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Route overview: Denver to Ontario (ONT) flight deals

Denver → Ontario

Dec 22, 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 22, 2026 · One wayFrontier AirlinesNonstop$114.75 Dec 22, 2026 · One waySouthwest AirlinesNonstop$182.25 Dec 22, 2026 – Dec 23, 2026 · 1 nightFrontier AirlinesNonstop$222.76 Dec 22, 2026 – Dec 23, 2026 · 1 nightSouthwest AirlinesNonstop$351.00 Dec 22, 2026 – Dec 24, 2026 · 2 nightsFrontier AirlinesNonstop$222.76 Dec 22, 2026 – Dec 24, 2026 · 2 nightsDelta Air Lines / Frontier AirlinesUp to 1 stop each way$340.88 Dec 22, 2026 – Dec 25, 2026 · 3 nightsFrontier AirlinesNonstop$222.76 Dec 22, 2026 – Dec 25, 2026 · 3 nightsSouthwest AirlinesNonstop$351.00 Dec 22, 2026 – Dec 26, 2026 · 4 nightsFrontier AirlinesNonstop$222.76 Dec 22, 2026 – Dec 26, 2026 · 4 nightsSouthwest AirlinesNonstop$351.00 Dec 22, 2026 – Dec 27, 2026 · 5 nightsFrontier AirlinesNonstop$222.76 Dec 22, 2026 – Dec 27, 2026 · 5 nightsSouthwest AirlinesNonstop$351.00 Dec 22, 2026 – Dec 28, 2026 · 6 nightsFrontier AirlinesNonstop$222.76 Dec 22, 2026 – Dec 28, 2026 · 6 nightsSouthwest AirlinesNonstop$351.00 Dec 22, 2026 – Dec 29, 2026 · 7 nightsFrontier AirlinesNonstop$222.76 Dec 22, 2026 – Dec 29, 2026 · 7 nightsSouthwest AirlinesNonstop$351.00 Dec 22, 2026 – Dec 30, 2026 · 8 nightsFrontier AirlinesNonstop$222.76 Dec 22, 2026 – Dec 30, 2026 · 8 nightsDelta Air Lines / Frontier AirlinesUp to 1 stop each way$340.88 Dec 22, 2026 – Dec 31, 2026 · 9 nightsFrontier AirlinesNonstop$222.76 Dec 22, 2026 – Dec 31, 2026 · 9 nightsDelta Air Lines / Frontier AirlinesUp to 1 stop each way$340.88 Dec 22, 2026 – Jan 1, 2027 · 10 nightsFrontier AirlinesNonstop$222.76 Dec 22, 2026 – Jan 1, 2027 · 10 nightsDelta Air Lines / Frontier AirlinesUp to 1 stop each way$340.88 Dec 22, 2026 – Jan 2, 2027 · 11 nightsFrontier AirlinesNonstop$222.76 Dec 22, 2026 – Jan 2, 2027 · 11 nightsSouthwest AirlinesNonstop$351.00 Dec 22, 2026 – Jan 3, 2027 · 12 nightsFrontier AirlinesNonstop$222.76 Dec 22, 2026 – Jan 3, 2027 · 12 nightsDelta Air Lines / Frontier AirlinesUp to 1 stop each way$340.88 Dec 22, 2026 – Jan 4, 2027 · 13 nightsFrontier AirlinesNonstop$193.88 Dec 22, 2026 – Jan 4, 2027 · 13 nightsSouthwest AirlinesNonstop$305.50 Dec 22, 2026 – Jan 5, 2027 · 14 nightsFrontier AirlinesNonstop$193.88 Dec 22, 2026 – Jan 5, 2027 · 14 nightsSouthwest AirlinesNonstop$305.50

Flights for your trip

  1. Tue, Dec 22 · One way

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

    One-way total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  2. Tue, Dec 22 · One way

    Southwest Airlines
    8:15 pmDEN
    2h 30m
    Nonstop
    9:45 pmONT

    One-way total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  3. Tue, Dec 22 – Wed, Dec 23

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

  4. Tue, Dec 22 – Wed, Dec 23

    Southwest Airlines
    8:15 pmDEN
    2h 30m
    Nonstop
    9:45 pmONT
    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. Tue, Dec 22 – Thu, Dec 24

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

  6. Tue, Dec 22 – Thu, Dec 24

    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.

  7. Tue, Dec 22 – Fri, Dec 25

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

  8. Tue, Dec 22 – Fri, Dec 25

    Southwest Airlines
    8:15 pmDEN
    2h 30m
    Nonstop
    9:45 pmONT
    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.

