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Route overview: Denver to Ontario (ONT) flight deals

Denver → Ontario

Dec 26, 2026 · choose your return date

DEN → ONT1 adulteconomyOne way and round trips

30 flight options · 3 airlines

Choose your return date

One-way flights and round trips by duration. Flights for 1 adult in economy. Prices are total for all travelers in USD, including required taxes. Basic economy may apply.

December 2026

Dec 26, 2026 · One wayFrontier AirlinesNonstop$114.75 Dec 26, 2026 · One waySouthwest AirlinesNonstop$182.25 Dec 26, 2026 – Dec 27, 2026 · 1 nightFrontier AirlinesNonstop$222.76 Dec 26, 2026 – Dec 27, 2026 · 1 nightSouthwest AirlinesNonstop$351.00 Dec 26, 2026 – Dec 28, 2026 · 2 nightsFrontier AirlinesNonstop$222.76 Dec 26, 2026 – Dec 28, 2026 · 2 nightsSouthwest AirlinesNonstop$351.00 Dec 26, 2026 – Dec 29, 2026 · 3 nightsFrontier AirlinesNonstop$222.76 Dec 26, 2026 – Dec 29, 2026 · 3 nightsSouthwest AirlinesNonstop$351.00 Dec 26, 2026 – Dec 30, 2026 · 4 nightsFrontier AirlinesNonstop$222.76 Dec 26, 2026 – Dec 30, 2026 · 4 nightsDelta Air Lines / Frontier AirlinesUp to 1 stop each way$340.88 Dec 26, 2026 – Dec 31, 2026 · 5 nightsFrontier AirlinesNonstop$222.76 Dec 26, 2026 – Dec 31, 2026 · 5 nightsDelta Air Lines / Frontier AirlinesUp to 1 stop each way$340.88 Dec 26, 2026 – Jan 1, 2027 · 6 nightsFrontier AirlinesNonstop$222.76 Dec 26, 2026 – Jan 1, 2027 · 6 nightsDelta Air Lines / Frontier AirlinesUp to 1 stop each way$340.88 Dec 26, 2026 – Jan 2, 2027 · 7 nightsFrontier AirlinesNonstop$222.76 Dec 26, 2026 – Jan 2, 2027 · 7 nightsSouthwest AirlinesNonstop$351.00 Dec 26, 2026 – Jan 3, 2027 · 8 nightsFrontier AirlinesNonstop$222.76 Dec 26, 2026 – Jan 3, 2027 · 8 nightsDelta Air Lines / Frontier AirlinesUp to 1 stop each way$340.88 Dec 26, 2026 – Jan 4, 2027 · 9 nightsFrontier AirlinesNonstop$193.88 Dec 26, 2026 – Jan 4, 2027 · 9 nightsSouthwest AirlinesNonstop$305.50 Dec 26, 2026 – Jan 5, 2027 · 10 nightsFrontier AirlinesNonstop$193.88 Dec 26, 2026 – Jan 5, 2027 · 10 nightsSouthwest AirlinesNonstop$305.50 Dec 26, 2026 – Jan 6, 2027 · 11 nightsFrontier AirlinesNonstop$193.88 Dec 26, 2026 – Jan 6, 2027 · 11 nightsSouthwest AirlinesNonstop$305.50 Dec 26, 2026 – Jan 7, 2027 · 12 nightsFrontier AirlinesNonstop$193.88 Dec 26, 2026 – Jan 7, 2027 · 12 nightsSouthwest AirlinesNonstop$305.50 Dec 26, 2026 – Jan 8, 2027 · 13 nightsFrontier AirlinesNonstop$193.88 Dec 26, 2026 – Jan 8, 2027 · 13 nightsSouthwest AirlinesNonstop$305.50 Dec 26, 2026 – Jan 9, 2027 · 14 nightsFrontier AirlinesNonstop$193.88 Dec 26, 2026 – Jan 9, 2027 · 14 nightsSouthwest AirlinesNonstop$305.50

Flights for your trip

  1. Sat, Dec 26 · One way

    Frontier Airlines
    10:52 pmDEN
    2h 22m
    Nonstop
    12:14 am+1ONT

    One-way total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  2. Sat, Dec 26 · One way

    Southwest Airlines
    8:35 amDEN
    2h 25m
    Nonstop
    10:00 amONT

    One-way total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  3. Sat, Dec 26 – Sun, Dec 27

    Frontier Airlines
    10:52 pmDEN
    2h 22m
    Nonstop
    12:14 am+1ONT
    Frontier Airlines
    11:16 amONT
    2h 25m
    Nonstop
    2:41 pmDEN

