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Denver → Ontario

Dec 17, 2026 · return Dec 23, 2026

DEN → ONT1 adulteconomyRound trip

11 flight options · 5 airlines

Nonstop flights

Thu, Dec 17 – Wed, Dec 23

Frontier Airlines
9:20 amDEN
2h 25m
Nonstop
10:45 amONT
Frontier Airlines
11:40 amONT
2h 21m
Nonstop
3:01 pmDEN

Round-trip total · 1 adult · Taxes included

Thu, Dec 17 – Wed, Dec 23

Southwest Airlines
8:50 amDEN
2h 20m
Nonstop
10:10 amONT
Southwest Airlines
6:20 amONT
2h 15m
Nonstop
9:35 amDEN

Round-trip total · 1 adult · Taxes included

Thu, Dec 17 – Wed, Dec 23

United Airlines
11:16 amDEN
2h 26m
Nonstop
12:42 pmONT
United Airlines
1:40 pmONT
2h 15m
Nonstop
4:55 pmDEN

Round-trip total · 1 adult · Taxes included

Thu, Dec 17 – Wed, Dec 23

Frontier Airlines
8:55 pmDEN
2h 22m
Nonstop
10:17 pmONT
Frontier Airlines
11:40 amONT
2h 21m
Nonstop
3:01 pmDEN

Round-trip total · 1 adult · Taxes included

Thu, Dec 17 – Wed, Dec 23

Southwest Airlines
12:45 pmDEN
2h 20m
Nonstop
2:05 pmONT
Southwest Airlines
6:20 amONT
2h 15m
Nonstop
9:35 amDEN

Round-trip total · 1 adult · Taxes included

One-stop flights

Thu, Dec 17 – Wed, Dec 23

Delta Air Lines
12:29 pmDEN
4h 53m
SLC · 1h 23m
4:22 pmONT
Southwest Airlines
6:20 amONT
2h 15m
Nonstop
9:35 amDEN

Round-trip total · 1 adult · Taxes included

Thu, Dec 17 – Wed, Dec 23

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

Thu, Dec 17 – Wed, Dec 23

Frontier Airlines
1:03 pmDEN
4h 18m
LAS · 1h 2m
4:21 pmONT
Frontier Airlines
11:40 amONT
2h 21m
Nonstop
3:01 pmDEN

Round-trip total · 1 adult · Taxes included

Thu, Dec 17 – Wed, Dec 23

Southwest Airlines
12:40 pmDEN
4h 20m
LAS · 1h 20m
4:00 pmONT
Southwest Airlines
6:20 amONT
2h 15m
Nonstop
9:35 amDEN

Round-trip total · 1 adult · Taxes included

Thu, Dec 17 – Wed, Dec 23

Southwest Airlines
12:15 pmDEN
5h
OAK · 1h
4:15 pmONT
Southwest Airlines
6:20 amONT
2h 15m
Nonstop
9:35 amDEN

Round-trip total · 1 adult · Taxes included

Thu, Dec 17 – Wed, Dec 23

United Airlines
11:15 amDEN
2h 18m
Nonstop
12:33 pmONT
United Airlines
6:00 amONT
5h 9m
SFO · 1h
12:09 pmDEN

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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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)
2026-12-17 → 2026-12-23Frontier AirlinesF92907 / F92908$193.882026-10-29T01:04:33Z
2026-12-17 → 2026-12-23Southwest AirlinesWN2263 / WN3300$305.502026-10-29T01:04:33Z
2026-12-17 → 2026-12-23United AirlinesUA430 / UA1263$329.002026-10-29T01:04:33Z
2026-12-17 → 2026-12-23Delta Air Lines / Southwest AirlinesDL1553 + DL3879 / WN3300$345.502026-10-29T01:04:33Z
2026-12-17 → 2026-12-23American AirlinesAA2447 + AA4144 / AA1423 + AA3376$376.002026-10-29T01:04:33Z
2026-12-17 → 2026-12-23Frontier AirlinesF91499 / F92908$193.882026-10-29T01:04:33Z
2026-12-17 → 2026-12-23Southwest AirlinesWN2484 / WN3300$305.502026-10-29T01:04:33Z
2026-12-17 → 2026-12-23Frontier AirlinesF94967 + F91923 / F92908$208.882026-10-29T01:04:33Z
2026-12-17 → 2026-12-23Southwest AirlinesWN406 + WN2403 / WN3300$320.502026-10-29T01:04:33Z
2026-12-17 → 2026-12-23Southwest AirlinesWN3763 + WN1053 / WN3300$320.502026-10-29T01:04:33Z
2026-12-17 → 2026-12-23United AirlinesUA430 / UA2363 + UA1068$349.252026-10-29T01:04:33Z

2026-12-17 → 2026-12-23 · $193.88

  • Frontier Airlines F92907: DEN 2026-12-17 09:20:00 → ONT 2026-12-17 10:45:00; nonstop; 145 minutes. Local airport times.
  • Frontier Airlines F92908: ONT 2026-12-23 11:40:00 → DEN 2026-12-23 15:01:00; nonstop; 141 minutes. Local airport times.

2026-12-17 → 2026-12-23 · $305.50

  • Southwest Airlines WN2263: DEN 2026-12-17 08:50:00 → ONT 2026-12-17 10:10:00; nonstop; 140 minutes. Local airport times.
  • Southwest Airlines WN3300: ONT 2026-12-23 06:20:00 → DEN 2026-12-23 09:35:00; nonstop; 135 minutes. Local airport times.

