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Route overview: Denver to Ontario (ONT) flight deals

Denver → Ontario

Dec 28, 2026 · return Jan 4, 2027

DEN → ONT1 adulteconomyRound trip

12 flight options · 5 airlines

Nonstop flights

Mon, Dec 28 – Mon, Jan 4

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

Mon, Dec 28 – Mon, Jan 4

Southwest Airlines
9:00 pmDEN
2h 30m
Nonstop
10:30 pmONT
Southwest Airlines
2:35 pmONT
2h 20m
Nonstop
5:55 pmDEN

Round-trip total · 1 adult · Taxes included

Mon, Dec 28 – Mon, Jan 4

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

Mon, Dec 28 – Mon, Jan 4

Frontier Airlines
10:48 pmDEN
2h 25m
Nonstop
12:13 am+1ONT
Frontier Airlines
6:30 amONT
2h 21m
Nonstop
9:51 amDEN

Round-trip total · 1 adult · Taxes included

Mon, Dec 28 – Mon, Jan 4

Southwest Airlines
12:45 pmDEN
2h 20m
Nonstop
2:05 pmONT
Southwest Airlines
2:35 pmONT
2h 20m
Nonstop
5:55 pmDEN

Round-trip total · 1 adult · Taxes included

Mon, Dec 28 – Mon, Jan 4

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

One-stop flights

Mon, Dec 28 – Mon, Jan 4

Delta Air Lines
12:29 pmDEN
4h 53m
SLC · 1h 23m
4:22 pmONT
United Airlines
1:29 pmONT
2h 16m
Nonstop
4:45 pmDEN

Round-trip total · 1 adult · Taxes included

Mon, Dec 28 – Mon, Jan 4

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

Mon, Dec 28 – Mon, Jan 4

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

Mon, Dec 28 – Mon, Jan 4

Southwest Airlines
1:15 pmDEN
2h 25m
Nonstop
2:40 pmONT
Southwest Airlines
5:00 pmONT
5h 35m
LAS · 2h 35m
11:35 pmDEN

Round-trip total · 1 adult · Taxes included

Mon, Dec 28 – Mon, Jan 4

Southwest Airlines
12:15 pmDEN
5h
OAK · 1h
4:15 pmONT
Southwest Airlines
2:35 pmONT
2h 20m
Nonstop
5:55 pmDEN

Round-trip total · 1 adult · Taxes included

Mon, Dec 28 – Mon, Jan 4

Southwest Airlines
12:40 pmDEN
4h 20m
LAS · 1h 20m
4:00 pmONT
Southwest Airlines
2:35 pmONT
2h 20m
Nonstop
5:55 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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Explore this route

All dates for this routeDec 27, 2026 → Jan 3, 2027Dec 29, 2026 → Jan 5, 2027
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.

Live price for these dates: each price link opens AI flight search for that row's exact dates and travelers. Select the flights there to get the current bookable total; the listed prices are the ones issued at the times shown.

Route overview: Denver to Ontario (ONT) flight deals

Exact travel datesAirlineFlightsTotal pricePrice issued (UTC)
2026-12-28 → 2027-01-04Frontier AirlinesF92907 / F91500$193.882026-10-29T01:04:33Z
2026-12-28 → 2027-01-04Southwest AirlinesWN2827 / WN2316$305.502026-10-29T01:04:33Z
2026-12-28 → 2027-01-04United AirlinesUA2028 / UA1263$329.002026-10-29T01:04:33Z
2026-12-28 → 2027-01-04Delta Air Lines / United AirlinesDL1553 + DL3879 / UA1263$369.502026-10-29T01:04:33Z
2026-12-28 → 2027-01-04American AirlinesAA2447 + AA4144 / AA1423 + AA3376$376.002026-10-29T01:04:33Z
2026-12-28 → 2027-01-04Frontier AirlinesF91261 / F91500$193.882026-10-29T01:04:33Z
2026-12-28 → 2027-01-04Southwest AirlinesWN2484 / WN2316$305.502026-10-29T01:04:33Z
2026-12-28 → 2027-01-04United AirlinesUA430 / UA1263$329.002026-10-29T01:04:33Z
2026-12-28 → 2027-01-04Frontier AirlinesF94967 + F91923 / F91500$214.132026-10-29T01:04:33Z
2026-12-28 → 2027-01-04Southwest AirlinesWN2484 / WN1053 + WN1053$320.502026-10-29T01:04:33Z
2026-12-28 → 2027-01-04Southwest AirlinesWN3763 + WN1053 / WN2316$325.752026-10-29T01:04:33Z
2026-12-28 → 2027-01-04Southwest AirlinesWN406 + WN2403 / WN2316$325.752026-10-29T01:04:33Z