  9. Tue, Dec 22 – Sat, Dec 26

    Frontier Airlines
    9:20 amDEN
    2h 25m
    Nonstop
    10:45 amONT
    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. Tue, Dec 22 – Sat, Dec 26

    Southwest Airlines
    8:15 pmDEN
    2h 30m
    Nonstop
    9:45 pmONT
    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.

  11. Tue, Dec 22 – Mon, Dec 28

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

  12. Tue, Dec 22 – Mon, Dec 28

    Southwest Airlines
    8:15 pmDEN
    2h 30m
    Nonstop
    9:45 pmONT
    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.

  13. Tue, Dec 22 – Tue, Dec 29

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

  14. Tue, Dec 22 – Tue, Dec 29

    Southwest Airlines
    8:15 pmDEN
    2h 30m
    Nonstop
    9:45 pmONT
    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.

  15. Tue, Dec 22 – Wed, Dec 30

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

  16. Tue, Dec 22 – 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.

  17. Tue, Dec 22 – Fri, Jan 1

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

  18. Tue, Dec 22 – 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.

  19. Tue, Dec 22 – Sat, Jan 2

    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

    Availability is checked when you select these flights.

  20. Tue, Dec 22 – Sat, Jan 2

    Southwest Airlines
    8:15 pmDEN
    2h 30m
    Nonstop
    9:45 pmONT
    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.

  21. Tue, Dec 22 – Sun, Jan 3

    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

    Availability is checked when you select these flights.

  22. Tue, Dec 22 – 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.

  23. Tue, Dec 22 – Tue, Jan 5

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

  24. Tue, Dec 22 – Tue, Jan 5

    Southwest Airlines
    8:15 pmDEN
    2h 30m
    Nonstop
    9:45 pmONT
    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.

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 21, 2026 · Return optionsDec 23, 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)
2026-12-22 · one wayFrontier AirlinesF92907Axel-exclusive $114.752026-10-29T01:04:33Z
2026-12-22 · one waySouthwest AirlinesWN2827Axel-exclusive $182.252026-10-29T01:04:33Z
2026-12-22 → 2026-12-23Frontier AirlinesF92907 / F92908Axel-exclusive $222.762026-10-29T01:04:33Z
2026-12-22 → 2026-12-23Southwest AirlinesWN2827 / WN2316Axel-exclusive $351.002026-10-29T01:04:33Z
2026-12-22 → 2026-12-24Frontier AirlinesF92907 / F92908Axel-exclusive $222.762026-10-29T01:04:33Z
2026-12-22 → 2026-12-24Delta Air Lines / Frontier AirlinesDL1553 + DL3879 / F92908Axel-exclusive $340.882026-10-29T01:04:33Z
2026-12-22 → 2026-12-25Frontier AirlinesF92907 / F92908Axel-exclusive $222.762026-10-29T01:04:33Z
2026-12-22 → 2026-12-25Southwest AirlinesWN2827 / WN2316Axel-exclusive $351.002026-10-29T01:04:33Z
2026-12-22 → 2026-12-26Frontier AirlinesF92907 / F92908Axel-exclusive $222.762026-10-29T01:04:33Z
2026-12-22 → 2026-12-26Southwest AirlinesWN2827 / WN3301Axel-exclusive $351.002026-10-29T01:04:33Z
2026-12-22 → 2026-12-27Frontier AirlinesF92907 / F92908Axel-exclusive $222.762026-10-29T01:04:33Z
2026-12-22 → 2026-12-27Southwest AirlinesWN2827 / WN2316Axel-exclusive $351.002026-10-29T01:04:33Z
2026-12-22 → 2026-12-28Frontier AirlinesF92907 / F92908Axel-exclusive $222.762026-10-29T01:04:33Z
2026-12-22 → 2026-12-28Southwest AirlinesWN2827 / WN2316Axel-exclusive $351.002026-10-29T01:04:33Z
2026-12-22 → 2026-12-29Frontier AirlinesF92907 / F92908Axel-exclusive $222.762026-10-29T01:04:33Z
2026-12-22 → 2026-12-29Southwest AirlinesWN2827 / WN3300Axel-exclusive $351.002026-10-29T01:04:33Z
2026-12-22 → 2026-12-30Frontier AirlinesF92907 / F92908Axel-exclusive $222.762026-10-29T01:04:33Z
2026-12-22 → 2026-12-30Delta Air Lines / Frontier AirlinesDL1553 + DL3879 / F92908Axel-exclusive $340.882026-10-29T01:04:33Z
2026-12-22 → 2026-12-31Frontier AirlinesF92907 / F92908Axel-exclusive $222.762026-10-29T01:04:33Z
2026-12-22 → 2026-12-31Delta Air Lines / Frontier AirlinesDL1553 + DL3879 / F92908Axel-exclusive $340.882026-10-29T01:04:33Z
2026-12-22 → 2027-01-01Frontier AirlinesF92907 / F92908Axel-exclusive $222.762026-10-29T01:04:33Z
2026-12-22 → 2027-01-01Delta Air Lines / Frontier AirlinesDL1553 + DL3879 / F92908Axel-exclusive $340.882026-10-29T01:04:33Z
2026-12-22 → 2027-01-02Frontier AirlinesF92907 / F92908Axel-exclusive $222.762026-10-29T01:04:33Z
2026-12-22 → 2027-01-02Southwest AirlinesWN2827 / WN3301Axel-exclusive $351.002026-10-29T01:04:33Z
2026-12-22 → 2027-01-03Frontier AirlinesF92907 / F92908Axel-exclusive $222.762026-10-29T01:04:33Z
2026-12-22 → 2027-01-03Delta Air Lines / Frontier AirlinesDL1553 + DL3879 / F92908Axel-exclusive $340.882026-10-29T01:04:33Z
2026-12-22 → 2027-01-04Frontier AirlinesF92907 / F92908Axel-exclusive $193.882026-10-29T01:04:33Z
2026-12-22 → 2027-01-04Southwest AirlinesWN2827 / WN2316Axel-exclusive $305.502026-10-29T01:04:33Z
2026-12-22 → 2027-01-05Frontier AirlinesF92907 / F92908Axel-exclusive $193.882026-10-29T01:04:33Z
2026-12-22 → 2027-01-05Southwest AirlinesWN2827 / WN3300Axel-exclusive $305.502026-10-29T01:04:33Z

