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Route overview: Denver to Ontario (ONT) flight deals

Denver → Ontario

Dec 27, 2026 · return Dec 30, 2026

DEN → ONT1 adulteconomyRound trip

11 flight options · 5 airlines

Nonstop flights

Sun, Dec 27 – Wed, Dec 30

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

Sun, Dec 27 – Wed, Dec 30

Southwest Airlines
8:30 amDEN
2h 25m
Nonstop
9:55 amONT
Southwest Airlines
6:20 amONT
2h 15m
Nonstop
9:35 amDEN

Round-trip total · 1 adult · Taxes included

Sun, Dec 27 – Wed, Dec 30

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

Sun, Dec 27 – Wed, Dec 30

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

Sun, Dec 27 – Wed, Dec 30

Southwest Airlines
10:45 pmDEN
2h 25m
Nonstop
12:10 am+1ONT
Southwest Airlines
6:20 amONT
2h 15m
Nonstop
9:35 amDEN

Round-trip total · 1 adult · Taxes included

One-stop flights

Sun, Dec 27 – Wed, Dec 30

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

Sun, Dec 27 – Wed, Dec 30

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

Sun, Dec 27 – Wed, Dec 30

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

Sun, Dec 27 – Wed, Dec 30

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

Sun, Dec 27 – Wed, Dec 30

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

Sun, Dec 27 – Wed, Dec 30

United Airlines
11:16 amDEN
2h 26m
Nonstop
12:42 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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Explore this route

All dates for this routeDec 26, 2026 → Dec 29, 2026Dec 28, 2026 → Dec 31, 2026
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)
2026-12-27 → 2026-12-30Frontier AirlinesF92907 / F92908$222.762026-10-29T01:04:33Z
2026-12-27 → 2026-12-30Southwest AirlinesWN2263 / WN3300$351.002026-10-29T01:04:33Z
2026-12-27 → 2026-12-30United AirlinesUA430 / UA1263$378.002026-10-29T01:04:33Z
2026-12-27 → 2026-12-30Delta Air Lines / Southwest AirlinesDL1553 + DL3879 / WN3300$405.002026-10-29T01:04:33Z
2026-12-27 → 2026-12-30American AirlinesAA2447 + AA4144 / AA1423 + AA3376$432.002026-10-29T01:04:33Z
2026-12-27 → 2026-12-30Frontier AirlinesF91499 / F92908$222.762026-10-29T01:04:33Z
2026-12-27 → 2026-12-30Southwest AirlinesWN2392 / WN3300$351.002026-10-29T01:04:33Z
2026-12-27 → 2026-12-30Frontier AirlinesF94967 + F91923 / F92908$243.012026-10-29T01:04:33Z
2026-12-27 → 2026-12-30Southwest AirlinesWN3763 + WN1053 / WN3300$371.252026-10-29T01:04:33Z
2026-12-27 → 2026-12-30Southwest AirlinesWN406 + WN2403 / WN3300$371.252026-10-29T01:04:33Z
2026-12-27 → 2026-12-30United AirlinesUA430 / UA2363 + UA1068$398.252026-10-29T01:04:33Z

2026-12-27 → 2026-12-30 · $222.76

  • Frontier Airlines F92907: DEN 2026-12-27 09:20:00 → ONT 2026-12-27 10:45:00; nonstop; 145 minutes. Local airport times.
  • Frontier Airlines F92908: ONT 2026-12-30 11:40:00 → DEN 2026-12-30 15:01:00; nonstop; 141 minutes. Local airport times.

2026-12-27 → 2026-12-30 · $351.00

  • Southwest Airlines WN2263: DEN 2026-12-27 08:30:00 → ONT 2026-12-27 09:55:00; nonstop; 145 minutes. Local airport times.
  • Southwest Airlines WN3300: ONT 2026-12-30 06:20:00 → DEN 2026-12-30 09:35:00; nonstop; 135 minutes. Local airport times.

2026-12-27 → 2026-12-30 · $378.00

  • United Airlines UA430: DEN 2026-12-27 11:15:00 → ONT 2026-12-27 12:33:00; nonstop; 138 minutes. Local airport times.
  • United Airlines UA1263: ONT 2026-12-30 13:40:00 → DEN 2026-12-30 16:55:00; nonstop; 135 minutes. Local airport times.

2026-12-27 → 2026-12-30 · $405.00

  • Delta Air Lines DL1553 / DL3879: DEN 2026-12-27 12:29:00 → ONT 2026-12-27 16:22:00; 1 stop(s) via SLC; 293 minutes. Local airport times.
    • DL1553: DEN 2026-12-27 12:29:00 → SLC 2026-12-27 14:06:00; layover at SLC: 83 minutes.
    • DL3879: SLC 2026-12-27 15:29:00 → ONT 2026-12-27 16:22:00.
  • Southwest Airlines WN3300: ONT 2026-12-30 06:20:00 → DEN 2026-12-30 09:35:00; nonstop; 135 minutes. Local airport times.

