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Route overview: Seattle to Ontario (ONT) flight deals

Seattle → Ontario

Dec 10, 2026 · choose your return date

SEA → ONT1 adulteconomyOne way and round trips

30 flight options · 2 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 10, 2026 · One wayFrontier AirlinesNonstop$85.00 Dec 10, 2026 · One wayAlaska AirlinesNonstop$145.00 Dec 10, 2026 – Dec 11, 2026 · 1 nightFrontier AirlinesNonstop$165.00 Dec 10, 2026 – Dec 11, 2026 · 1 nightAlaska AirlinesNonstop$279.00 Dec 10, 2026 – Dec 12, 2026 · 2 nightsFrontier AirlinesNonstop$165.00 Dec 10, 2026 – Dec 12, 2026 · 2 nightsAlaska AirlinesNonstop$279.00 Dec 10, 2026 – Dec 13, 2026 · 3 nightsFrontier AirlinesNonstop$165.00 Dec 10, 2026 – Dec 13, 2026 · 3 nightsAlaska AirlinesNonstop$279.00 Dec 10, 2026 – Dec 14, 2026 · 4 nightsFrontier AirlinesNonstop$165.00 Dec 10, 2026 – Dec 14, 2026 · 4 nightsAlaska AirlinesNonstop$279.00 Dec 10, 2026 – Dec 15, 2026 · 5 nightsFrontier AirlinesNonstop$165.00 Dec 10, 2026 – Dec 15, 2026 · 5 nightsAlaska AirlinesNonstop$279.00 Dec 10, 2026 – Dec 16, 2026 · 6 nightsFrontier AirlinesNonstop$165.00 Dec 10, 2026 – Dec 16, 2026 · 6 nightsAlaska AirlinesNonstop$279.00 Dec 10, 2026 – Dec 17, 2026 · 7 nightsFrontier AirlinesNonstop$165.00 Dec 10, 2026 – Dec 17, 2026 · 7 nightsAlaska AirlinesNonstop$279.00 Dec 10, 2026 – Dec 18, 2026 · 8 nightsFrontier AirlinesNonstop$165.00 Dec 10, 2026 – Dec 18, 2026 · 8 nightsAlaska AirlinesNonstop$279.00 Dec 10, 2026 – Dec 19, 2026 · 9 nightsFrontier AirlinesNonstop$198.00 Dec 10, 2026 – Dec 19, 2026 · 9 nightsAlaska AirlinesNonstop$334.80 Dec 10, 2026 – Dec 20, 2026 · 10 nightsFrontier AirlinesNonstop$198.00 Dec 10, 2026 – Dec 20, 2026 · 10 nightsAlaska AirlinesNonstop$334.80 Dec 10, 2026 – Dec 21, 2026 · 11 nightsFrontier AirlinesNonstop$198.00 Dec 10, 2026 – Dec 21, 2026 · 11 nightsAlaska AirlinesNonstop$334.80 Dec 10, 2026 – Dec 22, 2026 · 12 nightsFrontier AirlinesNonstop$198.00 Dec 10, 2026 – Dec 22, 2026 · 12 nightsAlaska AirlinesNonstop$334.80 Dec 10, 2026 – Dec 23, 2026 · 13 nightsFrontier AirlinesNonstop$198.00 Dec 10, 2026 – Dec 23, 2026 · 13 nightsAlaska AirlinesNonstop$334.80 Dec 10, 2026 – Dec 24, 2026 · 14 nightsFrontier AirlinesNonstop$198.00 Dec 10, 2026 – Dec 24, 2026 · 14 nightsAlaska AirlinesNonstop$334.80

Flights for your trip

  1. Thu, Dec 10 · One way

    Frontier Airlines
    10:50 amSEA
    2h 48m
    Nonstop
    1:38 pmONT

    One-way total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  2. Thu, Dec 10 · One way

    Alaska Airlines
    1:33 pmSEA
    2h 32m
    Nonstop
    4:05 pmONT

    One-way total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  3. Thu, Dec 10 – Fri, Dec 11