Route overview: Denver to Ontario (ONT) flight deals

2026-12-22 · one way · Axel-exclusive $114.75

  • Frontier Airlines F92907: DEN 2026-12-22 09:20:00 → ONT 2026-12-22 10:45:00; nonstop; 145 minutes. Local airport times.

2026-12-22 · one way · Axel-exclusive $182.25

  • Southwest Airlines WN2827: DEN 2026-12-22 20:15:00 → ONT 2026-12-22 21:45:00; nonstop; 150 minutes. Local airport times.

2026-12-22 → 2026-12-23 · Axel-exclusive $222.76

  • Frontier Airlines F92907: DEN 2026-12-22 09:20:00 → ONT 2026-12-22 10:45:00; nonstop; 145 minutes. Local airport times.
  • Frontier Airlines F92908: ONT 2026-12-23 11:42:00 → DEN 2026-12-23 15:07:00; nonstop; 145 minutes. Local airport times.

2026-12-22 → 2026-12-23 · Axel-exclusive $351.00

  • Southwest Airlines WN2827: DEN 2026-12-22 20:15:00 → ONT 2026-12-22 21:45:00; nonstop; 150 minutes. Local airport times.
  • Southwest Airlines WN2316: ONT 2026-12-23 14:35:00 → DEN 2026-12-23 17:55:00; nonstop; 140 minutes. Local airport times.

2026-12-22 → 2026-12-24 · Axel-exclusive $222.76

  • Frontier Airlines F92907: DEN 2026-12-22 09:20:00 → ONT 2026-12-22 10:45:00; nonstop; 145 minutes. Local airport times.
  • Frontier Airlines F92908: ONT 2026-12-24 11:32:00 → DEN 2026-12-24 14:57:00; nonstop; 145 minutes. Local airport times.

2026-12-22 → 2026-12-24 · Axel-exclusive $340.88

  • Delta Air Lines DL1553 / DL3879: DEN 2026-12-22 12:29:00 → ONT 2026-12-22 16:22:00; 1 stop(s) via SLC; 293 minutes. Local airport times.
    • DL1553: DEN 2026-12-22 12:29:00 → SLC 2026-12-22 14:06:00; layover at SLC: 83 minutes.
    • DL3879: SLC 2026-12-22 15:29:00 → ONT 2026-12-22 16:22:00.
  • Frontier Airlines F92908: ONT 2026-12-24 11:32:00 → DEN 2026-12-24 14:57:00; nonstop; 145 minutes. Local airport times.

