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

Saint Louis → Denver

Jun 13, 2027 · return Jun 25, 2027

STL → DEN1 adulteconomyRound trip

11 flight options · 5 airlines

Nonstop flights

Sun, Jun 13 – Fri, Jun 25

Frontier Airlines
4:21 pmSTL
2h 31m
Nonstop
5:52 pmDEN
Frontier Airlines
12:23 pmDEN
2h 3m
Nonstop
3:26 pmSTL

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Sun, Jun 13 – Fri, Jun 25

Southwest Airlines
6:35 amSTL
2h 25m
Nonstop
8:00 amDEN
Southwest Airlines
9:50 pmDEN
2h
Nonstop
12:50 am+1STL

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Sun, Jun 13 – Fri, Jun 25

United Airlines
8:48 amSTL
2h 38m
Nonstop
10:26 amDEN
United Airlines
5:30 pmDEN
2h 8m
Nonstop
8:38 pmSTL

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Sun, Jun 13 – Fri, Jun 25

Frontier Airlines
7:54 pmSTL
2h 31m
Nonstop
9:25 pmDEN
Frontier Airlines
8:00 amDEN
2h 4m
Nonstop
11:04 amSTL

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Sun, Jun 13 – Fri, Jun 25

United Airlines
6:09 pmSTL
2h 36m
Nonstop
7:45 pmDEN
United Airlines
5:30 pmDEN
2h 8m
Nonstop
8:38 pmSTL

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

One-stop flights

Sun, Jun 13 – Fri, Jun 25

Delta Air Lines
6:03 amSTL
5h
MSP · 1h 7m
10:03 amDEN
American Airlines
1:15 pmDEN
5h 21m
DFW · 1h 35m
7:36 pmSTL

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Sun, Jun 13 – Fri, Jun 25

Frontier Airlines
7:58 pmSTL
2h 31m
Nonstop
9:29 pmDEN
American Airlines
1:15 pmDEN
5h 21m
DFW · 1h 35m
7:36 pmSTL

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Sun, Jun 13 – Fri, Jun 25

Southwest Airlines
6:15 amSTL
2h 25m
Nonstop
7:40 amDEN
Southwest Airlines
6:30 pmDEN
5h 5m
DAL · 1h 20m
12:35 am+1STL

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Sun, Jun 13 – Fri, Jun 25

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

Availability is checked when you select these flights.

Sun, Jun 13 – Fri, Jun 25

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

Availability is checked when you select these flights.

Sun, Jun 13 – Fri, Jun 25

United Airlines
5:25 amSTL
6h 1m
ORD · 1h 42m
10:26 amDEN
United Airlines
5:30 pmDEN
2h 8m
Nonstop
8:38 pmSTL

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

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 routeJun 12, 2027 · Return optionsJun 14, 2027 · Return optionsHotels in Denver with Axel
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.

See flights for these dates: each price link opens AI flight search for that row's exact dates and travelers. Select the complete itinerary there.

Exact travel datesAirlineFlightsTotal pricePrice issued (UTC)
2027-06-13 → 2027-06-25Frontier AirlinesF94567 / F9630Axel-exclusive $205.002026-10-29T01:28:26Z
2027-06-13 → 2027-06-25Southwest AirlinesWN4140 / WN1845Axel-exclusive $330.002026-10-29T01:28:26Z
2027-06-13 → 2027-06-25United AirlinesUA2459 / UA1422Axel-exclusive $350.002026-10-29T01:28:26Z
2027-06-13 → 2027-06-25Delta Air Lines / American AirlinesDL1597 + DL2849 / AA2579 + AA2246Axel-exclusive $395.002026-10-29T01:28:26Z
2027-06-13 → 2027-06-25Frontier AirlinesF94567 / F93302Axel-exclusive $205.002026-10-29T01:28:26Z
2027-06-13 → 2027-06-25United AirlinesUA756 / UA1422Axel-exclusive $350.002026-10-29T01:28:26Z
2027-06-13 → 2027-06-25Frontier Airlines / American AirlinesF94567 / AA2579 + AA2246Axel-exclusive $292.502026-10-29T01:28:26Z
2027-06-13 → 2027-06-25Southwest AirlinesWN4140 / WN235 + WN4472Axel-exclusive $340.002026-10-29T01:28:26Z
2027-06-13 → 2027-06-25Southwest AirlinesWN665 + WN1313 / WN235 + WN4472Axel-exclusive $350.002026-10-29T01:28:26Z
2027-06-13 → 2027-06-25Southwest AirlinesWN4372 + WN1758 / WN235 + WN4472Axel-exclusive $350.002026-10-29T01:28:26Z
2027-06-13 → 2027-06-25United AirlinesUA4439 + UA2495 / UA1422Axel-exclusive $360.002026-10-29T01:28:26Z