    Frontier Airlines
    10:50 amSEA
    2h 48m
    Nonstop
    1:38 pmONT
    Frontier Airlines
    6:00 amONT
    3h 3m
    Nonstop
    9:03 amSEA

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  4. Thu, Dec 10 – Fri, Dec 11

    Alaska Airlines
    1:33 pmSEA
    2h 32m
    Nonstop
    4:05 pmONT
    Alaska Airlines
    11:57 amONT
    2h 52m
    Nonstop
    2:49 pmSEA

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  5. Thu, Dec 10 – Sat, Dec 12

    Frontier Airlines
    10:50 amSEA
    2h 48m
    Nonstop
    1:38 pmONT
    Frontier Airlines
    6:00 amONT
    3h 3m
    Nonstop
    9:03 amSEA

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  6. Thu, Dec 10 – Sat, Dec 12

    Alaska Airlines
    1:33 pmSEA
    2h 32m
    Nonstop
    4:05 pmONT
    Alaska Airlines
    11:57 amONT
    2h 52m
    Nonstop
    2:49 pmSEA

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  7. Thu, Dec 10 – Sun, Dec 13

    Frontier Airlines
    10:50 amSEA
    2h 48m
    Nonstop
    1:38 pmONT
    Frontier Airlines
    6:00 amONT
    3h 3m
    Nonstop
    9:03 amSEA

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  8. Thu, Dec 10 – Sun, Dec 13

    Alaska Airlines
    1:33 pmSEA
    2h 32m
    Nonstop
    4:05 pmONT
    Alaska Airlines
    11:57 amONT
    2h 52m
    Nonstop
    2:49 pmSEA

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  9. Thu, Dec 10 – Mon, Dec 14

    Frontier Airlines
    10:50 amSEA
    2h 48m
    Nonstop
    1:38 pmONT
    Frontier Airlines
    6:00 amONT
    3h 3m
    Nonstop
    9:03 amSEA

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  10. Thu, Dec 10 – Mon, Dec 14

    Alaska Airlines
    1:33 pmSEA
    2h 32m
    Nonstop
    4:05 pmONT
    Alaska Airlines
    11:57 amONT
    2h 52m
    Nonstop
    2:49 pmSEA

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  11. Thu, Dec 10 – Wed, Dec 16

    Frontier Airlines
    10:50 amSEA
    2h 48m
    Nonstop
    1:38 pmONT
    Frontier Airlines
    6:00 amONT
    3h 3m
    Nonstop
    9:03 amSEA

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  12. Thu, Dec 10 – Wed, Dec 16

    Alaska Airlines
    1:33 pmSEA
    2h 32m
    Nonstop
    4:05 pmONT
    Alaska Airlines
    11:57 amONT
    2h 52m
    Nonstop
    2:49 pmSEA

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  13. Thu, Dec 10 – Thu, Dec 17

    Frontier Airlines
    10:50 amSEA
    2h 48m
    Nonstop
    1:38 pmONT
    Frontier Airlines
    6:00 amONT
    3h 3m
    Nonstop
    9:03 amSEA

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  14. Thu, Dec 10 – Thu, Dec 17

    Alaska Airlines
    1:33 pmSEA
    2h 32m
    Nonstop
    4:05 pmONT
    Alaska Airlines
    11:57 amONT
    2h 52m
    Nonstop
    2:49 pmSEA

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  15. Thu, Dec 10 – Fri, Dec 18

    Frontier Airlines
    10:50 amSEA
    2h 48m
    Nonstop
    1:38 pmONT
    Frontier Airlines
    6:00 amONT
    3h 3m
    Nonstop
    9:03 amSEA

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  16. Thu, Dec 10 – Fri, Dec 18

    Alaska Airlines
    1:33 pmSEA
    2h 32m
    Nonstop
    4:05 pmONT
    Alaska Airlines
    11:57 amONT
    2h 52m
    Nonstop
    2:49 pmSEA

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  17. Thu, Dec 10 – Sun, Dec 20

    Frontier Airlines
    10:50 amSEA
    2h 48m
    Nonstop
    1:38 pmONT
    Frontier Airlines
    6:00 amONT
    3h 3m
    Nonstop
    9:03 amSEA