2026-12-27 → 2026-12-30 · $432.00

  • American Airlines AA2447 / AA4144: DEN 2026-12-27 12:06:00 → ONT 2026-12-27 16:20:00; 1 stop(s) via PHX; 314 minutes. Local airport times.
    • AA2447: DEN 2026-12-27 12:06:00 → PHX 2026-12-27 14:03:00; layover at PHX: 113 minutes.
    • AA4144: PHX 2026-12-27 15:56:00 → ONT 2026-12-27 16:20:00.
  • American Airlines AA1423 / AA3376: ONT 2026-12-30 09:50:00 → DEN 2026-12-30 15:14:00; 1 stop(s) via PHX; 264 minutes. Local airport times.
    • AA1423: ONT 2026-12-30 09:50:00 → PHX 2026-12-30 12:15:00; layover at PHX: 61 minutes.
    • AA3376: PHX 2026-12-30 13:16:00 → DEN 2026-12-30 15:14:00.

2026-12-27 → 2026-12-30 · $222.76

  • Frontier Airlines F91499: DEN 2026-12-27 20:55:00 → ONT 2026-12-27 22:17:00; nonstop; 142 minutes. Local airport times.
  • Frontier Airlines F92908: ONT 2026-12-30 11:40:00 → DEN 2026-12-30 15:01:00; nonstop; 141 minutes. Local airport times.

2026-12-27 → 2026-12-30 · $351.00

  • Southwest Airlines WN2392: DEN 2026-12-27 22:45:00 → ONT 2026-12-28 00:10:00; nonstop; 145 minutes. Local airport times.
  • Southwest Airlines WN3300: ONT 2026-12-30 06:20:00 → DEN 2026-12-30 09:35:00; nonstop; 135 minutes. Local airport times.

2026-12-27 → 2026-12-30 · $243.01

  • Frontier Airlines F94967 / F91923: DEN 2026-12-27 13:03:00 → ONT 2026-12-27 16:21:00; 1 stop(s) via LAS; 258 minutes. Local airport times.
    • F94967: DEN 2026-12-27 13:03:00 → LAS 2026-12-27 14:11:00; layover at LAS: 62 minutes.
    • F91923: LAS 2026-12-27 15:13:00 → ONT 2026-12-27 16:21:00.
  • Frontier Airlines F92908: ONT 2026-12-30 11:40:00 → DEN 2026-12-30 15:01:00; nonstop; 141 minutes. Local airport times.

2026-12-27 → 2026-12-30 · $371.25

  • Southwest Airlines WN3763 / WN1053: DEN 2026-12-27 12:15:00 → ONT 2026-12-27 16:15:00; 1 stop(s) via OAK; 300 minutes. Local airport times.
    • WN3763: DEN 2026-12-27 12:15:00 → OAK 2026-12-27 14:00:00; layover at OAK: 60 minutes.
    • WN1053: OAK 2026-12-27 15:00:00 → ONT 2026-12-27 16:15:00.
  • Southwest Airlines WN3300: ONT 2026-12-30 06:20:00 → DEN 2026-12-30 09:35:00; nonstop; 135 minutes. Local airport times.

2026-12-27 → 2026-12-30 · $371.25

  • Southwest Airlines WN406 / WN2403: DEN 2026-12-27 12:40:00 → ONT 2026-12-27 16:00:00; 1 stop(s) via LAS; 260 minutes. Local airport times.
    • WN406: DEN 2026-12-27 12:40:00 → LAS 2026-12-27 13:40:00; layover at LAS: 80 minutes.
    • WN2403: LAS 2026-12-27 15:00:00 → ONT 2026-12-27 16:00:00.
  • Southwest Airlines WN3300: ONT 2026-12-30 06:20:00 → DEN 2026-12-30 09:35:00; nonstop; 135 minutes. Local airport times.

2026-12-27 → 2026-12-30 · $398.25

  • United Airlines UA430: DEN 2026-12-27 11:16:00 → ONT 2026-12-27 12:42:00; nonstop; 146 minutes. Local airport times.
  • United Airlines UA2363 / UA1068: ONT 2026-12-30 06:00:00 → DEN 2026-12-30 12:09:00; 1 stop(s) via SFO; 309 minutes. Local airport times.
    • UA2363: ONT 2026-12-30 06:00:00 → SFO 2026-12-30 07:30:00; layover at SFO: 60 minutes.
    • UA1068: SFO 2026-12-30 08:30:00 → DEN 2026-12-30 12:09:00.

Explore this route

For AI assistants

  • This page: Denver (DEN) to Ontario (ONT) · Dec 27, 2026 · return Dec 30, 2026: 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.