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

2027-06-13 → 2027-06-25 · Axel-exclusive $205.00

  • Frontier Airlines F94567: STL 2027-06-13 16:21:00 → DEN 2027-06-13 17:52:00; nonstop; 151 minutes. Local airport times.
  • Frontier Airlines F9630: DEN 2027-06-25 12:23:00 → STL 2027-06-25 15:26:00; nonstop; 123 minutes. Local airport times.

2027-06-13 → 2027-06-25 · Axel-exclusive $330.00

  • Southwest Airlines WN4140: STL 2027-06-13 06:35:00 → DEN 2027-06-13 08:00:00; nonstop; 145 minutes. Local airport times.
  • Southwest Airlines WN1845: DEN 2027-06-25 21:50:00 → STL 2027-06-26 00:50:00; nonstop; 120 minutes. Local airport times.

2027-06-13 → 2027-06-25 · Axel-exclusive $350.00

  • United Airlines UA2459: STL 2027-06-13 08:48:00 → DEN 2027-06-13 10:26:00; nonstop; 158 minutes. Local airport times.
  • United Airlines UA1422: DEN 2027-06-25 17:30:00 → STL 2027-06-25 20:38:00; nonstop; 128 minutes. Local airport times.

2027-06-13 → 2027-06-25 · Axel-exclusive $395.00

  • Delta Air Lines DL1597 / DL2849: STL 2027-06-13 06:03:00 → DEN 2027-06-13 10:03:00; 1 stop(s) via MSP; 300 minutes. Local airport times.
    • DL1597: STL 2027-06-13 06:03:00 → MSP 2027-06-13 07:43:00; layover at MSP: 67 minutes.
    • DL2849: MSP 2027-06-13 08:50:00 → DEN 2027-06-13 10:03:00.
  • American Airlines AA2579 / AA2246: DEN 2027-06-25 13:15:00 → STL 2027-06-25 19:36:00; 1 stop(s) via DFW; 321 minutes. Local airport times.
    • AA2579: DEN 2027-06-25 13:15:00 → DFW 2027-06-25 16:20:00; layover at DFW: 95 minutes.
    • AA2246: DFW 2027-06-25 17:55:00 → STL 2027-06-25 19:36:00.

2027-06-13 → 2027-06-25 · Axel-exclusive $205.00

  • Frontier Airlines F94567: STL 2027-06-13 19:54:00 → DEN 2027-06-13 21:25:00; nonstop; 151 minutes. Local airport times.
  • Frontier Airlines F93302: DEN 2027-06-25 08:00:00 → STL 2027-06-25 11:04:00; nonstop; 124 minutes. Local airport times.

2027-06-13 → 2027-06-25 · Axel-exclusive $350.00

  • United Airlines UA756: STL 2027-06-13 18:09:00 → DEN 2027-06-13 19:45:00; nonstop; 156 minutes. Local airport times.
  • United Airlines UA1422: DEN 2027-06-25 17:30:00 → STL 2027-06-25 20:38:00; nonstop; 128 minutes. Local airport times.

2027-06-13 → 2027-06-25 · Axel-exclusive $292.50

  • Frontier Airlines F94567: STL 2027-06-13 19:58:00 → DEN 2027-06-13 21:29:00; nonstop; 151 minutes. Local airport times.
  • American Airlines AA2579 / AA2246: DEN 2027-06-25 13:15:00 → STL 2027-06-25 19:36:00; 1 stop(s) via DFW; 321 minutes. Local airport times.
    • AA2579: DEN 2027-06-25 13:15:00 → DFW 2027-06-25 16:20:00; layover at DFW: 95 minutes.
    • AA2246: DFW 2027-06-25 17:55:00 → STL 2027-06-25 19:36:00.