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  18. Thu, Dec 10 – Sun, Dec 20

    Alaska Airlines
    1:33 pmSEA
    2h 32m
    Nonstop
    4:05 pmONT
    Alaska Airlines
    11:57 amONT
    2h 52m
    Nonstop
    2:49 pmSEA

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  19. Thu, Dec 10 – Mon, Dec 21

    Frontier Airlines
    10:50 amSEA
    2h 48m
    Nonstop
    1:38 pmONT
    Frontier Airlines
    6:00 amONT
    3h 3m
    Nonstop
    9:03 amSEA

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  20. Thu, Dec 10 – Mon, Dec 21

    Alaska Airlines
    1:33 pmSEA
    2h 32m
    Nonstop
    4:05 pmONT
    Alaska Airlines
    11:57 amONT
    2h 52m
    Nonstop
    2:49 pmSEA

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  21. Thu, Dec 10 – Tue, Dec 22

    Frontier Airlines
    10:50 amSEA
    2h 48m
    Nonstop
    1:38 pmONT
    Frontier Airlines
    6:00 amONT
    3h 3m
    Nonstop
    9:03 amSEA

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  22. Thu, Dec 10 – Tue, Dec 22

    Alaska Airlines
    1:33 pmSEA
    2h 32m
    Nonstop
    4:05 pmONT
    Alaska Airlines
    11:57 amONT
    2h 52m
    Nonstop
    2:49 pmSEA

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  23. Thu, Dec 10 – Thu, Dec 24

    Frontier Airlines
    10:50 amSEA
    2h 48m
    Nonstop
    1:38 pmONT
    Frontier Airlines
    6:00 amONT
    3h 3m
    Nonstop
    9:03 amSEA

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  24. Thu, Dec 10 – Thu, Dec 24

    Alaska Airlines
    1:33 pmSEA
    2h 32m
    Nonstop
    4:05 pmONT
    Alaska Airlines
    11:57 amONT
    2h 52m
    Nonstop
    2:49 pmSEA

