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Ontario International Airport to Seattle flight
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Cheap Flights from Ontario International Airport to Seattle

Search for flights from Ontario International Airport to Seattle and check out affordable one-way and round-trip options.

  • One way
  • Round-trip
      • Cheapest nonstop
        ONT10:03 AM
        2h 50m
        Nonstop
        SEA12:53 PM
        Ontario - Seattle|Sat, Jul 5|Frontier Airlines
        $47$79
        41% OFF
        41% OFF
        $79$47

        Choose Frontier Airlines flights from Ontario to Seattle. The one-way direct flight with Frontier Airlines departs from Ontario International Airport on Sat, Jul 5, arriving at Seattle Tacoma Intl. Airport. One-way Prices start from $47 including taxes and charges.

      • ONT10:03 AM
        2h 46m
        Nonstop
        SEA12:49 PM
        Ontario - Seattle|Sat, Jun 28|Frontier Airlines
        $49$79
        38% OFF
        38% OFF
        $79$49

        Choose Frontier Airlines flights from Ontario to Seattle. The one-way direct flight with Frontier Airlines departs from Ontario International Airport on Sat, Jun 28, arriving at Seattle Tacoma Intl. Airport. One-way Prices start from $49 including taxes and charges.

      • ONT5:03 PM
        2h 54m
        Nonstop
        SEA7:57 PM
        Ontario - Seattle|Wed, Aug 27|Frontier Airlines
        $60$79
        24% OFF
        24% OFF
        $79$60

        Choose Frontier Airlines flights from Ontario to Seattle. The one-way direct flight with Frontier Airlines departs from Ontario International Airport on Wed, Aug 27, arriving at Seattle Tacoma Intl. Airport. One-way Prices start from $60 including taxes and charges.

      • ONT10:03 AM
        2h 50m
        Nonstop
        SEA12:53 PM
        Ontario - Seattle|Sat, Jul 19|Frontier Airlines
        $60
        $60

        Choose Frontier Airlines flights from Ontario to Seattle. The one-way direct flight with Frontier Airlines departs from Ontario International Airport on Sat, Jul 19, arriving at Seattle Tacoma Intl. Airport. One-way Prices start from $60 including taxes and charges.

      • ONT10:03 AM
        2h 50m
        Nonstop
        SEA12:53 PM
        Ontario - Seattle|Tue, Jul 15|Frontier Airlines
        $61
        $61

        Choose Frontier Airlines flights from Ontario to Seattle. The one-way direct flight with Frontier Airlines departs from Ontario International Airport on Tue, Jul 15, arriving at Seattle Tacoma Intl. Airport. One-way Prices start from $61 including taxes and charges.

      • ONT10:03 AM
        2h 50m
        Nonstop
        SEA12:53 PM
        Ontario - Seattle|Sat, Aug 9|Frontier Airlines
        $61
        $61

        Choose Frontier Airlines flights from Ontario to Seattle. The one-way direct flight with Frontier Airlines departs from Ontario International Airport on Sat, Aug 9, arriving at Seattle Tacoma Intl. Airport. One-way Prices start from $61 including taxes and charges.

      • ONT10:03 AM
        2h 50m
        Nonstop
        SEA12:53 PM
        Ontario - Seattle|Sat, Jul 12|Frontier Airlines
        $62
        $62

        Choose Frontier Airlines flights from Ontario to Seattle. The one-way direct flight with Frontier Airlines departs from Ontario International Airport on Sat, Jul 12, arriving at Seattle Tacoma Intl. Airport. One-way Prices start from $62 including taxes and charges.

      • ONT10:03 AM
        2h 50m
        Nonstop
        SEA12:53 PM
        Ontario - Seattle|Tue, Jul 8|Frontier Airlines
        $64
        $64

        Choose Frontier Airlines flights from Ontario to Seattle. The one-way direct flight with Frontier Airlines departs from Ontario International Airport on Tue, Jul 8, arriving at Seattle Tacoma Intl. Airport. One-way Prices start from $64 including taxes and charges.

      • ONT10:03 AM
        2h 46m
        Nonstop
        SEA12:49 PM
        Ontario - Seattle|Tue, Jul 1|Frontier Airlines
        $69
        $69

        Choose Frontier Airlines flights from Ontario to Seattle. The one-way direct flight with Frontier Airlines departs from Ontario International Airport on Tue, Jul 1, arriving at Seattle Tacoma Intl. Airport. One-way Prices start from $69 including taxes and charges.

      • ONT4:56 PM
        2h 57m
        Nonstop
        SEA7:53 PM
        Ontario - Seattle|Sat, Aug 30|Frontier Airlines
        $69
        $69

        Choose Frontier Airlines flights from Ontario to Seattle. The one-way direct flight with Frontier Airlines departs from Ontario International Airport on Sat, Aug 30, arriving at Seattle Tacoma Intl. Airport. One-way Prices start from $69 including taxes and charges.

      • ONT1:00 PM
        3h 5m
        Nonstop
        SEA2:00 PM
        Los Angeles - Seattle|Mon, Jun 30|Frontier Airlines
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        Find More Flights

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

Selected Airlines from Ontario International Airport to Seattle

See which airlines fly from Ontario International Airport to Seattle. Find the airline that best meets your travel needs by comparing prices and treat yourself to an enjoyable journey.
Alaska Airlines logoAlaska AirlinesFrontier Airlines logoFrontier AirlinesDelta Air Lines logoDelta Air LinesHawaiian Airlines logoHawaiian AirlinesUnited Airlines logoUnited AirlinesSpirit Airlines logoSpirit AirlinesAmerican Airlines logoAmerican Airlines

Flight Info of Flights from Ontario International Airport to Seattle

Cheapest round-trip ticket price$108
Cheapest one-way flight price$61
Off-season for travelApril
Peak season for travelMarch

FAQs for Ontario International Airport to Seattle Flights

  • 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.

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