2026-12-17 → 2026-12-23 · $329.00

  • United Airlines UA430: DEN 2026-12-17 11:16:00 → ONT 2026-12-17 12:42:00; nonstop; 146 minutes. Local airport times.
  • United Airlines UA1263: ONT 2026-12-23 13:40:00 → DEN 2026-12-23 16:55:00; nonstop; 135 minutes. Local airport times.

2026-12-17 → 2026-12-23 · $345.50

  • Delta Air Lines DL1553 / DL3879: DEN 2026-12-17 12:29:00 → ONT 2026-12-17 16:22:00; 1 stop(s) via SLC; 293 minutes. Local airport times.
    • DL1553: DEN 2026-12-17 12:29:00 → SLC 2026-12-17 14:06:00; layover at SLC: 83 minutes.
    • DL3879: SLC 2026-12-17 15:29:00 → ONT 2026-12-17 16:22:00.
  • Southwest Airlines WN3300: ONT 2026-12-23 06:20:00 → DEN 2026-12-23 09:35:00; nonstop; 135 minutes. Local airport times.

2026-12-17 → 2026-12-23 · $376.00

  • American Airlines AA2447 / AA4144: DEN 2026-12-17 12:06:00 → ONT 2026-12-17 16:20:00; 1 stop(s) via PHX; 314 minutes. Local airport times.
    • AA2447: DEN 2026-12-17 12:06:00 → PHX 2026-12-17 14:03:00; layover at PHX: 113 minutes.
    • AA4144: PHX 2026-12-17 15:56:00 → ONT 2026-12-17 16:20:00.
  • American Airlines AA1423 / AA3376: ONT 2026-12-23 09:50:00 → DEN 2026-12-23 15:14:00; 1 stop(s) via PHX; 264 minutes. Local airport times.
    • AA1423: ONT 2026-12-23 09:50:00 → PHX 2026-12-23 12:15:00; layover at PHX: 61 minutes.
    • AA3376: PHX 2026-12-23 13:16:00 → DEN 2026-12-23 15:14:00.

2026-12-17 → 2026-12-23 · $193.88

  • Frontier Airlines F91499: DEN 2026-12-17 20:55:00 → ONT 2026-12-17 22:17:00; nonstop; 142 minutes. Local airport times.
  • Frontier Airlines F92908: ONT 2026-12-23 11:40:00 → DEN 2026-12-23 15:01:00; nonstop; 141 minutes. Local airport times.

2026-12-17 → 2026-12-23 · $305.50

  • Southwest Airlines WN2484: DEN 2026-12-17 12:45:00 → ONT 2026-12-17 14:05:00; nonstop; 140 minutes. Local airport times.
  • Southwest Airlines WN3300: ONT 2026-12-23 06:20:00 → DEN 2026-12-23 09:35:00; nonstop; 135 minutes. Local airport times.

2026-12-17 → 2026-12-23 · $208.88

  • Frontier Airlines F94967 / F91923: DEN 2026-12-17 13:03:00 → ONT 2026-12-17 16:21:00; 1 stop(s) via LAS; 258 minutes. Local airport times.
    • F94967: DEN 2026-12-17 13:03:00 → LAS 2026-12-17 14:11:00; layover at LAS: 62 minutes.
    • F91923: LAS 2026-12-17 15:13:00 → ONT 2026-12-17 16:21:00.
  • Frontier Airlines F92908: ONT 2026-12-23 11:40:00 → DEN 2026-12-23 15:01:00; nonstop; 141 minutes. Local airport times.

2026-12-17 → 2026-12-23 · $320.50

  • Southwest Airlines WN406 / WN2403: DEN 2026-12-17 12:40:00 → ONT 2026-12-17 16:00:00; 1 stop(s) via LAS; 260 minutes. Local airport times.
    • WN406: DEN 2026-12-17 12:40:00 → LAS 2026-12-17 13:40:00; layover at LAS: 80 minutes.
    • WN2403: LAS 2026-12-17 15:00:00 → ONT 2026-12-17 16:00:00.
  • Southwest Airlines WN3300: ONT 2026-12-23 06:20:00 → DEN 2026-12-23 09:35:00; nonstop; 135 minutes. Local airport times.

2026-12-17 → 2026-12-23 · $320.50

  • Southwest Airlines WN3763 / WN1053: DEN 2026-12-17 12:15:00 → ONT 2026-12-17 16:15:00; 1 stop(s) via OAK; 300 minutes. Local airport times.
    • WN3763: DEN 2026-12-17 12:15:00 → OAK 2026-12-17 14:00:00; layover at OAK: 60 minutes.
    • WN1053: OAK 2026-12-17 15:00:00 → ONT 2026-12-17 16:15:00.
  • Southwest Airlines WN3300: ONT 2026-12-23 06:20:00 → DEN 2026-12-23 09:35:00; nonstop; 135 minutes. Local airport times.

2026-12-17 → 2026-12-23 · $349.25

  • United Airlines UA430: DEN 2026-12-17 11:15:00 → ONT 2026-12-17 12:33:00; nonstop; 138 minutes. Local airport times.
  • United Airlines UA2363 / UA1068: ONT 2026-12-23 06:00:00 → DEN 2026-12-23 12:09:00; 1 stop(s) via SFO; 309 minutes. Local airport times.
    • UA2363: ONT 2026-12-23 06:00:00 → SFO 2026-12-23 07:30:00; layover at SFO: 60 minutes.
    • UA1068: SFO 2026-12-23 08:30:00 → DEN 2026-12-23 12:09:00.

More dates for this route