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Denver → Ontario

Dec 15, 2026 · return Dec 29, 2026

DEN → ONT1 adulteconomyRound trip

12 flight options · 5 airlines

Nonstop flights

Tue, Dec 15 – Tue, Dec 29

Frontier Airlines
8:55 pmDEN
2h 22m
Nonstop
10:17 pmONT
Frontier Airlines
6:30 amONT
2h 21m
Nonstop
9:51 amDEN

Round-trip total · 1 adult · Taxes included

Tue, Dec 15 – Tue, Dec 29

Southwest Airlines
8:50 amDEN
2h 20m
Nonstop
10:10 amONT
Southwest Airlines
6:50 amONT
2h 10m
Nonstop
10:00 amDEN

Round-trip total · 1 adult · Taxes included

Tue, Dec 15 – Tue, Dec 29

United Airlines
11:15 amDEN
2h 18m
Nonstop
12:33 pmONT
United Airlines
1:40 pmONT
2h 15m
Nonstop
4:55 pmDEN

Round-trip total · 1 adult · Taxes included

Tue, Dec 15 – Tue, Dec 29

Frontier Airlines
9:20 amDEN
2h 25m
Nonstop
10:45 amONT
Frontier Airlines
6:30 amONT
2h 21m
Nonstop
9:51 amDEN

Round-trip total · 1 adult · Taxes included

Tue, Dec 15 – Tue, Dec 29

Southwest Airlines
8:15 pmDEN
2h 30m
Nonstop
9:45 pmONT
Southwest Airlines
6:50 amONT
2h 10m
Nonstop
10:00 amDEN

Round-trip total · 1 adult · Taxes included

Tue, Dec 15 – Tue, Dec 29

United Airlines
7:25 pmDEN
2h 26m
Nonstop
8:51 pmONT
United Airlines
1:40 pmONT
2h 15m
Nonstop
4:55 pmDEN

Round-trip total · 1 adult · Taxes included

One-stop flights

Tue, Dec 15 – Tue, Dec 29

Delta Air Lines
12:29 pmDEN
4h 53m
SLC · 1h 23m
4:22 pmONT
Southwest Airlines
6:50 amONT
2h 10m
Nonstop
10:00 amDEN

Round-trip total · 1 adult · Taxes included

Tue, Dec 15 – Tue, Dec 29

American Airlines
12:06 pmDEN
5h 14m
PHX · 1h 53m
4:20 pmONT
American Airlines
9:50 amONT
4h 24m
PHX · 1h 1m
3:14 pmDEN

Round-trip total · 1 adult · Taxes included

Tue, Dec 15 – Tue, Dec 29

Frontier Airlines
1:03 pmDEN
4h 18m
LAS · 1h 2m
4:21 pmONT
Frontier Airlines
6:30 amONT
2h 21m
Nonstop
9:51 amDEN

Round-trip total · 1 adult · Taxes included

Tue, Dec 15 – Tue, Dec 29

Southwest Airlines
12:40 pmDEN
4h 20m
LAS · 1h 20m
4:00 pmONT
Southwest Airlines
6:50 amONT
2h 10m
Nonstop
10:00 amDEN

Round-trip total · 1 adult · Taxes included

Tue, Dec 15 – Tue, Dec 29

Southwest Airlines
6:30 pmDEN
5h 35m
PHX · 2h 20m
11:05 pmONT
Southwest Airlines
6:50 amONT
2h 10m
Nonstop
10:00 amDEN

Round-trip total · 1 adult · Taxes included

Tue, Dec 15 – Tue, Dec 29

Southwest Airlines
12:15 pmDEN
5h
OAK · 1h
4:15 pmONT
Southwest Airlines
6:50 amONT
2h 10m
Nonstop
10:00 amDEN

Round-trip total · 1 adult · Taxes included

Make this trip yours

DEN ⇄ ONT

Economy

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

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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

