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Flights from Ontario to Seattle
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Flights from Ontario to Seattle Starting at NZD 34

We've found these cheap flights for you. You can book one-way or return flight tickets.

  • One way
  • Round-trip
      • Cheapest nonstop
        ONT10:21
        2h 51m
        Nonstop
        SEA13:12
        Mon, Mar 31|Ontario - Seattle|Frontier Airlines
        NZD 34NZD 63
        46% OFF
        46% OFF
        NZD 63NZD 34

        Choose Frontier Airlines flights from Ontario to Seattle. The one-way direct flight with Frontier Airlines departs from Ontario International Airport on Mon, Mar 31, arriving at Seattle-Tacoma International Airport. One-way Prices start from NZD 34 including taxes and charges.

      • ONT10:21
        2h 51m
        Nonstop
        SEA13:12
        Fri, Mar 14|Ontario - Seattle|Frontier Airlines
        NZD 44NZD 63
        30% OFF
        30% OFF
        NZD 63NZD 44

        Choose Frontier Airlines flights from Ontario to Seattle. The one-way direct flight with Frontier Airlines departs from Ontario International Airport on Fri, Mar 14, arriving at Seattle-Tacoma International Airport. One-way Prices start from NZD 44 including taxes and charges.

      • ONT10:21
        2h 51m
        Nonstop
        SEA13:12
        Thu, Mar 20|Ontario - Seattle|Frontier Airlines
        NZD 45NZD 63
        28% OFF
        28% OFF
        NZD 63NZD 45

        Choose Frontier Airlines flights from Ontario to Seattle. The one-way direct flight with Frontier Airlines departs from Ontario International Airport on Thu, Mar 20, arriving at Seattle-Tacoma International Airport. One-way Prices start from NZD 45 including taxes and charges.

      • ONT10:21
        2h 51m
        Nonstop
        SEA13:12
        Mon, Mar 10|Ontario - Seattle|Frontier Airlines
        NZD 49
        NZD 49

        Choose Frontier Airlines flights from Ontario to Seattle. The one-way direct flight with Frontier Airlines departs from Ontario International Airport on Mon, Mar 10, arriving at Seattle-Tacoma International Airport. One-way Prices start from NZD 49 including taxes and charges.

      • ONT16:29
        3h 3m
        Nonstop
        SEA19:32
        Thu, May 8|Ontario - Seattle|Frontier Airlines
        NZD 51
        NZD 51

        Choose Frontier Airlines flights from Ontario to Seattle. The one-way direct flight with Frontier Airlines departs from Ontario International Airport on Thu, May 8, arriving at Seattle-Tacoma International Airport. One-way Prices start from NZD 51 including taxes and charges.

      • ONT10:21
        2h 51m
        Nonstop
        SEA13:12
        Mon, Mar 17|Ontario - Seattle|Frontier Airlines
        NZD 53
        NZD 53

        Choose Frontier Airlines flights from Ontario to Seattle. The one-way direct flight with Frontier Airlines departs from Ontario International Airport on Mon, Mar 17, arriving at Seattle-Tacoma International Airport. One-way Prices start from NZD 53 including taxes and charges.

      • ONT11:25
        2h 51m
        Nonstop
        SEA14:16
        Fri, Feb 21|Ontario - Seattle|Frontier Airlines
        NZD 58
        NZD 58

        Choose Frontier Airlines flights from Ontario to Seattle. The one-way direct flight with Frontier Airlines departs from Ontario International Airport on Fri, Feb 21, arriving at Seattle-Tacoma International Airport. One-way Prices start from NZD 58 including taxes and charges.

      • ONT10:21
        2h 51m
        Nonstop
        SEA13:12
        Sun, Mar 16|Ontario - Seattle|Frontier Airlines
        NZD 58
        NZD 58

        Choose Frontier Airlines flights from Ontario to Seattle. The one-way direct flight with Frontier Airlines departs from Ontario International Airport on Sun, Mar 16, arriving at Seattle-Tacoma International Airport. One-way Prices start from NZD 58 including taxes and charges.

      • ONT10:21
        2h 51m
        Nonstop
        SEA13:12
        Sun, Mar 23|Ontario - Seattle|Frontier Airlines
        NZD 59
        NZD 59

        Choose Frontier Airlines flights from Ontario to Seattle. The one-way direct flight with Frontier Airlines departs from Ontario International Airport on Sun, Mar 23, arriving at Seattle-Tacoma International Airport. One-way Prices start from NZD 59 including taxes and charges.

