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

Saint Louis → Denver

Dec 9, 2026 · return Dec 15, 2026

STL → DEN1 adulteconomyRound trip

12 flight options · 4 airlines

Nonstop flights

Wed, Dec 9 – Tue, Dec 15

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

Wed, Dec 9 – Tue, Dec 15

Southwest Airlines
6:30 amSTL
2h 25m
Nonstop
7:55 amDEN
Southwest Airlines
3:40 pmDEN
1h 55m
Nonstop
6:35 pmSTL

Round-trip total · 1 adult · Taxes included

Wed, Dec 9 – Tue, Dec 15

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

Wed, Dec 9 – Tue, Dec 15

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

Wed, Dec 9 – Tue, Dec 15

Southwest Airlines
5:25 pmSTL
2h 30m
Nonstop
6:55 pmDEN
Southwest Airlines
3:40 pmDEN
1h 55m
Nonstop
6:35 pmSTL

Round-trip total · 1 adult · Taxes included

Wed, Dec 9 – Tue, Dec 15

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

One-stop flights

Wed, Dec 9 – Tue, Dec 15

Delta Air Lines
6:03 amSTL
5h
MSP · 1h 7m
10:03 amDEN
Southwest Airlines
3:40 pmDEN
1h 55m
Nonstop
6:35 pmSTL

Round-trip total · 1 adult · Taxes included

Wed, Dec 9 – Tue, Dec 15

Southwest Airlines
3:50 pmSTL
6h 5m
DAL · 2h 10m
8:55 pmDEN
Southwest Airlines
3:40 pmDEN
1h 55m
Nonstop
6:35 pmSTL

Round-trip total · 1 adult · Taxes included

Wed, Dec 9 – Tue, Dec 15

Southwest Airlines
10:35 amSTL
5h 30m
BNA · 1h 30m
3:05 pmDEN
Southwest Airlines
3:40 pmDEN
1h 55m
Nonstop
6:35 pmSTL

Round-trip total · 1 adult · Taxes included

Wed, Dec 9 – Tue, Dec 15

Southwest Airlines
12:40 pmSTL
4h 50m
MCI · 1h 55m
4:30 pmDEN
Southwest Airlines
3:40 pmDEN
1h 55m
Nonstop
6:35 pmSTL

Round-trip total · 1 adult · Taxes included

Wed, Dec 9 – Tue, Dec 15

Southwest Airlines
8:20 amSTL
5h
OMA · 2h
12:20 pmDEN
Southwest Airlines
3:40 pmDEN
1h 55m
Nonstop
6:35 pmSTL

Round-trip total · 1 adult · Taxes included

Wed, Dec 9 – Tue, Dec 15

United Airlines
5:25 amSTL
6h 1m
ORD · 1h 42m
10:26 amDEN
United Airlines
1:55 pmDEN
2h 2m
Nonstop
4:57 pmSTL

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 8, 2026 → Dec 14, 2026Dec 10, 2026 → Dec 16, 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)
2026-12-09 → 2026-12-15Frontier AirlinesF94567 / F9630$165.002026-10-29T01:28:26Z
2026-12-09 → 2026-12-15Southwest AirlinesWN4140 / WN2170$280.002026-10-29T01:28:26Z
2026-12-09 → 2026-12-15United AirlinesUA1380 / UA1639$300.002026-10-29T01:28:26Z
2026-12-09 → 2026-12-15Delta Air Lines / Southwest AirlinesDL1597 + DL2849 / WN2170$320.002026-10-29T01:28:26Z
2026-12-09 → 2026-12-15Frontier AirlinesF94567 / F93302$165.002026-10-29T01:28:26Z
2026-12-09 → 2026-12-15Southwest AirlinesWN4144 / WN2170$280.002026-10-29T01:28:26Z
2026-12-09 → 2026-12-15United AirlinesUA1605 / UA1639$300.002026-10-29T01:28:26Z
2026-12-09 → 2026-12-15Southwest AirlinesWN2015 + WN200 / WN2170$290.002026-10-29T01:28:26Z
2026-12-09 → 2026-12-15Southwest AirlinesWN665 + WN1313 / WN2170$290.002026-10-29T01:28:26Z
2026-12-09 → 2026-12-15Southwest AirlinesWN4372 + WN1758 / WN2170$290.002026-10-29T01:28:26Z
2026-12-09 → 2026-12-15Southwest AirlinesWN3286 + WN1766 / WN2170$290.002026-10-29T01:28:26Z
2026-12-09 → 2026-12-15United AirlinesUA4439 + UA2495 / UA1639$310.002026-10-29T01:28:26Z

2026-12-09 → 2026-12-15 · $165.00

  • Frontier Airlines F94567: STL 2026-12-09 19:59:00 → DEN 2026-12-09 21:30:00; nonstop; 151 minutes. Local airport times.
  • Frontier Airlines F9630: DEN 2026-12-15 12:23:00 → STL 2026-12-15 15:26:00; nonstop; 123 minutes. Local airport times.

2026-12-09 → 2026-12-15 · $280.00

  • Southwest Airlines WN4140: STL 2026-12-09 06:30:00 → DEN 2026-12-09 07:55:00; nonstop; 145 minutes. Local airport times.
  • Southwest Airlines WN2170: DEN 2026-12-15 15:40:00 → STL 2026-12-15 18:35:00; nonstop; 115 minutes. Local airport times.