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  4. Sat, Dec 26 – Sun, Dec 27

    Southwest Airlines
    8:35 amDEN
    2h 25m
    Nonstop
    10:00 amONT
    Southwest Airlines
    2:35 pmONT
    2h 20m
    Nonstop
    5:55 pmDEN

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  5. Sat, Dec 26 – Mon, Dec 28

    Frontier Airlines
    10:52 pmDEN
    2h 22m
    Nonstop
    12:14 am+1ONT
    Frontier Airlines
    11:42 amONT
    2h 25m
    Nonstop
    3:07 pmDEN

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  6. Sat, Dec 26 – Mon, Dec 28

    Southwest Airlines
    8:35 amDEN
    2h 25m
    Nonstop
    10:00 amONT
    Southwest Airlines
    2:35 pmONT
    2h 20m
    Nonstop
    5:55 pmDEN

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  7. Sat, Dec 26 – Tue, Dec 29

    Frontier Airlines
    10:52 pmDEN
    2h 22m
    Nonstop
    12:14 am+1ONT
    Frontier Airlines
    11:30 amONT
    2h 25m
    Nonstop
    2:55 pmDEN

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  8. Sat, Dec 26 – Tue, Dec 29

    Southwest Airlines
    8:35 amDEN
    2h 25m
    Nonstop
    10:00 amONT
    Southwest Airlines
    6:50 amONT
    2h 10m
    Nonstop
    10:00 amDEN

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  9. Sat, Dec 26 – Wed, Dec 30

    Frontier Airlines
    10:52 pmDEN
    2h 22m
    Nonstop
    12:14 am+1ONT
    Frontier Airlines
    11:42 amONT
    2h 25m
    Nonstop
    3:07 pmDEN

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  10. Sat, Dec 26 – Wed, Dec 30

    Delta Air Lines
    12:29 pmDEN
    4h 53m
    SLC · 1h 23m
    4:22 pmONT
    Frontier Airlines
    11:42 amONT
    2h 25m
    Nonstop
    3:07 pmDEN

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  11. Sat, Dec 26 – Fri, Jan 1

    Frontier Airlines
    10:52 pmDEN
    2h 22m
    Nonstop
    12:14 am+1ONT
    Frontier Airlines
    11:32 amONT
    2h 25m
    Nonstop
    2:57 pmDEN

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  12. Sat, Dec 26 – Fri, Jan 1

    Delta Air Lines
    12:29 pmDEN
    4h 53m
    SLC · 1h 23m
    4:22 pmONT
    Frontier Airlines
    11:32 amONT
    2h 25m
    Nonstop
    2:57 pmDEN

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  13. Sat, Dec 26 – Sat, Jan 2

    Frontier Airlines
    10:52 pmDEN
    2h 22m
    Nonstop
    12:14 am+1ONT
    Frontier Airlines
    11:16 amONT
    2h 25m
    Nonstop
    2:41 pmDEN

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  14. Sat, Dec 26 – Sat, Jan 2

    Southwest Airlines
    8:35 amDEN
    2h 25m
    Nonstop
    10:00 amONT
    Southwest Airlines
    8:45 amONT
    2h 10m
    Nonstop
    11:55 amDEN

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  15. Sat, Dec 26 – Sun, Jan 3

    Frontier Airlines
    10:52 pmDEN
    2h 22m
    Nonstop
    12:14 am+1ONT
    Frontier Airlines
    11:16 amONT
    2h 25m
    Nonstop
    2:41 pmDEN

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  16. Sat, Dec 26 – Sun, Jan 3

    Delta Air Lines
    12:29 pmDEN
    4h 53m
    SLC · 1h 23m
    4:22 pmONT
    Frontier Airlines
    11:16 amONT
    2h 25m
    Nonstop
    2:41 pmDEN

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  17. Sat, Dec 26 – Tue, Jan 5

    Frontier Airlines
    10:52 pmDEN
    2h 22m
    Nonstop
    12:14 am+1ONT
    Frontier Airlines
    11:30 amONT
    2h 25m
    Nonstop
    2:55 pmDEN

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  18. Sat, Dec 26 – Tue, Jan 5

    Southwest Airlines
    8:35 amDEN
    2h 25m
    Nonstop
    10:00 amONT
    Southwest Airlines
    6:50 amONT
    2h 10m
    Nonstop
    10:00 amDEN

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  19. Sat, Dec 26 – Wed, Jan 6