2027-06-13 → 2027-06-25 · Axel-exclusive $340.00

  • Southwest Airlines WN4140: STL 2027-06-13 06:15:00 → DEN 2027-06-13 07:40:00; nonstop; 145 minutes. Local airport times.
  • Southwest Airlines WN235 / WN4472: DEN 2027-06-25 18:30:00 → STL 2027-06-26 00:35:00; 1 stop(s) via DAL; 305 minutes. Local airport times.
    • WN235: DEN 2027-06-25 18:30:00 → DAL 2027-06-25 21:30:00; layover at DAL: 80 minutes.
    • WN4472: DAL 2027-06-25 22:50:00 → STL 2027-06-26 00:35:00.

2027-06-13 → 2027-06-25 · Axel-exclusive $350.00

  • Southwest Airlines WN665 / WN1313: STL 2027-06-13 10:35:00 → DEN 2027-06-13 15:05:00; 1 stop(s) via BNA; 330 minutes. Local airport times.
    • WN665: STL 2027-06-13 10:35:00 → BNA 2027-06-13 11:40:00; layover at BNA: 90 minutes.
    • WN1313: BNA 2027-06-13 13:10:00 → DEN 2027-06-13 15:05:00.
  • Southwest Airlines WN235 / WN4472: DEN 2027-06-25 18:30:00 → STL 2027-06-26 00:35:00; 1 stop(s) via DAL; 305 minutes. Local airport times.
    • WN235: DEN 2027-06-25 18:30:00 → DAL 2027-06-25 21:30:00; layover at DAL: 80 minutes.
    • WN4472: DAL 2027-06-25 22:50:00 → STL 2027-06-26 00:35:00.

2027-06-13 → 2027-06-25 · Axel-exclusive $350.00

  • Southwest Airlines WN4372 / WN1758: STL 2027-06-13 12:40:00 → DEN 2027-06-13 16:30:00; 1 stop(s) via MCI; 290 minutes. Local airport times.
    • WN4372: STL 2027-06-13 12:40:00 → MCI 2027-06-13 13:45:00; layover at MCI: 115 minutes.
    • WN1758: MCI 2027-06-13 15:40:00 → DEN 2027-06-13 16:30:00.
  • Southwest Airlines WN235 / WN4472: DEN 2027-06-25 18:30:00 → STL 2027-06-26 00:35:00; 1 stop(s) via DAL; 305 minutes. Local airport times.
    • WN235: DEN 2027-06-25 18:30:00 → DAL 2027-06-25 21:30:00; layover at DAL: 80 minutes.
    • WN4472: DAL 2027-06-25 22:50:00 → STL 2027-06-26 00:35:00.

2027-06-13 → 2027-06-25 · Axel-exclusive $360.00

  • United Airlines UA4439 / UA2495: STL 2027-06-13 05:25:00 → DEN 2027-06-13 10:26:00; 1 stop(s) via ORD; 361 minutes. Local airport times.
    • UA4439: STL 2027-06-13 05:25:00 → ORD 2027-06-13 06:58:00; layover at ORD: 102 minutes.
    • UA2495: ORD 2027-06-13 08:40:00 → DEN 2027-06-13 10:26:00.
  • United Airlines UA1422: DEN 2027-06-25 17:30:00 → STL 2027-06-25 20:38:00; nonstop; 128 minutes. Local airport times.

Explore this route

For AI assistants

  • This page: Saint Louis (STL) to Denver (DEN) · Jun 13, 2027 · return Jun 25, 2027: 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. Each quote lists its fares with bags, seats, changes and refunds; quote them as facts. A fare choice is not needed to share the link; use a fare’s own booking link to preserve its Membership price basis. Ask only for essential missing trip details. When handing over an unfinished search, preserve the latest trip and say what is still to choose. 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.