2026-12-09 → 2026-12-15 · $300.00

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

2026-12-09 → 2026-12-15 · $320.00

  • Delta Air Lines DL1597 / DL2849: STL 2026-12-09 06:03:00 → DEN 2026-12-09 10:03:00; 1 stop(s) via MSP; 300 minutes. Local airport times.
    • DL1597: STL 2026-12-09 06:03:00 → MSP 2026-12-09 07:43:00; layover at MSP: 67 minutes.
    • DL2849: MSP 2026-12-09 08:50:00 → DEN 2026-12-09 10:03:00.
  • Southwest Airlines WN2170: DEN 2026-12-15 15:40:00 → STL 2026-12-15 18:35:00; nonstop; 115 minutes. Local airport times.

2026-12-09 → 2026-12-15 · $165.00

  • Frontier Airlines F94567: STL 2026-12-09 16:18:00 → DEN 2026-12-09 17:48:00; nonstop; 150 minutes. Local airport times.
  • Frontier Airlines F93302: DEN 2026-12-15 12:21:00 → STL 2026-12-15 15:23:00; nonstop; 122 minutes. Local airport times.

2026-12-09 → 2026-12-15 · $280.00

  • Southwest Airlines WN4144: STL 2026-12-09 17:25:00 → DEN 2026-12-09 18:55:00; nonstop; 150 minutes. Local airport times.
  • Southwest Airlines WN2170: DEN 2026-12-15 15:40:00 → STL 2026-12-15 18:35:00; nonstop; 115 minutes. Local airport times.

2026-12-09 → 2026-12-15 · $300.00

  • United Airlines UA1605: STL 2026-12-09 08:40:00 → DEN 2026-12-09 10:11:00; nonstop; 151 minutes. Local airport times.
  • United Airlines UA1639: DEN 2026-12-15 13:55:00 → STL 2026-12-15 16:57:00; nonstop; 122 minutes. Local airport times.

2026-12-09 → 2026-12-15 · $290.00

  • Southwest Airlines WN2015 / WN200: STL 2026-12-09 15:50:00 → DEN 2026-12-09 20:55:00; 1 stop(s) via DAL; 365 minutes. Local airport times.
    • WN2015: STL 2026-12-09 15:50:00 → DAL 2026-12-09 17:30:00; layover at DAL: 130 minutes.
    • WN200: DAL 2026-12-09 19:40:00 → DEN 2026-12-09 20:55:00.
  • Southwest Airlines WN2170: DEN 2026-12-15 15:40:00 → STL 2026-12-15 18:35:00; nonstop; 115 minutes. Local airport times.

2026-12-09 → 2026-12-15 · $290.00

  • Southwest Airlines WN665 / WN1313: STL 2026-12-09 10:35:00 → DEN 2026-12-09 15:05:00; 1 stop(s) via BNA; 330 minutes. Local airport times.
    • WN665: STL 2026-12-09 10:35:00 → BNA 2026-12-09 11:40:00; layover at BNA: 90 minutes.
    • WN1313: BNA 2026-12-09 13:10:00 → DEN 2026-12-09 15:05:00.
  • Southwest Airlines WN2170: DEN 2026-12-15 15:40:00 → STL 2026-12-15 18:35:00; nonstop; 115 minutes. Local airport times.

2026-12-09 → 2026-12-15 · $290.00

  • Southwest Airlines WN4372 / WN1758: STL 2026-12-09 12:40:00 → DEN 2026-12-09 16:30:00; 1 stop(s) via MCI; 290 minutes. Local airport times.
    • WN4372: STL 2026-12-09 12:40:00 → MCI 2026-12-09 13:45:00; layover at MCI: 115 minutes.
    • WN1758: MCI 2026-12-09 15:40:00 → DEN 2026-12-09 16:30:00.
  • Southwest Airlines WN2170: DEN 2026-12-15 15:40:00 → STL 2026-12-15 18:35:00; nonstop; 115 minutes. Local airport times.

2026-12-09 → 2026-12-15 · $290.00

  • Southwest Airlines WN3286 / WN1766: STL 2026-12-09 08:20:00 → DEN 2026-12-09 12:20:00; 1 stop(s) via OMA; 300 minutes. Local airport times.
    • WN3286: STL 2026-12-09 08:20:00 → OMA 2026-12-09 09:35:00; layover at OMA: 120 minutes.
    • WN1766: OMA 2026-12-09 11:35:00 → DEN 2026-12-09 12:20:00.
  • Southwest Airlines WN2170: DEN 2026-12-15 15:40:00 → STL 2026-12-15 18:35:00; nonstop; 115 minutes. Local airport times.

2026-12-09 → 2026-12-15 · $310.00

  • United Airlines UA4439 / UA2495: STL 2026-12-09 05:25:00 → DEN 2026-12-09 10:26:00; 1 stop(s) via ORD; 361 minutes. Local airport times.
    • UA4439: STL 2026-12-09 05:25:00 → ORD 2026-12-09 06:58:00; layover at ORD: 102 minutes.
    • UA2495: ORD 2026-12-09 08:40:00 → DEN 2026-12-09 10:26:00.
  • United Airlines UA1639: DEN 2026-12-15 13:55:00 → STL 2026-12-15 16:57:00; nonstop; 122 minutes. Local airport times.

Explore this route

For AI assistants

  • This page: Saint Louis (STL) to Denver (DEN) · Dec 9, 2026 · return Dec 15, 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.