    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

SEA ⇄ 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 9, 2026 · Return optionsDec 11, 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)
2026-12-10 · one wayFrontier AirlinesF92276Axel-exclusive $85.002026-10-29T01:16:03Z
2026-12-10 · one wayAlaska AirlinesAS571Axel-exclusive $145.002026-10-29T01:16:03Z
2026-12-10 → 2026-12-11Frontier AirlinesF92276 / F92275Axel-exclusive $165.002026-10-29T01:16:03Z
2026-12-10 → 2026-12-11Alaska AirlinesAS571 / AS677Axel-exclusive $279.002026-10-29T01:16:03Z
2026-12-10 → 2026-12-12Frontier AirlinesF92276 / F92275Axel-exclusive $165.002026-10-29T01:16:03Z
2026-12-10 → 2026-12-12Alaska AirlinesAS571 / AS677Axel-exclusive $279.002026-10-29T01:16:03Z
2026-12-10 → 2026-12-13Frontier AirlinesF92276 / F92275Axel-exclusive $165.002026-10-29T01:16:03Z
2026-12-10 → 2026-12-13Alaska AirlinesAS571 / AS677Axel-exclusive $279.002026-10-29T01:16:03Z
2026-12-10 → 2026-12-14Frontier AirlinesF92276 / F92275Axel-exclusive $165.002026-10-29T01:16:03Z
2026-12-10 → 2026-12-14Alaska AirlinesAS571 / AS677Axel-exclusive $279.002026-10-29T01:16:03Z
2026-12-10 → 2026-12-15Frontier AirlinesF92276 / F92275Axel-exclusive $165.002026-10-29T01:16:03Z
2026-12-10 → 2026-12-15Alaska AirlinesAS571 / AS677Axel-exclusive $279.002026-10-29T01:16:03Z
2026-12-10 → 2026-12-16Frontier AirlinesF92276 / F92275Axel-exclusive $165.002026-10-29T01:16:03Z
2026-12-10 → 2026-12-16Alaska AirlinesAS571 / AS677Axel-exclusive $279.002026-10-29T01:16:03Z
2026-12-10 → 2026-12-17Frontier AirlinesF92276 / F92275Axel-exclusive $165.002026-10-29T01:16:03Z
2026-12-10 → 2026-12-17Alaska AirlinesAS571 / AS677Axel-exclusive $279.002026-10-29T01:16:03Z
2026-12-10 → 2026-12-18Frontier AirlinesF92276 / F92275Axel-exclusive $165.002026-10-29T01:16:03Z
2026-12-10 → 2026-12-18Alaska AirlinesAS571 / AS677Axel-exclusive $279.002026-10-29T01:16:03Z
2026-12-10 → 2026-12-19Frontier AirlinesF92276 / F92275Axel-exclusive $198.002026-10-29T01:16:03Z
2026-12-10 → 2026-12-19Alaska AirlinesAS571 / AS677Axel-exclusive $334.802026-10-29T01:16:03Z
2026-12-10 → 2026-12-20Frontier AirlinesF92276 / F92275Axel-exclusive $198.002026-10-29T01:16:03Z
2026-12-10 → 2026-12-20Alaska AirlinesAS571 / AS677Axel-exclusive $334.802026-10-29T01:16:03Z
2026-12-10 → 2026-12-21Frontier AirlinesF92276 / F92275Axel-exclusive $198.002026-10-29T01:16:03Z
2026-12-10 → 2026-12-21Alaska AirlinesAS571 / AS677Axel-exclusive $334.802026-10-29T01:16:03Z
2026-12-10 → 2026-12-22Frontier AirlinesF92276 / F92275Axel-exclusive $198.002026-10-29T01:16:03Z
2026-12-10 → 2026-12-22Alaska AirlinesAS571 / AS677Axel-exclusive $334.802026-10-29T01:16:03Z
2026-12-10 → 2026-12-23Frontier AirlinesF92276 / F92275Axel-exclusive $198.002026-10-29T01:16:03Z
2026-12-10 → 2026-12-23Alaska AirlinesAS571 / AS677Axel-exclusive $334.802026-10-29T01:16:03Z
2026-12-10 → 2026-12-24Frontier AirlinesF92276 / F92275Axel-exclusive $198.002026-10-29T01:16:03Z
2026-12-10 → 2026-12-24Alaska AirlinesAS571 / AS677Axel-exclusive $334.802026-10-29T01:16:03Z

Route overview: Seattle to Ontario (ONT) flight deals

2026-12-10 · one way · Axel-exclusive $85.00

  • Frontier Airlines F92276: SEA 2026-12-10 10:50:00 → ONT 2026-12-10 13:38:00; nonstop; 168 minutes. Local airport times.

2026-12-10 · one way · Axel-exclusive $145.00

  • Alaska Airlines AS571: SEA 2026-12-10 13:33:00 → ONT 2026-12-10 16:05:00; nonstop; 152 minutes. Local airport times.

2026-12-10 → 2026-12-11 · Axel-exclusive $165.00

  • Frontier Airlines F92276: SEA 2026-12-10 10:50:00 → ONT 2026-12-10 13:38:00; nonstop; 168 minutes. Local airport times.
  • Frontier Airlines F92275: ONT 2026-12-11 06:00:00 → SEA 2026-12-11 09:03:00; nonstop; 183 minutes. Local airport times.

2026-12-10 → 2026-12-11 · Axel-exclusive $279.00

  • Alaska Airlines AS571: SEA 2026-12-10 13:33:00 → ONT 2026-12-10 16:05:00; nonstop; 152 minutes. Local airport times.
  • Alaska Airlines AS677: ONT 2026-12-11 11:57:00 → SEA 2026-12-11 14:49:00; nonstop; 172 minutes. Local airport times.

2026-12-10 → 2026-12-12 · Axel-exclusive $165.00

  • Frontier Airlines F92276: SEA 2026-12-10 10:50:00 → ONT 2026-12-10 13:38:00; nonstop; 168 minutes. Local airport times.
  • Frontier Airlines F92275: ONT 2026-12-12 06:00:00 → SEA 2026-12-12 09:03:00; nonstop; 183 minutes. Local airport times.