    Frontier Airlines
    10:52 pmDEN
    2h 22m
    Nonstop
    12:14 am+1ONT
    Frontier Airlines
    11:42 amONT
    2h 25m
    Nonstop
    3:07 pmDEN

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  20. Sat, Dec 26 – Wed, Jan 6

    Southwest Airlines
    8:35 amDEN
    2h 25m
    Nonstop
    10:00 amONT
    Southwest Airlines
    2:35 pmONT
    2h 20m
    Nonstop
    5:55 pmDEN

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  21. Sat, Dec 26 – Thu, Jan 7

    Frontier Airlines
    10:52 pmDEN
    2h 22m
    Nonstop
    12:14 am+1ONT
    Frontier Airlines
    11:32 amONT
    2h 25m
    Nonstop
    2:57 pmDEN

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  22. Sat, Dec 26 – Thu, Jan 7

    Southwest Airlines
    8:35 amDEN
    2h 25m
    Nonstop
    10:00 amONT
    Southwest Airlines
    2:35 pmONT
    2h 20m
    Nonstop
    5:55 pmDEN

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  23. Sat, Dec 26 – Sat, Jan 9

    Frontier Airlines
    10:52 pmDEN
    2h 22m
    Nonstop
    12:14 am+1ONT
    Frontier Airlines
    11:16 amONT
    2h 25m
    Nonstop
    2:41 pmDEN

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  24. Sat, Dec 26 – Sat, Jan 9

    Southwest Airlines
    8:35 amDEN
    2h 25m
    Nonstop
    10:00 amONT
    Southwest Airlines
    8:45 amONT
    2h 10m
    Nonstop
    11:55 amDEN

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

Swipe to see 23 more recent deals.

1 of 24

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 25, 2026 · Return optionsDec 27, 2026 · Return options
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.

Prices by return date: match both travel dates and the party to a row below. Each total is for that exact trip, issued at the time shown. To book or select flights, follow that row's price link; it keeps the exact dates and travelers.

Exact travel datesAirlineFlightsTotal pricePrice issued (UTC)
2026-12-26 · one wayFrontier AirlinesF91261Axel-exclusive $114.752026-10-29T01:04:33Z
2026-12-26 · one waySouthwest AirlinesWN667Axel-exclusive $182.252026-10-29T01:04:33Z
2026-12-26 → 2026-12-27Frontier AirlinesF91261 / F92908Axel-exclusive $222.762026-10-29T01:04:33Z
2026-12-26 → 2026-12-27Southwest AirlinesWN667 / WN2316Axel-exclusive $351.002026-10-29T01:04:33Z
2026-12-26 → 2026-12-28Frontier AirlinesF91261 / F92908Axel-exclusive $222.762026-10-29T01:04:33Z
2026-12-26 → 2026-12-28Southwest AirlinesWN667 / WN2316Axel-exclusive $351.002026-10-29T01:04:33Z
2026-12-26 → 2026-12-29Frontier AirlinesF91261 / F92908Axel-exclusive $222.762026-10-29T01:04:33Z
2026-12-26 → 2026-12-29Southwest AirlinesWN667 / WN3300Axel-exclusive $351.002026-10-29T01:04:33Z
2026-12-26 → 2026-12-30Frontier AirlinesF91261 / F92908Axel-exclusive $222.762026-10-29T01:04:33Z
2026-12-26 → 2026-12-30Delta Air Lines / Frontier AirlinesDL1553 + DL3879 / F92908Axel-exclusive $340.882026-10-29T01:04:33Z
2026-12-26 → 2026-12-31Frontier AirlinesF91261 / F92908Axel-exclusive $222.762026-10-29T01:04:33Z
2026-12-26 → 2026-12-31Delta Air Lines / Frontier AirlinesDL1553 + DL3879 / F92908Axel-exclusive $340.882026-10-29T01:04:33Z
2026-12-26 → 2027-01-01Frontier AirlinesF91261 / F92908Axel-exclusive $222.762026-10-29T01:04:33Z
2026-12-26 → 2027-01-01Delta Air Lines / Frontier AirlinesDL1553 + DL3879 / F92908Axel-exclusive $340.882026-10-29T01:04:33Z
2026-12-26 → 2027-01-02Frontier AirlinesF91261 / F92908Axel-exclusive $222.762026-10-29T01:04:33Z
2026-12-26 → 2027-01-02Southwest AirlinesWN667 / WN3301Axel-exclusive $351.002026-10-29T01:04:33Z
2026-12-26 → 2027-01-03Frontier AirlinesF91261 / F92908Axel-exclusive $222.762026-10-29T01:04:33Z
2026-12-26 → 2027-01-03Delta Air Lines / Frontier AirlinesDL1553 + DL3879 / F92908Axel-exclusive $340.882026-10-29T01:04:33Z
2026-12-26 → 2027-01-04Frontier AirlinesF91261 / F92908Axel-exclusive $193.882026-10-29T01:04:33Z
2026-12-26 → 2027-01-04Southwest AirlinesWN667 / WN2316Axel-exclusive $305.502026-10-29T01:04:33Z
2026-12-26 → 2027-01-05Frontier AirlinesF91261 / F92908Axel-exclusive $193.882026-10-29T01:04:33Z
2026-12-26 → 2027-01-05Southwest AirlinesWN667 / WN3300Axel-exclusive $305.502026-10-29T01:04:33Z
2026-12-26 → 2027-01-06Frontier AirlinesF91261 / F92908Axel-exclusive $193.882026-10-29T01:04:33Z
2026-12-26 → 2027-01-06Southwest AirlinesWN667 / WN2316Axel-exclusive $305.502026-10-29T01:04:33Z
2026-12-26 → 2027-01-07Frontier AirlinesF91261 / F92908Axel-exclusive $193.882026-10-29T01:04:33Z
2026-12-26 → 2027-01-07Southwest AirlinesWN667 / WN2316Axel-exclusive $305.502026-10-29T01:04:33Z
2026-12-26 → 2027-01-08Frontier AirlinesF91261 / F92908Axel-exclusive $193.882026-10-29T01:04:33Z
2026-12-26 → 2027-01-08Southwest AirlinesWN667 / WN2316Axel-exclusive $305.502026-10-29T01:04:33Z
2026-12-26 → 2027-01-09Frontier AirlinesF91261 / F92908Axel-exclusive $193.882026-10-29T01:04:33Z
2026-12-26 → 2027-01-09Southwest AirlinesWN667 / WN3301Axel-exclusive $305.502026-10-29T01:04:33Z