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)
2026-12-15 → 2026-12-29Frontier AirlinesF91499 / F91500$193.882026-10-29T01:04:33Z
2026-12-15 → 2026-12-29Southwest AirlinesWN2263 / WN3300$305.502026-10-29T01:04:33Z
2026-12-15 → 2026-12-29United AirlinesUA430 / UA1263$329.002026-10-29T01:04:33Z
2026-12-15 → 2026-12-29Delta Air Lines / Southwest AirlinesDL1553 + DL3879 / WN3300$345.502026-10-29T01:04:33Z
2026-12-15 → 2026-12-29American AirlinesAA2447 + AA4144 / AA1423 + AA3376$376.002026-10-29T01:04:33Z
2026-12-15 → 2026-12-29Frontier AirlinesF92907 / F91500$193.882026-10-29T01:04:33Z
2026-12-15 → 2026-12-29Southwest AirlinesWN2827 / WN3300$305.502026-10-29T01:04:33Z
2026-12-15 → 2026-12-29United AirlinesUA2028 / UA1263$329.002026-10-29T01:04:33Z
2026-12-15 → 2026-12-29Frontier AirlinesF94967 + F91923 / F91500$208.882026-10-29T01:04:33Z
2026-12-15 → 2026-12-29Southwest AirlinesWN406 + WN2403 / WN3300$320.502026-10-29T01:04:33Z
2026-12-15 → 2026-12-29Southwest AirlinesWN262 + WN3481 / WN3300$320.502026-10-29T01:04:33Z
2026-12-15 → 2026-12-29Southwest AirlinesWN3763 + WN1053 / WN3300$320.502026-10-29T01:04:33Z

2026-12-15 → 2026-12-29 · $193.88

  • Frontier Airlines F91499: DEN 2026-12-15 20:55:00 → ONT 2026-12-15 22:17:00; nonstop; 142 minutes. Local airport times.
  • Frontier Airlines F91500: ONT 2026-12-29 06:30:00 → DEN 2026-12-29 09:51:00; nonstop; 141 minutes. Local airport times.

2026-12-15 → 2026-12-29 · $305.50

  • Southwest Airlines WN2263: DEN 2026-12-15 08:50:00 → ONT 2026-12-15 10:10:00; nonstop; 140 minutes. Local airport times.
  • Southwest Airlines WN3300: ONT 2026-12-29 06:50:00 → DEN 2026-12-29 10:00:00; nonstop; 130 minutes. Local airport times.

2026-12-15 → 2026-12-29 · $329.00

  • United Airlines UA430: DEN 2026-12-15 11:15:00 → ONT 2026-12-15 12:33:00; nonstop; 138 minutes. Local airport times.
  • United Airlines UA1263: ONT 2026-12-29 13:40:00 → DEN 2026-12-29 16:55:00; nonstop; 135 minutes. Local airport times.

2026-12-15 → 2026-12-29 · $345.50

  • Delta Air Lines DL1553 / DL3879: DEN 2026-12-15 12:29:00 → ONT 2026-12-15 16:22:00; 1 stop(s) via SLC; 293 minutes. Local airport times.
    • DL1553: DEN 2026-12-15 12:29:00 → SLC 2026-12-15 14:06:00; layover at SLC: 83 minutes.
    • DL3879: SLC 2026-12-15 15:29:00 → ONT 2026-12-15 16:22:00.
  • Southwest Airlines WN3300: ONT 2026-12-29 06:50:00 → DEN 2026-12-29 10:00:00; nonstop; 130 minutes. Local airport times.

2026-12-15 → 2026-12-29 · $376.00

  • American Airlines AA2447 / AA4144: DEN 2026-12-15 12:06:00 → ONT 2026-12-15 16:20:00; 1 stop(s) via PHX; 314 minutes. Local airport times.
    • AA2447: DEN 2026-12-15 12:06:00 → PHX 2026-12-15 14:03:00; layover at PHX: 113 minutes.
    • AA4144: PHX 2026-12-15 15:56:00 → ONT 2026-12-15 16:20:00.
  • American Airlines AA1423 / AA3376: ONT 2026-12-29 09:50:00 → DEN 2026-12-29 15:14:00; 1 stop(s) via PHX; 264 minutes. Local airport times.
    • AA1423: ONT 2026-12-29 09:50:00 → PHX 2026-12-29 12:15:00; layover at PHX: 61 minutes.
    • AA3376: PHX 2026-12-29 13:16:00 → DEN 2026-12-29 15:14:00.