2026-12-10 → 2026-12-12 · Axel-exclusive $279.00

  • Alaska Airlines AS571: SEA 2026-12-10 13:33:00 → ONT 2026-12-10 16:05:00; nonstop; 152 minutes. Local airport times.
  • Alaska Airlines AS677: ONT 2026-12-12 11:57:00 → SEA 2026-12-12 14:49:00; nonstop; 172 minutes. Local airport times.

2026-12-10 → 2026-12-13 · Axel-exclusive $165.00

  • Frontier Airlines F92276: SEA 2026-12-10 10:50:00 → ONT 2026-12-10 13:38:00; nonstop; 168 minutes. Local airport times.
  • Frontier Airlines F92275: ONT 2026-12-13 06:00:00 → SEA 2026-12-13 09:03:00; nonstop; 183 minutes. Local airport times.

2026-12-10 → 2026-12-13 · Axel-exclusive $279.00

  • Alaska Airlines AS571: SEA 2026-12-10 13:33:00 → ONT 2026-12-10 16:05:00; nonstop; 152 minutes. Local airport times.
  • Alaska Airlines AS677: ONT 2026-12-13 11:57:00 → SEA 2026-12-13 14:49:00; nonstop; 172 minutes. Local airport times.

2026-12-10 → 2026-12-14 · Axel-exclusive $165.00

  • Frontier Airlines F92276: SEA 2026-12-10 10:50:00 → ONT 2026-12-10 13:38:00; nonstop; 168 minutes. Local airport times.
  • Frontier Airlines F92275: ONT 2026-12-14 06:00:00 → SEA 2026-12-14 09:03:00; nonstop; 183 minutes. Local airport times.

2026-12-10 → 2026-12-14 · Axel-exclusive $279.00

  • Alaska Airlines AS571: SEA 2026-12-10 13:33:00 → ONT 2026-12-10 16:05:00; nonstop; 152 minutes. Local airport times.
  • Alaska Airlines AS677: ONT 2026-12-14 11:57:00 → SEA 2026-12-14 14:49:00; nonstop; 172 minutes. Local airport times.

2026-12-10 → 2026-12-16 · Axel-exclusive $165.00

  • Frontier Airlines F92276: SEA 2026-12-10 10:50:00 → ONT 2026-12-10 13:38:00; nonstop; 168 minutes. Local airport times.
  • Frontier Airlines F92275: ONT 2026-12-16 06:00:00 → SEA 2026-12-16 09:03:00; nonstop; 183 minutes. Local airport times.

2026-12-10 → 2026-12-16 · Axel-exclusive $279.00

  • Alaska Airlines AS571: SEA 2026-12-10 13:33:00 → ONT 2026-12-10 16:05:00; nonstop; 152 minutes. Local airport times.
  • Alaska Airlines AS677: ONT 2026-12-16 11:57:00 → SEA 2026-12-16 14:49:00; nonstop; 172 minutes. Local airport times.

2026-12-10 → 2026-12-17 · Axel-exclusive $165.00

  • Frontier Airlines F92276: SEA 2026-12-10 10:50:00 → ONT 2026-12-10 13:38:00; nonstop; 168 minutes. Local airport times.
  • Frontier Airlines F92275: ONT 2026-12-17 06:00:00 → SEA 2026-12-17 09:03:00; nonstop; 183 minutes. Local airport times.

2026-12-10 → 2026-12-17 · Axel-exclusive $279.00

  • Alaska Airlines AS571: SEA 2026-12-10 13:33:00 → ONT 2026-12-10 16:05:00; nonstop; 152 minutes. Local airport times.
  • Alaska Airlines AS677: ONT 2026-12-17 11:57:00 → SEA 2026-12-17 14:49:00; nonstop; 172 minutes. Local airport times.

2026-12-10 → 2026-12-18 · Axel-exclusive $165.00

  • Frontier Airlines F92276: SEA 2026-12-10 10:50:00 → ONT 2026-12-10 13:38:00; nonstop; 168 minutes. Local airport times.
  • Frontier Airlines F92275: ONT 2026-12-18 06:00:00 → SEA 2026-12-18 09:03:00; nonstop; 183 minutes. Local airport times.