Route overview: Denver to Ontario (ONT) flight deals

2026-12-26 · one way · Axel-exclusive $114.75

  • Frontier Airlines F91261: DEN 2026-12-26 22:52:00 → ONT 2026-12-27 00:14:00; nonstop; 142 minutes. Local airport times.

2026-12-26 · one way · Axel-exclusive $182.25

  • Southwest Airlines WN667: DEN 2026-12-26 08:35:00 → ONT 2026-12-26 10:00:00; nonstop; 145 minutes. Local airport times.

2026-12-26 → 2026-12-27 · Axel-exclusive $222.76

  • Frontier Airlines F91261: DEN 2026-12-26 22:52:00 → ONT 2026-12-27 00:14:00; nonstop; 142 minutes. Local airport times.
  • Frontier Airlines F92908: ONT 2026-12-27 11:16:00 → DEN 2026-12-27 14:41:00; nonstop; 145 minutes. Local airport times.

2026-12-26 → 2026-12-27 · Axel-exclusive $351.00

  • Southwest Airlines WN667: DEN 2026-12-26 08:35:00 → ONT 2026-12-26 10:00:00; nonstop; 145 minutes. Local airport times.
  • Southwest Airlines WN2316: ONT 2026-12-27 14:35:00 → DEN 2026-12-27 17:55:00; nonstop; 140 minutes. Local airport times.

2026-12-26 → 2026-12-28 · Axel-exclusive $222.76

  • Frontier Airlines F91261: DEN 2026-12-26 22:52:00 → ONT 2026-12-27 00:14:00; nonstop; 142 minutes. Local airport times.
  • Frontier Airlines F92908: ONT 2026-12-28 11:42:00 → DEN 2026-12-28 15:07:00; nonstop; 145 minutes. Local airport times.

2026-12-26 → 2026-12-28 · Axel-exclusive $351.00

  • Southwest Airlines WN667: DEN 2026-12-26 08:35:00 → ONT 2026-12-26 10:00:00; nonstop; 145 minutes. Local airport times.
  • Southwest Airlines WN2316: ONT 2026-12-28 14:35:00 → DEN 2026-12-28 17:55:00; nonstop; 140 minutes. Local airport times.

2026-12-26 → 2026-12-29 · Axel-exclusive $222.76

  • Frontier Airlines F91261: DEN 2026-12-26 22:52:00 → ONT 2026-12-27 00:14:00; nonstop; 142 minutes. Local airport times.
  • Frontier Airlines F92908: ONT 2026-12-29 11:30:00 → DEN 2026-12-29 14:55:00; nonstop; 145 minutes. Local airport times.

