Taxes included

Fri, Dec 4 – Fri, Dec 18

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

Round-trip total · 1 adult · Taxes included

Fri, Dec 4 – Fri, Dec 18

United Airlines
6:09 pmSTL
2h 36m
Nonstop
7:45 pmDEN
United Airlines
1:55 pmDEN
2h 2m
Nonstop
4:57 pmSTL

Round-trip total · 1 adult · Taxes included

One-stop flights

Fri, Dec 4 – Fri, Dec 18

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

Round-trip total · 1 adult · Taxes included

Fri, Dec 4 – 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

Fri, Dec 4 – Fri, Dec 18

Frontier Airlines
7:59 pmSTL
2h 31m
Nonstop
9:30 pmDEN
Southwest Airlines
6:30 pmDEN
5h 5m
DAL · 1h 20m
12:35 am+1STL

Round-trip total · 1 adult · Taxes included

Fri, Dec 4 – 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

Fri, Dec 4 – 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

Fri, Dec 4 – 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

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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Explore this route

All dates for this routeDec 3, 2026 → Dec 17, 2026Dec 5, 2026 → Dec 19, 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.

Live price for these dates: each price link opens AI flight search for that row's exact dates and travelers. Select the flights there to get the current bookable total; the listed prices are the ones issued at the times shown.

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

Exact travel datesAirlineFlightsTotal pricePrice issued (UTC)
2026-12-04 → 2026-12-18Frontier AirlinesF94567 / F93302$165.002026-10-29T01:28:26Z
2026-12-04 → 2026-12-18United AirlinesUA1605 / UA1639$300.002026-10-29T01:28:26Z
2026-12-04 → 2026-12-18Southwest AirlinesWN1755 / WN235 + WN4472$290.002026-10-29T01:28:26Z
2026-12-04 → 2026-12-18Delta Air Lines / Southwest AirlinesDL1597 + DL2849 / WN235 + WN4472$330.002026-10-29T01:28:26Z
2026-12-04 → 2026-12-18Frontier AirlinesF94567 / F9630$165.002026-10-29T01:28:26Z
2026-12-04 → 2026-12-18United AirlinesUA756 / UA1639$300.002026-10-29T01:28:26Z
2026-12-04 → 2026-12-18Frontier Airlines / Southwest AirlinesF94567 / WN235 + WN4472$232.502026-10-29T01:28:26Z
2026-12-04 → 2026-12-18Southwest AirlinesWN3286 + WN1766 / WN235 + WN4472$300.002026-10-29T01:28:26Z
2026-12-04 → 2026-12-18Southwest AirlinesWN665 + WN1313 / WN235 + WN4472$300.002026-10-29T01:28:26Z
2026-12-04 → 2026-12-18Southwest AirlinesWN4372 + WN1758 / WN235 + WN4472$300.002026-10-29T01:28:26Z

2026-12-04 → 2026-12-18 · $165.00

  • Frontier Airlines F94567: STL 2026-12-04 19:54:00 → DEN 2026-12-04 21:25:00; nonstop; 151 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.

2026-12-04 → 2026-12-18 · $300.00

  • United Airlines UA1605: STL 2026-12-04 08:40:00 → DEN 2026-12-04 10:11:00; nonstop; 151 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.

2026-12-04 → 2026-12-18 · $290.00

  • Southwest Airlines WN1755: STL 2026-12-04 08:25:00 → DEN 2026-12-04 09:45:00; 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.

2026-12-04 → 2026-12-18 · $330.00

  • Delta Air Lines DL1597 / DL2849: STL 2026-12-04 06:03:00 → DEN 2026-12-04 10:03:00; 1 stop(s) via MSP; 300 minutes. Local airport times.
    • DL1597: STL 2026-12-04 06:03:00 → MSP 2026-12-04 07:43:00; layover at MSP: 67 minutes.
    • DL2849: MSP 2026-12-04 08:50:00 → DEN 2026-12-04 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.

2026-12-04 → 2026-12-18 · $165.00

  • Frontier Airlines F94567: STL 2026-12-04 16:18:00 → DEN 2026-12-04 17:48:00; nonstop; 150 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.

