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Denver → Ontario

Dec 21, 2026 · one way

DEN → ONT1 adulteconomyOne way

12 flight options · 5 airlines

Nonstop flights

Mon, Dec 21 · One way

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

One-way total · 1 adult · Taxes included

Mon, Dec 21 · One way

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

One-way total · 1 adult · Taxes included

Mon, Dec 21 · One way

United Airlines
7:25 pmDEN
2h 26m
Nonstop
8:51 pmONT

One-way total · 1 adult · Taxes included

Mon, Dec 21 · One way

Frontier Airlines
9:20 amDEN
2h 25m
Nonstop
10:45 amONT

One-way total · 1 adult · Taxes included

Mon, Dec 21 · One way

Southwest Airlines
12:45 pmDEN
2h 20m
Nonstop
2:05 pmONT

One-way total · 1 adult · Taxes included

Mon, Dec 21 · One way

United Airlines
11:15 amDEN
2h 18m
Nonstop
12:33 pmONT

One-way total · 1 adult · Taxes included

One-stop flights

Mon, Dec 21 · One way

American Airlines
12:06 pmDEN
5h 14m
PHX · 1h 53m
4:20 pmONT

One-way total · 1 adult · Taxes included

Mon, Dec 21 · One way

Delta Air Lines
12:29 pmDEN
4h 53m
SLC · 1h 23m
4:22 pmONT

One-way total · 1 adult · Taxes included

Mon, Dec 21 · One way

Frontier Airlines
1:03 pmDEN
4h 18m
LAS · 1h 2m
4:21 pmONT

One-way total · 1 adult · Taxes included

Mon, Dec 21 · One way

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

One-way total · 1 adult · Taxes included

Mon, Dec 21 · One way

Southwest Airlines
12:15 pmDEN
5h
OAK · 1h
4:15 pmONT

One-way total · 1 adult · Taxes included

Mon, Dec 21 · One way

Southwest Airlines
12:40 pmDEN
4h 20m
LAS · 1h 20m
4:00 pmONT

One-way 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)
2026-12-21 · one wayFrontier AirlinesF91261$114.752026-10-29T01:04:33Z
2026-12-21 · one waySouthwest AirlinesWN2827$182.252026-10-29T01:04:33Z
2026-12-21 · one wayUnited AirlinesUA2028$195.752026-10-29T01:04:33Z
2026-12-21 · one wayAmerican AirlinesAA2447 + AA4144$222.752026-10-29T01:04:33Z
2026-12-21 · one wayDelta Air LinesDL1553 + DL3879$236.252026-10-29T01:04:33Z
2026-12-21 · one wayFrontier AirlinesF92907$114.752026-10-29T01:04:33Z
2026-12-21 · one waySouthwest AirlinesWN2484$182.252026-10-29T01:04:33Z
2026-12-21 · one wayUnited AirlinesUA430$195.752026-10-29T01:04:33Z
2026-12-21 · one wayFrontier AirlinesF94967 + F91923$135.002026-10-29T01:04:33Z
2026-12-21 · one waySouthwest AirlinesWN262 + WN3481$202.502026-10-29T01:04:33Z
2026-12-21 · one waySouthwest AirlinesWN3763 + WN1053$202.502026-10-29T01:04:33Z
2026-12-21 · one waySouthwest AirlinesWN406 + WN2403$202.502026-10-29T01:04:33Z

2026-12-21 · one way · $114.75

  • Frontier Airlines F91261: DEN 2026-12-21 22:48:00 → ONT 2026-12-22 00:13:00; nonstop; 145 minutes. Local airport times.

2026-12-21 · one way · $182.25

  • Southwest Airlines WN2827: DEN 2026-12-21 21:00:00 → ONT 2026-12-21 22:30:00; nonstop; 150 minutes. Local airport times.

2026-12-21 · one way · $195.75

  • United Airlines UA2028: DEN 2026-12-21 19:25:00 → ONT 2026-12-21 20:51:00; nonstop; 146 minutes. Local airport times.

2026-12-21 · one way · $222.75

  • American Airlines AA2447 / AA4144: DEN 2026-12-21 12:06:00 → ONT 2026-12-21 16:20:00; 1 stop(s) via PHX; 314 minutes. Local airport times.
    • AA2447: DEN 2026-12-21 12:06:00 → PHX 2026-12-21 14:03:00; layover at PHX: 113 minutes.
    • AA4144: PHX 2026-12-21 15:56:00 → ONT 2026-12-21 16:20:00.

2026-12-21 · one way · $236.25

  • Delta Air Lines DL1553 / DL3879: DEN 2026-12-21 12:29:00 → ONT 2026-12-21 16:22:00; 1 stop(s) via SLC; 293 minutes. Local airport times.
    • DL1553: DEN 2026-12-21 12:29:00 → SLC 2026-12-21 14:06:00; layover at SLC: 83 minutes.
    • DL3879: SLC 2026-12-21 15:29:00 → ONT 2026-12-21 16:22:00.

2026-12-21 · one way · $114.75

  • Frontier Airlines F92907: DEN 2026-12-21 09:20:00 → ONT 2026-12-21 10:45:00; nonstop; 145 minutes. Local airport times.

2026-12-21 · one way · $182.25

  • Southwest Airlines WN2484: DEN 2026-12-21 12:45:00 → ONT 2026-12-21 14:05:00; nonstop; 140 minutes. Local airport times.

2026-12-21 · one way · $195.75

  • United Airlines UA430: DEN 2026-12-21 11:15:00 → ONT 2026-12-21 12:33:00; nonstop; 138 minutes. Local airport times.

2026-12-21 · one way · $135.00

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

2026-12-21 · one way · $202.50

  • Southwest Airlines WN262 / WN3481: DEN 2026-12-21 18:30:00 → ONT 2026-12-21 23:05:00; 1 stop(s) via PHX; 335 minutes. Local airport times.
    • WN262: DEN 2026-12-21 18:30:00 → PHX 2026-12-21 20:25:00; layover at PHX: 140 minutes.
    • WN3481: PHX 2026-12-21 22:45:00 → ONT 2026-12-21 23:05:00.

2026-12-21 · one way · $202.50

  • Southwest Airlines WN3763 / WN1053: DEN 2026-12-21 12:15:00 → ONT 2026-12-21 16:15:00; 1 stop(s) via OAK; 300 minutes. Local airport times.
    • WN3763: DEN 2026-12-21 12:15:00 → OAK 2026-12-21 14:00:00; layover at OAK: 60 minutes.
    • WN1053: OAK 2026-12-21 15:00:00 → ONT 2026-12-21 16:15:00.

2026-12-21 · one way · $202.50

  • Southwest Airlines WN406 / WN2403: DEN 2026-12-21 12:40:00 → ONT 2026-12-21 16:00:00; 1 stop(s) via LAS; 260 minutes. Local airport times.
    • WN406: DEN 2026-12-21 12:40:00 → LAS 2026-12-21 13:40:00; layover at LAS: 80 minutes.
    • WN2403: LAS 2026-12-21 15:00:00 → ONT 2026-12-21 16:00:00.

More dates for this route