2026-12-26 → 2026-12-29 · Axel-exclusive $351.00

  • Southwest Airlines WN667: DEN 2026-12-26 08:35:00 → ONT 2026-12-26 10:00:00; nonstop; 145 minutes. Local airport times.
  • Southwest Airlines WN3300: ONT 2026-12-29 06:50:00 → DEN 2026-12-29 10:00:00; nonstop; 130 minutes. Local airport times.

2026-12-26 → 2026-12-30 · Axel-exclusive $222.76

  • Frontier Airlines F91261: DEN 2026-12-26 22:52:00 → ONT 2026-12-27 00:14:00; nonstop; 142 minutes. Local airport times.
  • Frontier Airlines F92908: ONT 2026-12-30 11:42:00 → DEN 2026-12-30 15:07:00; nonstop; 145 minutes. Local airport times.

2026-12-26 → 2026-12-30 · Axel-exclusive $340.88

  • Delta Air Lines DL1553 / DL3879: DEN 2026-12-26 12:29:00 → ONT 2026-12-26 16:22:00; 1 stop(s) via SLC; 293 minutes. Local airport times.
    • DL1553: DEN 2026-12-26 12:29:00 → SLC 2026-12-26 14:06:00; layover at SLC: 83 minutes.
    • DL3879: SLC 2026-12-26 15:29:00 → ONT 2026-12-26 16:22:00.
  • Frontier Airlines F92908: ONT 2026-12-30 11:42:00 → DEN 2026-12-30 15:07:00; nonstop; 145 minutes. Local airport times.

2026-12-26 → 2027-01-01 · Axel-exclusive $222.76

  • Frontier Airlines F91261: DEN 2026-12-26 22:52:00 → ONT 2026-12-27 00:14:00; nonstop; 142 minutes. Local airport times.
  • Frontier Airlines F92908: ONT 2027-01-01 11:32:00 → DEN 2027-01-01 14:57:00; nonstop; 145 minutes. Local airport times.

2026-12-26 → 2027-01-01 · Axel-exclusive $340.88

  • Delta Air Lines DL1553 / DL3879: DEN 2026-12-26 12:29:00 → ONT 2026-12-26 16:22:00; 1 stop(s) via SLC; 293 minutes. Local airport times.
    • DL1553: DEN 2026-12-26 12:29:00 → SLC 2026-12-26 14:06:00; layover at SLC: 83 minutes.
    • DL3879: SLC 2026-12-26 15:29:00 → ONT 2026-12-26 16:22:00.
  • Frontier Airlines F92908: ONT 2027-01-01 11:32:00 → DEN 2027-01-01 14:57:00; nonstop; 145 minutes. Local airport times.

2026-12-26 → 2027-01-02 · Axel-exclusive $222.76

  • Frontier Airlines F91261: DEN 2026-12-26 22:52:00 → ONT 2026-12-27 00:14:00; nonstop; 142 minutes. Local airport times.
  • Frontier Airlines F92908: ONT 2027-01-02 11:16:00 → DEN 2027-01-02 14:41:00; nonstop; 145 minutes. Local airport times.

2026-12-26 → 2027-01-02 · Axel-exclusive $351.00

  • Southwest Airlines WN667: DEN 2026-12-26 08:35:00 → ONT 2026-12-26 10:00:00; nonstop; 145 minutes. Local airport times.
  • Southwest Airlines WN3301: ONT 2027-01-02 08:45:00 → DEN 2027-01-02 11:55:00; nonstop; 130 minutes. Local airport times.

2026-12-26 → 2027-01-03 · Axel-exclusive $222.76

  • Frontier Airlines F91261: DEN 2026-12-26 22:52:00 → ONT 2026-12-27 00:14:00; nonstop; 142 minutes. Local airport times.
  • Frontier Airlines F92908: ONT 2027-01-03 11:16:00 → DEN 2027-01-03 14:41:00; nonstop; 145 minutes. Local airport times.

2026-12-26 → 2027-01-03 · Axel-exclusive $340.88

  • Delta Air Lines DL1553 / DL3879: DEN 2026-12-26 12:29:00 → ONT 2026-12-26 16:22:00; 1 stop(s) via SLC; 293 minutes. Local airport times.
    • DL1553: DEN 2026-12-26 12:29:00 → SLC 2026-12-26 14:06:00; layover at SLC: 83 minutes.
    • DL3879: SLC 2026-12-26 15:29:00 → ONT 2026-12-26 16:22:00.
  • Frontier Airlines F92908: ONT 2027-01-03 11:16:00 → DEN 2027-01-03 14:41:00; nonstop; 145 minutes. Local airport times.

