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Denver → Ontario

Dec 16, 2026 · return Dec 20, 2026

DEN → ONT1 adulteconomyRound trip

12 flight options · 5 airlines

Nonstop flights

Wed, Dec 16 – Sun, Dec 20

Frontier Airlines
10:48 pmDEN
2h 25m
Nonstop
12:13 am+1ONT
Frontier Airlines
11:16 amONT
2h 25m
Nonstop
2:41 pmDEN

Round-trip total · 1 adult · Taxes included

Wed, Dec 16 – Sun, Dec 20

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

Round-trip total · 1 adult · Taxes included

Wed, Dec 16 – Sun, Dec 20

United Airlines
11:15 amDEN
2h 18m
Nonstop
12:33 pmONT
United Airlines
1:29 pmONT
2h 16m
Nonstop
4:45 pmDEN

Round-trip total · 1 adult · Taxes included

Wed, Dec 16 – Sun, Dec 20

Frontier Airlines
9:20 amDEN
2h 25m
Nonstop
10:45 amONT
Frontier Airlines
11:16 amONT
2h 25m
Nonstop
2:41 pmDEN

Round-trip total · 1 adult · Taxes included

Wed, Dec 16 – Sun, Dec 20

Southwest Airlines
1:15 pmDEN
2h 25m
Nonstop
2:40 pmONT
Southwest Airlines
2:45 pmONT
2h 15m
Nonstop
6:00 pmDEN

Round-trip total · 1 adult · Taxes included

Wed, Dec 16 – Sun, Dec 20

United Airlines
7:25 pmDEN
2h 26m
Nonstop
8:51 pmONT
United Airlines
1:29 pmONT
2h 16m
Nonstop
4:45 pmDEN

Round-trip total · 1 adult · Taxes included

One-stop flights

Wed, Dec 16 – Sun, Dec 20

Delta Air Lines
12:29 pmDEN
4h 53m
SLC · 1h 23m
4:22 pmONT
Southwest Airlines
2:45 pmONT
2h 15m
Nonstop
6:00 pmDEN

Round-trip total · 1 adult · Taxes included

Wed, Dec 16 – Sun, Dec 20

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

Wed, Dec 16 – Sun, Dec 20

Frontier Airlines
1:03 pmDEN
4h 18m
LAS · 1h 2m
4:21 pmONT
Frontier Airlines
11:16 amONT
2h 25m
Nonstop
2:41 pmDEN

Round-trip total · 1 adult · Taxes included

Wed, Dec 16 – Sun, Dec 20

Southwest Airlines
12:15 pmDEN
5h
OAK · 1h
4:15 pmONT
Southwest Airlines
2:45 pmONT
2h 15m
Nonstop
6:00 pmDEN

Round-trip total · 1 adult · Taxes included

Wed, Dec 16 – Sun, Dec 20

Southwest Airlines
6:30 pmDEN
5h 35m
PHX · 2h 20m
11:05 pmONT
Southwest Airlines
2:45 pmONT
2h 15m
Nonstop
6:00 pmDEN

Round-trip total · 1 adult · Taxes included

Wed, Dec 16 – Sun, Dec 20

Southwest Airlines
12:40 pmDEN
4h 20m
LAS · 1h 20m
4:00 pmONT
Southwest Airlines
2:45 pmONT
2h 15m
Nonstop
6:00 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 24, 2026 → Nov 29, 2026Dec 22, 2026 → Dec 27, 2026Dec 30, 2026 → Jan 2, 2027Jan 15, 2027 → Jan 18, 2027Oct 30, 2026 → Nov 2, 2026Oct 31, 2026 → Nov 7, 2026Nov 27, 2026 → Nov 30, 2026Nov 28, 2026 → Dec 5, 2026Dec 25, 2026 → Dec 28, 2026Dec 26, 2026 → Jan 2, 2027Jan 22, 2027 → Jan 25, 2027Oct 30, 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)
2026-12-16 → 2026-12-20Frontier AirlinesF91261 / F92908$193.882026-10-29T01:04:33Z
2026-12-16 → 2026-12-20Southwest AirlinesWN2827 / WN2316$305.502026-10-29T01:04:33Z
2026-12-16 → 2026-12-20United AirlinesUA430 / UA1263$329.002026-10-29T01:04:33Z
2026-12-16 → 2026-12-20Delta Air Lines / Southwest AirlinesDL1553 + DL3879 / WN2316$345.502026-10-29T01:04:33Z
2026-12-16 → 2026-12-20American AirlinesAA2447 + AA4144 / AA1423 + AA3376$376.002026-10-29T01:04:33Z
2026-12-16 → 2026-12-20Frontier AirlinesF92907 / F92908$193.882026-10-29T01:04:33Z
2026-12-16 → 2026-12-20Southwest AirlinesWN2484 / WN2316$305.502026-10-29T01:04:33Z
2026-12-16 → 2026-12-20United AirlinesUA2028 / UA1263$329.002026-10-29T01:04:33Z
2026-12-16 → 2026-12-20Frontier AirlinesF94967 + F91923 / F92908$208.882026-10-29T01:04:33Z
2026-12-16 → 2026-12-20Southwest AirlinesWN3763 + WN1053 / WN2316$320.502026-10-29T01:04:33Z
2026-12-16 → 2026-12-20Southwest AirlinesWN262 + WN3481 / WN2316$320.502026-10-29T01:04:33Z
2026-12-16 → 2026-12-20Southwest AirlinesWN406 + WN2403 / WN2316$320.502026-10-29T01:04:33Z

2026-12-16 → 2026-12-20 · $193.88

  • Frontier Airlines F91261: DEN 2026-12-16 22:48:00 → ONT 2026-12-17 00:13:00; nonstop; 145 minutes. Local airport times.
  • Frontier Airlines F92908: ONT 2026-12-20 11:16:00 → DEN 2026-12-20 14:41:00; nonstop; 145 minutes. Local airport times.