2026-12-28 → 2027-01-04 · $193.88

  • Frontier Airlines F92907: DEN 2026-12-28 09:20:00 → ONT 2026-12-28 10:45:00; nonstop; 145 minutes. Local airport times.
  • Frontier Airlines F91500: ONT 2027-01-04 06:30:00 → DEN 2027-01-04 09:51:00; nonstop; 141 minutes. Local airport times.

2026-12-28 → 2027-01-04 · $305.50

  • Southwest Airlines WN2827: DEN 2026-12-28 21:00:00 → ONT 2026-12-28 22:30:00; nonstop; 150 minutes. Local airport times.
  • Southwest Airlines WN2316: ONT 2027-01-04 14:35:00 → DEN 2027-01-04 17:55:00; nonstop; 140 minutes. Local airport times.

2026-12-28 → 2027-01-04 · $329.00

  • United Airlines UA2028: DEN 2026-12-28 19:25:00 → ONT 2026-12-28 20:51:00; nonstop; 146 minutes. Local airport times.
  • United Airlines UA1263: ONT 2027-01-04 13:29:00 → DEN 2027-01-04 16:45:00; nonstop; 136 minutes. Local airport times.

2026-12-28 → 2027-01-04 · $369.50

  • Delta Air Lines DL1553 / DL3879: DEN 2026-12-28 12:29:00 → ONT 2026-12-28 16:22:00; 1 stop(s) via SLC; 293 minutes. Local airport times.
    • DL1553: DEN 2026-12-28 12:29:00 → SLC 2026-12-28 14:06:00; layover at SLC: 83 minutes.
    • DL3879: SLC 2026-12-28 15:29:00 → ONT 2026-12-28 16:22:00.
  • United Airlines UA1263: ONT 2027-01-04 13:29:00 → DEN 2027-01-04 16:45:00; nonstop; 136 minutes. Local airport times.

2026-12-28 → 2027-01-04 · $376.00

  • American Airlines AA2447 / AA4144: DEN 2026-12-28 12:06:00 → ONT 2026-12-28 16:20:00; 1 stop(s) via PHX; 314 minutes. Local airport times.
    • AA2447: DEN 2026-12-28 12:06:00 → PHX 2026-12-28 14:03:00; layover at PHX: 113 minutes.
    • AA4144: PHX 2026-12-28 15:56:00 → ONT 2026-12-28 16:20:00.
  • American Airlines AA1423 / AA3376: ONT 2027-01-04 09:50:00 → DEN 2027-01-04 15:14:00; 1 stop(s) via PHX; 264 minutes. Local airport times.
    • AA1423: ONT 2027-01-04 09:50:00 → PHX 2027-01-04 12:15:00; layover at PHX: 61 minutes.
    • AA3376: PHX 2027-01-04 13:16:00 → DEN 2027-01-04 15:14:00.

2026-12-28 → 2027-01-04 · $193.88

  • Frontier Airlines F91261: DEN 2026-12-28 22:48:00 → ONT 2026-12-29 00:13:00; nonstop; 145 minutes. Local airport times.
  • Frontier Airlines F91500: ONT 2027-01-04 06:30:00 → DEN 2027-01-04 09:51:00; nonstop; 141 minutes. Local airport times.