      • ONT11:25
        2h 51m
        Nonstop
        SEA14:16
        Fri, Feb 28|Ontario - Seattle|Frontier Airlines
        NZD 59
        NZD 59

        Choose Frontier Airlines flights from Ontario to Seattle. The one-way direct flight with Frontier Airlines departs from Ontario International Airport on Fri, Feb 28, arriving at Seattle-Tacoma International Airport. One-way Prices start from NZD 59 including taxes and charges.

      • ONT01:00 pm
        3h 5m
        Nonstop
        SEA02:00 pm
        Mon, Feb 17|Ontario - Seattle|Frontier Airlines
        Find More Flights
        Find More Flights

Crossed out prices are calculated based on the average price of the corresponding route on Trip.com.

Los Angeles to Seattle flight time & flight schedules

Flight info.
Departure
Arrival
Weekly Schedule

  1. F91500

    Frontier Airlines

    00:59

    ONT

    2.3h

    04:17

    DEN

    SMTWTFS
    Search

  2. F91175

    Frontier Airlines

    09:25

    DEN

    3.1h

    11:31

    SEA

    SMTWTFS

  3. AS1091

    Alaska Airlines

    06:00

    ONT

    2.8h

    Nonstop

    08:46

    SEA

    SMTWTFS
    Search

  4. DL4042

    Delta Air Lines

    07:00

    ONT

    3.0h

    Nonstop

    10:03

    SEA

    SMTWTFS
    Search

  5. F91262

    Frontier Airlines

    12:16

    ONT

    2.3h

    15:35

    DEN

    -MTW-FS
    Search

  6. F91175

    Frontier Airlines

    09:25

    DEN

    3.1h

    11:31

    SEA

    SMTWTFS

  7. F91358

    Frontier Airlines

    14:42

    ONT

    1.2h

    15:53

    LAS

    SMTWTFS
    Search

  8. F92407

    Frontier Airlines

    15:00

    LAS

    3.0h

    18:00

    SEA

    S-TWTFS

  9. AS1119

    Alaska Airlines

    16:29

    ONT

    2.7h

    Nonstop

    19:10

    SEA

    SMTWTFS
    Search

  10. F93164

    Frontier Airlines

    16:29

    ONT

    3.0h

    Nonstop

    19:32

    SEA

    SM-WTFS
    Search

  11. AS1399

    Alaska Airlines

    19:20

    ONT

    2.7h

    Nonstop

    22:00

    SEA

    SMTWTFS
    Search
Find more flights and airlines

Find the best time to fly from Ontario to Seattle

We monitor flight fares to help you find the best deals effortlessly

Displayed prices are calculated based on the cheapest average weekly prices of the corresponding route on Trip.com.

FAQ

  • When are flight tickets from Ontario (ONT) to Seattle (SEA) the cheapest?

    Airlines adjust prices for flights from Ontario to Seattle based on the departure date and time of your selection. By analyzing data from all airlines, we've discovered that on Trip.com, you can find the lowest flight prices on Tuesdays, Wednesdays, and Saturdays.

  • How much do flights from Ontario (ONT) to Seattle (SEA) cost?

    According to Trip.com's data, the lowest price is around NZD 263.

  • What is the transportation method from the main airport to downtown in Seattle?

    • The distance from Seattle-Tacoma International Airport to downtown is about 17 km. It takes about 30 minutes by taxi.

How to find a cheap flight from Ontario to Seattle

Wait until the last minute and flight costs are often sky-high. Plan ahead, book the right way, and your savings can soar. We have loads of saving tips to help you find a cheap flight from Ontario to Seattle. Book your flights at the right time and save more.
1
Book Early
Once prices are gone, they're gone. Lock in deals while you can!
2
Compare Flight Prices
Compare prices on travel agency and airline websites.
3
Look Out for Deals
Check airline and travel agency websites for latest flight deals
4
Check One-way Fares
Buying two cheap one-way flights can sometimes be a better deal than a round-trip.
5
Try Different Dates
Flying during the week, early in the morning, or late at night can help save money.
6
Use the Trip.com App
Save up to £10 per person when booking your flights on Trip.com

Flight Information from Ontario to Seattle

Cheapest nonstop flight priceNZD 34
Cheapest round-trip ticket priceNZD 77
Off-season for travelMarch
Peak season for travelFebruary
Flight distance12,362.98 km
Popular airlineAlaska Airlines

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