2026-12-22 → 2026-12-25 · Axel-exclusive $222.76

  • Frontier Airlines F92907: DEN 2026-12-22 09:20:00 → ONT 2026-12-22 10:45:00; nonstop; 145 minutes. Local airport times.
  • Frontier Airlines F92908: ONT 2026-12-25 11:42:00 → DEN 2026-12-25 15:07:00; nonstop; 145 minutes. Local airport times.

2026-12-22 → 2026-12-25 · Axel-exclusive $351.00

  • Southwest Airlines WN2827: DEN 2026-12-22 20:15:00 → ONT 2026-12-22 21:45:00; nonstop; 150 minutes. Local airport times.
  • Southwest Airlines WN2316: ONT 2026-12-25 14:35:00 → DEN 2026-12-25 17:55:00; nonstop; 140 minutes. Local airport times.

2026-12-22 → 2026-12-26 · Axel-exclusive $222.76

  • Frontier Airlines F92907: DEN 2026-12-22 09:20:00 → ONT 2026-12-22 10:45:00; nonstop; 145 minutes. Local airport times.
  • Frontier Airlines F92908: ONT 2026-12-26 11:42:00 → DEN 2026-12-26 15:07:00; nonstop; 145 minutes. Local airport times.

2026-12-22 → 2026-12-26 · Axel-exclusive $351.00

  • Southwest Airlines WN2827: DEN 2026-12-22 20:15:00 → ONT 2026-12-22 21:45:00; nonstop; 150 minutes. Local airport times.
  • Southwest Airlines WN3301: ONT 2026-12-26 08:45:00 → DEN 2026-12-26 11:55:00; nonstop; 130 minutes. Local airport times.

2026-12-22 → 2026-12-28 · Axel-exclusive $222.76

  • Frontier Airlines F92907: DEN 2026-12-22 09:20:00 → ONT 2026-12-22 10:45:00; nonstop; 145 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.

2026-12-22 → 2026-12-28 · Axel-exclusive $351.00

  • Southwest Airlines WN2827: DEN 2026-12-22 20:15:00 → ONT 2026-12-22 21:45:00; nonstop; 150 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.

2026-12-22 → 2026-12-29 · Axel-exclusive $222.76

  • Frontier Airlines F92907: DEN 2026-12-22 09:20:00 → ONT 2026-12-22 10:45:00; nonstop; 145 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.

2026-12-22 → 2026-12-29 · Axel-exclusive $351.00

  • Southwest Airlines WN2827: DEN 2026-12-22 20:15:00 → ONT 2026-12-22 21:45:00; nonstop; 150 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.

2026-12-22 → 2026-12-30 · Axel-exclusive $222.76

  • Frontier Airlines F92907: DEN 2026-12-22 09:20:00 → ONT 2026-12-22 10:45:00; nonstop; 145 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.

2026-12-22 → 2026-12-30 · Axel-exclusive $340.88

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

2026-12-22 → 2027-01-01 · Axel-exclusive $222.76

  • Frontier Airlines F92907: DEN 2026-12-22 09:20:00 → ONT 2026-12-22 10:45:00; nonstop; 145 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.

2026-12-22 → 2027-01-01 · Axel-exclusive $340.88

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

2026-12-22 → 2027-01-02 · Axel-exclusive $222.76

  • Frontier Airlines F92907: DEN 2026-12-22 09:20:00 → ONT 2026-12-22 10:45:00; nonstop; 145 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.

2026-12-22 → 2027-01-02 · Axel-exclusive $351.00

  • Southwest Airlines WN2827: DEN 2026-12-22 20:15:00 → ONT 2026-12-22 21:45:00; nonstop; 150 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.

2026-12-22 → 2027-01-03 · Axel-exclusive $222.76

  • Frontier Airlines F92907: DEN 2026-12-22 09:20:00 → ONT 2026-12-22 10:45:00; nonstop; 145 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.

2026-12-22 → 2027-01-03 · Axel-exclusive $340.88

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

2026-12-22 → 2027-01-05 · Axel-exclusive $193.88

  • Frontier Airlines F92907: DEN 2026-12-22 09:20:00 → ONT 2026-12-22 10:45:00; nonstop; 145 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.

2026-12-22 → 2027-01-05 · Axel-exclusive $305.50

  • Southwest Airlines WN2827: DEN 2026-12-22 20:15:00 → ONT 2026-12-22 21:45:00; nonstop; 150 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.

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For AI assistants

  • This page: Denver (DEN) to Ontario (ONT) · Dec 22, 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.