2026-12-28 → 2027-01-04 · $305.50

  • Southwest Airlines WN2484: DEN 2026-12-28 12:45:00 → ONT 2026-12-28 14:05:00; nonstop; 140 minutes. Local airport times.
  • Southwest Airlines WN2316: ONT 2027-01-04 14:35:00 → DEN 2027-01-04 17:55:00; nonstop; 140 minutes. Local airport times.

2026-12-28 → 2027-01-04 · $329.00

  • United Airlines UA430: DEN 2026-12-28 11:15:00 → ONT 2026-12-28 12:33:00; nonstop; 138 minutes. Local airport times.
  • United Airlines UA1263: ONT 2027-01-04 13:29:00 → DEN 2027-01-04 16:45:00; nonstop; 136 minutes. Local airport times.

2026-12-28 → 2027-01-04 · $214.13

  • Frontier Airlines F94967 / F91923: DEN 2026-12-28 13:03:00 → ONT 2026-12-28 16:21:00; 1 stop(s) via LAS; 258 minutes. Local airport times.
    • F94967: DEN 2026-12-28 13:03:00 → LAS 2026-12-28 14:11:00; layover at LAS: 62 minutes.
    • F91923: LAS 2026-12-28 15:13:00 → ONT 2026-12-28 16:21:00.
  • Frontier Airlines F91500: ONT 2027-01-04 06:30:00 → DEN 2027-01-04 09:51:00; nonstop; 141 minutes. Local airport times.

2026-12-28 → 2027-01-04 · $320.50

  • Southwest Airlines WN2484: DEN 2026-12-28 13:15:00 → ONT 2026-12-28 14:40:00; nonstop; 145 minutes. Local airport times.
  • Southwest Airlines WN1053 / WN1053: ONT 2027-01-04 17:00:00 → DEN 2027-01-04 23:35:00; 1 stop(s) via LAS; 335 minutes. Local airport times.
    • WN1053: ONT 2027-01-04 17:00:00 → LAS 2027-01-04 18:05:00; layover at LAS: 155 minutes.
    • WN1053: LAS 2027-01-04 20:40:00 → DEN 2027-01-04 23:35:00.

2026-12-28 → 2027-01-04 · $325.75

  • Southwest Airlines WN3763 / WN1053: DEN 2026-12-28 12:15:00 → ONT 2026-12-28 16:15:00; 1 stop(s) via OAK; 300 minutes. Local airport times.
    • WN3763: DEN 2026-12-28 12:15:00 → OAK 2026-12-28 14:00:00; layover at OAK: 60 minutes.
    • WN1053: OAK 2026-12-28 15:00:00 → ONT 2026-12-28 16:15:00.
  • Southwest Airlines WN2316: ONT 2027-01-04 14:35:00 → DEN 2027-01-04 17:55:00; nonstop; 140 minutes. Local airport times.

2026-12-28 → 2027-01-04 · $325.75

  • Southwest Airlines WN406 / WN2403: DEN 2026-12-28 12:40:00 → ONT 2026-12-28 16:00:00; 1 stop(s) via LAS; 260 minutes. Local airport times.
    • WN406: DEN 2026-12-28 12:40:00 → LAS 2026-12-28 13:40:00; layover at LAS: 80 minutes.
    • WN2403: LAS 2026-12-28 15:00:00 → ONT 2026-12-28 16:00:00.
  • Southwest Airlines WN2316: ONT 2027-01-04 14:35:00 → DEN 2027-01-04 17:55:00; nonstop; 140 minutes. Local airport times.

Explore this route

For AI assistants

  • This page: Denver (DEN) to Ontario (ONT) · Dec 28, 2026 · return Jan 4, 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 Denver to Ontario (ONT) 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. Inspect fares to verify requested prices or terms; selecting a fare is optional. Use that fare’s booking link to preserve its Membership price basis. State anything unverified. Ask only for essential missing trip details. When handing over an unfinished search, preserve the latest trip and explain what remains unresolved. Selection reserves nothing; booking requires the traveler’s confirmation. 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.