2026-12-10 → 2026-12-18 · Axel-exclusive $279.00

  • Alaska Airlines AS571: SEA 2026-12-10 13:33:00 → ONT 2026-12-10 16:05:00; nonstop; 152 minutes. Local airport times.
  • Alaska Airlines AS677: ONT 2026-12-18 11:57:00 → SEA 2026-12-18 14:49:00; nonstop; 172 minutes. Local airport times.

2026-12-10 → 2026-12-20 · Axel-exclusive $198.00

  • Frontier Airlines F92276: SEA 2026-12-10 10:50:00 → ONT 2026-12-10 13:38:00; nonstop; 168 minutes. Local airport times.
  • Frontier Airlines F92275: ONT 2026-12-20 06:00:00 → SEA 2026-12-20 09:03:00; nonstop; 183 minutes. Local airport times.

2026-12-10 → 2026-12-20 · Axel-exclusive $334.80

  • Alaska Airlines AS571: SEA 2026-12-10 13:33:00 → ONT 2026-12-10 16:05:00; nonstop; 152 minutes. Local airport times.
  • Alaska Airlines AS677: ONT 2026-12-20 11:57:00 → SEA 2026-12-20 14:49:00; nonstop; 172 minutes. Local airport times.

2026-12-10 → 2026-12-21 · Axel-exclusive $198.00

  • Frontier Airlines F92276: SEA 2026-12-10 10:50:00 → ONT 2026-12-10 13:38:00; nonstop; 168 minutes. Local airport times.
  • Frontier Airlines F92275: ONT 2026-12-21 06:00:00 → SEA 2026-12-21 09:03:00; nonstop; 183 minutes. Local airport times.

2026-12-10 → 2026-12-21 · Axel-exclusive $334.80

  • Alaska Airlines AS571: SEA 2026-12-10 13:33:00 → ONT 2026-12-10 16:05:00; nonstop; 152 minutes. Local airport times.
  • Alaska Airlines AS677: ONT 2026-12-21 11:57:00 → SEA 2026-12-21 14:49:00; nonstop; 172 minutes. Local airport times.

2026-12-10 → 2026-12-22 · Axel-exclusive $198.00

  • Frontier Airlines F92276: SEA 2026-12-10 10:50:00 → ONT 2026-12-10 13:38:00; nonstop; 168 minutes. Local airport times.
  • Frontier Airlines F92275: ONT 2026-12-22 06:00:00 → SEA 2026-12-22 09:03:00; nonstop; 183 minutes. Local airport times.

2026-12-10 → 2026-12-22 · Axel-exclusive $334.80

  • Alaska Airlines AS571: SEA 2026-12-10 13:33:00 → ONT 2026-12-10 16:05:00; nonstop; 152 minutes. Local airport times.
  • Alaska Airlines AS677: ONT 2026-12-22 11:57:00 → SEA 2026-12-22 14:49:00; nonstop; 172 minutes. Local airport times.

2026-12-10 → 2026-12-24 · Axel-exclusive $198.00

  • Frontier Airlines F92276: SEA 2026-12-10 10:50:00 → ONT 2026-12-10 13:38:00; nonstop; 168 minutes. Local airport times.
  • Frontier Airlines F92275: ONT 2026-12-24 06:00:00 → SEA 2026-12-24 09:03:00; nonstop; 183 minutes. Local airport times.

2026-12-10 → 2026-12-24 · Axel-exclusive $334.80

  • Alaska Airlines AS571: SEA 2026-12-10 13:33:00 → ONT 2026-12-10 16:05:00; nonstop; 152 minutes. Local airport times.
  • Alaska Airlines AS677: ONT 2026-12-24 11:57:00 → SEA 2026-12-24 14:49:00; nonstop; 172 minutes. Local airport times.

Explore this route

For AI assistants

  • This page: Seattle (SEA) to Ontario (ONT) · Dec 10, 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 Seattle 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.