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Flights from Ontario to Seattle
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Flights from Ontario to Seattle Starting at NZD 33

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

  • One way
  • Round-trip
      • Cheapest nonstop
        ONT11:27
        2h 51m
        Nonstop
        SEA14:18
        Thu, Feb 6|Ontario - Seattle|Frontier Airlines
        NZD 33NZD 86
        61% OFF
        61% OFF
        NZD 86NZD 33

        Choose Frontier Airlines flights from Ontario to Seattle. The one-way direct flight with Frontier Airlines departs from Ontario International Airport on Thu, Feb 6, arriving at Seattle-Tacoma International Airport. One-way Prices start from NZD 33 including taxes and charges.

      • ONT11:26
        2h 59m
        Nonstop
        SEA14:25
        Thu, Jan 9|Ontario - Seattle|Frontier Airlines
        NZD 35NZD 86
        59% OFF
        59% OFF
        NZD 86NZD 35

        Choose Frontier Airlines flights from Ontario to Seattle. The one-way direct flight with Frontier Airlines departs from Ontario International Airport on Thu, Jan 9, arriving at Seattle-Tacoma International Airport. One-way Prices start from NZD 35 including taxes and charges.

      • ONT11:27
        2h 51m
        Nonstop
        SEA14:18
        Thu, Jan 16|Ontario - Seattle|Frontier Airlines
        NZD 51NZD 86
        40% OFF
        40% OFF
        NZD 86NZD 51

        Choose Frontier Airlines flights from Ontario to Seattle. The one-way direct flight with Frontier Airlines departs from Ontario International Airport on Thu, Jan 16, arriving at Seattle-Tacoma International Airport. One-way Prices start from NZD 51 including taxes and charges.

      • ONT11:27
        2h 51m
        Nonstop
        SEA14:18
        Thu, Jan 23|Ontario - Seattle|Frontier Airlines
        NZD 56
        NZD 56

        Choose Frontier Airlines flights from Ontario to Seattle. The one-way direct flight with Frontier Airlines departs from Ontario International Airport on Thu, Jan 23, arriving at Seattle-Tacoma International Airport. One-way Prices start from NZD 56 including taxes and charges.

      • ONT11:33
        2h 51m
        Nonstop
        SEA14:24
        Mon, Feb 10|Ontario - Seattle|Alaska Airlines
        NZD 73
        NZD 73

        Choose Alaska Airlines flights from Ontario to Seattle. The one-way direct flight with Alaska Airlines departs from Ontario International Airport on Mon, Feb 10, arriving at Seattle-Tacoma International Airport. One-way Prices start from NZD 73 including taxes and charges.

      • ONT06:00
        2h 54m
        Nonstop
        SEA08:54
        Mon, Feb 3|Ontario - Seattle|Alaska Airlines
        NZD 73
        NZD 73

        Choose Alaska Airlines flights from Ontario to Seattle. The one-way direct flight with Alaska Airlines departs from Ontario International Airport on Mon, Feb 3, arriving at Seattle-Tacoma International Airport. One-way Prices start from NZD 73 including taxes and charges.

      • ONT06:00
        2h 54m
        Nonstop
        SEA08:54
        Thu, Feb 6|Ontario - Seattle|Alaska Airlines
        NZD 73
        NZD 73

        Choose Alaska Airlines flights from Ontario to Seattle. The one-way direct flight with Alaska Airlines departs from Ontario International Airport on Thu, Feb 6, arriving at Seattle-Tacoma International Airport. One-way Prices start from NZD 73 including taxes and charges.

      • ONT10:21
        2h 51m
        Nonstop
        SEA13:12
        Thu, Mar 13|Ontario - Seattle|Frontier Airlines
        NZD 73
        NZD 73

        Choose Frontier Airlines flights from Ontario to Seattle. The one-way direct flight with Frontier Airlines departs from Ontario International Airport on Thu, Mar 13, arriving at Seattle-Tacoma International Airport. One-way Prices start from NZD 73 including taxes and charges.

      • ONT10:21
        2h 51m
        Nonstop
        SEA13:12
        Mon, Mar 17|Ontario - Seattle|Frontier Airlines
        NZD 73
        NZD 73

        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 73 including taxes and charges.

      • ONT10:21
        2h 51m
        Nonstop
        SEA13:12
        Thu, Mar 27|Ontario - Seattle|Frontier Airlines
        NZD 74
        NZD 74

        Choose Frontier Airlines flights from Ontario to Seattle. The one-way direct flight with Frontier Airlines departs from Ontario International Airport on Thu, Mar 27, arriving at Seattle-Tacoma International Airport. One-way Prices start from NZD 74 including taxes and charges.

      • ONT01:00 pm
        3h 5m
        Nonstop
        SEA02:00 pm
        Sun, Jan 12|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.

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.

Airlines Flying from Ontario to Seattle

Compare prices, find the option that best suits your travel needs, and enjoy a comfortable journey with a trusted airline.

Frontier Airlines
From NZD 33
Alaska Airlines
From NZD 73
Delta Air Lines
From NZD 77
United Airlines
From NZD 178
American Airlines
From NZD 179
Southwest Airlines
From NZD 211

Find more flights and airlines

Alternative Routes from Ontario to Seattle

Searching for potential routes that might be cheaper and faster? Check out these alternative flights from Ontario to Seattle.

  • Cheapest
    Frontier Airlines
    ONT
    11:27
    2h 51m
    Nonstop
    SEA
    14:18
    Ontario International Airport - Seattle-Tacoma International Airport
    Thu, Feb 6Frontier Airlines
    NZD 33
  • Frontier Airlines
    ONT
    11:27
    2h 51m
    Nonstop
    SEA
    14:18
    Ontario International Airport - Seattle-Tacoma International Airport
    Thu, Feb 6Frontier Airlines
    NZD 33
    Find More Flights

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 265.

  • 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.
    • The distance from Lake Union Sea Plane Base to downtown is about 2 km. It takes about 20 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 33
Cheapest round-trip ticket priceNZD 69
Off-season for travelMarch
Peak season for travelFebruary
Flight distance12,362.98 km
Popular airlineAlaska Airlines

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