2026-12-16 → 2026-12-20 · $305.50

  • Southwest Airlines WN2827: DEN 2026-12-16 21:00:00 → ONT 2026-12-16 22:30:00; nonstop; 150 minutes. Local airport times.
  • Southwest Airlines WN2316: ONT 2026-12-20 14:45:00 → DEN 2026-12-20 18:00:00; nonstop; 135 minutes. Local airport times.

2026-12-16 → 2026-12-20 · $329.00

  • United Airlines UA430: DEN 2026-12-16 11:15:00 → ONT 2026-12-16 12:33:00; nonstop; 138 minutes. Local airport times.
  • United Airlines UA1263: ONT 2026-12-20 13:29:00 → DEN 2026-12-20 16:45:00; nonstop; 136 minutes. Local airport times.

2026-12-16 → 2026-12-20 · $345.50

  • Delta Air Lines DL1553 / DL3879: DEN 2026-12-16 12:29:00 → ONT 2026-12-16 16:22:00; 1 stop(s) via SLC; 293 minutes. Local airport times.
    • DL1553: DEN 2026-12-16 12:29:00 → SLC 2026-12-16 14:06:00; layover at SLC: 83 minutes.
    • DL3879: SLC 2026-12-16 15:29:00 → ONT 2026-12-16 16:22:00.
  • Southwest Airlines WN2316: ONT 2026-12-20 14:45:00 → DEN 2026-12-20 18:00:00; nonstop; 135 minutes. Local airport times.

2026-12-16 → 2026-12-20 · $376.00

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

2026-12-16 → 2026-12-20 · $193.88

  • Frontier Airlines F92907: DEN 2026-12-16 09:20:00 → ONT 2026-12-16 10:45:00; nonstop; 145 minutes. Local airport times.
  • Frontier Airlines F92908: ONT 2026-12-20 11:16:00 → DEN 2026-12-20 14:41:00; nonstop; 145 minutes. Local airport times.

2026-12-16 → 2026-12-20 · $305.50

  • Southwest Airlines WN2484: DEN 2026-12-16 13:15:00 → ONT 2026-12-16 14:40:00; nonstop; 145 minutes. Local airport times.
  • Southwest Airlines WN2316: ONT 2026-12-20 14:45:00 → DEN 2026-12-20 18:00:00; nonstop; 135 minutes. Local airport times.

2026-12-16 → 2026-12-20 · $329.00

  • United Airlines UA2028: DEN 2026-12-16 19:25:00 → ONT 2026-12-16 20:51:00; nonstop; 146 minutes. Local airport times.
  • United Airlines UA1263: ONT 2026-12-20 13:29:00 → DEN 2026-12-20 16:45:00; nonstop; 136 minutes. Local airport times.

2026-12-16 → 2026-12-20 · $208.88

  • Frontier Airlines F94967 / F91923: DEN 2026-12-16 13:03:00 → ONT 2026-12-16 16:21:00; 1 stop(s) via LAS; 258 minutes. Local airport times.
    • F94967: DEN 2026-12-16 13:03:00 → LAS 2026-12-16 14:11:00; layover at LAS: 62 minutes.
    • F91923: LAS 2026-12-16 15:13:00 → ONT 2026-12-16 16:21:00.
  • Frontier Airlines F92908: ONT 2026-12-20 11:16:00 → DEN 2026-12-20 14:41:00; nonstop; 145 minutes. Local airport times.

2026-12-16 → 2026-12-20 · $320.50

  • Southwest Airlines WN3763 / WN1053: DEN 2026-12-16 12:15:00 → ONT 2026-12-16 16:15:00; 1 stop(s) via OAK; 300 minutes. Local airport times.
    • WN3763: DEN 2026-12-16 12:15:00 → OAK 2026-12-16 14:00:00; layover at OAK: 60 minutes.
    • WN1053: OAK 2026-12-16 15:00:00 → ONT 2026-12-16 16:15:00.
  • Southwest Airlines WN2316: ONT 2026-12-20 14:45:00 → DEN 2026-12-20 18:00:00; nonstop; 135 minutes. Local airport times.

2026-12-16 → 2026-12-20 · $320.50

  • Southwest Airlines WN262 / WN3481: DEN 2026-12-16 18:30:00 → ONT 2026-12-16 23:05:00; 1 stop(s) via PHX; 335 minutes. Local airport times.
    • WN262: DEN 2026-12-16 18:30:00 → PHX 2026-12-16 20:25:00; layover at PHX: 140 minutes.
    • WN3481: PHX 2026-12-16 22:45:00 → ONT 2026-12-16 23:05:00.
  • Southwest Airlines WN2316: ONT 2026-12-20 14:45:00 → DEN 2026-12-20 18:00:00; nonstop; 135 minutes. Local airport times.

2026-12-16 → 2026-12-20 · $320.50

  • Southwest Airlines WN406 / WN2403: DEN 2026-12-16 12:40:00 → ONT 2026-12-16 16:00:00; 1 stop(s) via LAS; 260 minutes. Local airport times.
    • WN406: DEN 2026-12-16 12:40:00 → LAS 2026-12-16 13:40:00; layover at LAS: 80 minutes.
    • WN2403: LAS 2026-12-16 15:00:00 → ONT 2026-12-16 16:00:00.
  • Southwest Airlines WN2316: ONT 2026-12-20 14:45:00 → DEN 2026-12-20 18:00:00; nonstop; 135 minutes. Local airport times.

More dates for this route