2026-12-15 → 2026-12-29 · $193.88

  • Frontier Airlines F92907: DEN 2026-12-15 09:20:00 → ONT 2026-12-15 10:45:00; nonstop; 145 minutes. Local airport times.
  • Frontier Airlines F91500: ONT 2026-12-29 06:30:00 → DEN 2026-12-29 09:51:00; nonstop; 141 minutes. Local airport times.

2026-12-15 → 2026-12-29 · $305.50

  • Southwest Airlines WN2827: DEN 2026-12-15 20:15:00 → ONT 2026-12-15 21:45:00; nonstop; 150 minutes. Local airport times.
  • Southwest Airlines WN3300: ONT 2026-12-29 06:50:00 → DEN 2026-12-29 10:00:00; nonstop; 130 minutes. Local airport times.

2026-12-15 → 2026-12-29 · $329.00

  • United Airlines UA2028: DEN 2026-12-15 19:25:00 → ONT 2026-12-15 20:51:00; nonstop; 146 minutes. Local airport times.
  • United Airlines UA1263: ONT 2026-12-29 13:40:00 → DEN 2026-12-29 16:55:00; nonstop; 135 minutes. Local airport times.

2026-12-15 → 2026-12-29 · $208.88

  • Frontier Airlines F94967 / F91923: DEN 2026-12-15 13:03:00 → ONT 2026-12-15 16:21:00; 1 stop(s) via LAS; 258 minutes. Local airport times.
    • F94967: DEN 2026-12-15 13:03:00 → LAS 2026-12-15 14:11:00; layover at LAS: 62 minutes.
    • F91923: LAS 2026-12-15 15:13:00 → ONT 2026-12-15 16:21:00.
  • Frontier Airlines F91500: ONT 2026-12-29 06:30:00 → DEN 2026-12-29 09:51:00; nonstop; 141 minutes. Local airport times.

2026-12-15 → 2026-12-29 · $320.50

  • Southwest Airlines WN406 / WN2403: DEN 2026-12-15 12:40:00 → ONT 2026-12-15 16:00:00; 1 stop(s) via LAS; 260 minutes. Local airport times.
    • WN406: DEN 2026-12-15 12:40:00 → LAS 2026-12-15 13:40:00; layover at LAS: 80 minutes.
    • WN2403: LAS 2026-12-15 15:00:00 → ONT 2026-12-15 16:00:00.
  • Southwest Airlines WN3300: ONT 2026-12-29 06:50:00 → DEN 2026-12-29 10:00:00; nonstop; 130 minutes. Local airport times.

2026-12-15 → 2026-12-29 · $320.50

  • Southwest Airlines WN262 / WN3481: DEN 2026-12-15 18:30:00 → ONT 2026-12-15 23:05:00; 1 stop(s) via PHX; 335 minutes. Local airport times.
    • WN262: DEN 2026-12-15 18:30:00 → PHX 2026-12-15 20:25:00; layover at PHX: 140 minutes.
    • WN3481: PHX 2026-12-15 22:45:00 → ONT 2026-12-15 23:05:00.
  • Southwest Airlines WN3300: ONT 2026-12-29 06:50:00 → DEN 2026-12-29 10:00:00; nonstop; 130 minutes. Local airport times.

2026-12-15 → 2026-12-29 · $320.50

  • Southwest Airlines WN3763 / WN1053: DEN 2026-12-15 12:15:00 → ONT 2026-12-15 16:15:00; 1 stop(s) via OAK; 300 minutes. Local airport times.
    • WN3763: DEN 2026-12-15 12:15:00 → OAK 2026-12-15 14:00:00; layover at OAK: 60 minutes.
    • WN1053: OAK 2026-12-15 15:00:00 → ONT 2026-12-15 16:15:00.
  • Southwest Airlines WN3300: ONT 2026-12-29 06:50:00 → DEN 2026-12-29 10:00:00; nonstop; 130 minutes. Local airport times.

More dates for this route