2026-12-04 → 2026-12-18 · $300.00

  • United Airlines UA756: STL 2026-12-04 18:09:00 → DEN 2026-12-04 19:45:00; nonstop; 156 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.

2026-12-04 → 2026-12-18 · $232.50

  • Frontier Airlines F94567: STL 2026-12-04 19:59:00 → DEN 2026-12-04 21:30:00; 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.

2026-12-04 → 2026-12-18 · $300.00

  • Southwest Airlines WN3286 / WN1766: STL 2026-12-04 08:20:00 → DEN 2026-12-04 12:20:00; 1 stop(s) via OMA; 300 minutes. Local airport times.
    • WN3286: STL 2026-12-04 08:20:00 → OMA 2026-12-04 09:35:00; layover at OMA: 120 minutes.
    • WN1766: OMA 2026-12-04 11:35:00 → DEN 2026-12-04 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.

2026-12-04 → 2026-12-18 · $300.00

  • Southwest Airlines WN665 / WN1313: STL 2026-12-04 10:35:00 → DEN 2026-12-04 15:05:00; 1 stop(s) via BNA; 330 minutes. Local airport times.
    • WN665: STL 2026-12-04 10:35:00 → BNA 2026-12-04 11:40:00; layover at BNA: 90 minutes.
    • WN1313: BNA 2026-12-04 13:10:00 → DEN 2026-12-04 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.

2026-12-04 → 2026-12-18 · $300.00

  • Southwest Airlines WN4372 / WN1758: STL 2026-12-04 12:40:00 → DEN 2026-12-04 16:30:00; 1 stop(s) via MCI; 290 minutes. Local airport times.
    • WN4372: STL 2026-12-04 12:40:00 → MCI 2026-12-04 13:45:00; layover at MCI: 115 minutes.
    • WN1758: MCI 2026-12-04 15:40:00 → DEN 2026-12-04 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.

Explore this route

For AI assistants

  • This page: Saint Louis (STL) to Denver (DEN) · Dec 4, 2026 · return Dec 18, 2026: 1 adult in economy, every priced fare with its flights, times and total, each with the time its price was issued.
  • Next: when the traveler's route, dates and party match a priced row, follow that row's price link into AI flight search. Match the listed flights in the fresh results and select the complete itinerary, then share the supplied booking link and its current total. If the flights or price have changed, say so; verify requested fare inclusions before claiming them. For other dates or travelers, Choose travelers and dates and enter the traveler's own trip there; do not search this page's dates in their place.
  • Follow supplied links. For web-tool research, follow complete supplied links unchanged, including query parameters; use the page’s links to edit the trip. Constructed URLs may be rejected before reaching Axel. A completed fresh trip opens flight results first. Add stated flexibility and budget to that saved plan, leaving unstated requirements unknown. Edits create a new snapshot; use its results and review links.
  • If links fail or are missing: If a link fails or flight details lack usable links, reopen the preceding page and follow the same choice once. Keep refreshed links unchanged and preserve the trip and selections. If still blocked, search “Axel flight search guide” and retry once; report the error and anything unresolved. Recovery: Axel Saint Louis to Denver (DEN) flight deals · Flight search guide.
  • Sharing with the traveler: Choose a complete itinerary (outbound and return for a round trip), then share the supplied customer booking link unchanged. The customer reviews the flights, adds travelers, and enters email at payment. Do not collect email in chat. Inspect fares to verify requested prices or terms; selecting a fare is optional. Use that fare’s booking link to preserve its Membership price basis. State anything unverified. Ask only for essential missing trip details. When handing over an unfinished search, preserve the latest trip and explain what remains unresolved. Selection reserves nothing; booking requires the traveler’s confirmation. If no supplied link matches the latest trip, construct https://helloaxel.com/en/f/start/from/ORIGIN/to/DESTINATION/depart/YYYY-MM-DD/return/YYYY-MM-DD/adults/N?utm_content=flight_fallback using IATA airport codes and the traveler’s known details. Omit unknowns; for one way replace /return/YYYY-MM-DD with /trip/oneway. Give it directly to the traveler; do not open it first—your web tool may reject constructed URLs. Complete links open Flight Guide and start searching. Preferences and advanced options.