2026-12-26 → 2027-01-05 · Axel-exclusive $193.88

  • Frontier Airlines F91261: DEN 2026-12-26 22:52:00 → ONT 2026-12-27 00:14:00; nonstop; 142 minutes. Local airport times.
  • Frontier Airlines F92908: ONT 2027-01-05 11:30:00 → DEN 2027-01-05 14:55:00; nonstop; 145 minutes. Local airport times.

2026-12-26 → 2027-01-05 · Axel-exclusive $305.50

  • Southwest Airlines WN667: DEN 2026-12-26 08:35:00 → ONT 2026-12-26 10:00:00; nonstop; 145 minutes. Local airport times.
  • Southwest Airlines WN3300: ONT 2027-01-05 06:50:00 → DEN 2027-01-05 10:00:00; nonstop; 130 minutes. Local airport times.

2026-12-26 → 2027-01-06 · Axel-exclusive $193.88

  • Frontier Airlines F91261: DEN 2026-12-26 22:52:00 → ONT 2026-12-27 00:14:00; nonstop; 142 minutes. Local airport times.
  • Frontier Airlines F92908: ONT 2027-01-06 11:42:00 → DEN 2027-01-06 15:07:00; nonstop; 145 minutes. Local airport times.

2026-12-26 → 2027-01-06 · Axel-exclusive $305.50

  • Southwest Airlines WN667: DEN 2026-12-26 08:35:00 → ONT 2026-12-26 10:00:00; nonstop; 145 minutes. Local airport times.
  • Southwest Airlines WN2316: ONT 2027-01-06 14:35:00 → DEN 2027-01-06 17:55:00; nonstop; 140 minutes. Local airport times.

2026-12-26 → 2027-01-07 · Axel-exclusive $193.88

  • Frontier Airlines F91261: DEN 2026-12-26 22:52:00 → ONT 2026-12-27 00:14:00; nonstop; 142 minutes. Local airport times.
  • Frontier Airlines F92908: ONT 2027-01-07 11:32:00 → DEN 2027-01-07 14:57:00; nonstop; 145 minutes. Local airport times.

2026-12-26 → 2027-01-07 · Axel-exclusive $305.50

  • Southwest Airlines WN667: DEN 2026-12-26 08:35:00 → ONT 2026-12-26 10:00:00; nonstop; 145 minutes. Local airport times.
  • Southwest Airlines WN2316: ONT 2027-01-07 14:35:00 → DEN 2027-01-07 17:55:00; nonstop; 140 minutes. Local airport times.

2026-12-26 → 2027-01-09 · Axel-exclusive $193.88

  • Frontier Airlines F91261: DEN 2026-12-26 22:52:00 → ONT 2026-12-27 00:14:00; nonstop; 142 minutes. Local airport times.
  • Frontier Airlines F92908: ONT 2027-01-09 11:16:00 → DEN 2027-01-09 14:41:00; nonstop; 145 minutes. Local airport times.

2026-12-26 → 2027-01-09 · Axel-exclusive $305.50

  • Southwest Airlines WN667: DEN 2026-12-26 08:35:00 → ONT 2026-12-26 10:00:00; nonstop; 145 minutes. Local airport times.
  • Southwest Airlines WN3301: ONT 2027-01-09 08:45:00 → DEN 2027-01-09 11:55:00; nonstop; 130 minutes. Local airport times.

Explore this route

For AI assistants

  • This page: Denver (DEN) to Ontario (ONT) · Dec 26, 2026 · choose your return date: 1 adult in economy, every priced fare with its flights, times and total, each with the time its price was issued.
  • Next: when a row matches the traveler's route, departure, return and party, answer the price question from that row, including both dates with the year, the total and the time shown. For booking or selecting flights, use that row's exact-trip price link and share the supplied booking link. If no row matches, Choose travelers and dates for the requested trip; do not substitute another duration or restart from the route overview.
  • 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. Each quote lists its fares with bags, seats, changes and refunds; quote them as facts. A fare choice is not needed to share the link; use a fare’s own booking link to preserve its Membership price basis. Ask only for essential missing trip details. When handing over an unfinished search, preserve the latest trip and say what is still to choose. 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.