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Cheap flight deals from Seattle to Ontario Starting at PHP 1,687

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

  • One way
  • Round-trip
      • Cheapest nonstop
        SEA04:35 pm
        2h 37m
        Nonstop
        ONT07:12 pm
        Thu, Jan 16|Seattle - Ontario|Frontier Airlines
        PHP 1,687PHP 3,325
        49% OFF
        49% OFF
        PHP 3,325PHP 1,687

        Choose Frontier Airlines flights from Seattle to Ontario. The one-way direct flight with Frontier Airlines departs from Seattle-Tacoma International Airport on Thu, Jan 16, arriving at Ontario International Airport. One-way Prices start from PHP 1,687 including taxes and charges.

      • SEA04:35 pm
        2h 37m
        Nonstop
        ONT07:12 pm
        Thu, Jan 30|Seattle - Ontario|Frontier Airlines
        PHP 1,727PHP 3,325
        48% OFF
        48% OFF
        PHP 3,325PHP 1,727

        Choose Frontier Airlines flights from Seattle to Ontario. The one-way direct flight with Frontier Airlines departs from Seattle-Tacoma International Airport on Thu, Jan 30, arriving at Ontario International Airport. One-way Prices start from PHP 1,727 including taxes and charges.

      • SEA01:36 pm
        2h 37m
        Nonstop
        ONT04:13 pm
        Thu, Feb 20|Seattle - Ontario|Frontier Airlines
        PHP 1,911PHP 3,325
        43% OFF
        43% OFF
        PHP 3,325PHP 1,911

        Choose Frontier Airlines flights from Seattle to Ontario. The one-way direct flight with Frontier Airlines departs from Seattle-Tacoma International Airport on Thu, Feb 20, arriving at Ontario International Airport. One-way Prices start from PHP 1,911 including taxes and charges.

      • SEA12:52 pm
        2h 37m
        Nonstop
        ONT03:29 pm
        Fri, Mar 14|Seattle - Ontario|Frontier Airlines
        PHP 1,999
        PHP 1,999

        Choose Frontier Airlines flights from Seattle to Ontario. The one-way direct flight with Frontier Airlines departs from Seattle-Tacoma International Airport on Fri, Mar 14, arriving at Ontario International Airport. One-way Prices start from PHP 1,999 including taxes and charges.

      • SEA12:52 pm
        2h 37m
        Nonstop
        ONT03:29 pm
        Mon, Mar 10|Seattle - Ontario|Frontier Airlines
        PHP 2,311
        PHP 2,311

        Choose Frontier Airlines flights from Seattle to Ontario. The one-way direct flight with Frontier Airlines departs from Seattle-Tacoma International Airport on Mon, Mar 10, arriving at Ontario International Airport. One-way Prices start from PHP 2,311 including taxes and charges.

      • SEA12:52 pm
        2h 37m
        Nonstop
        ONT03:29 pm
        Thu, Mar 13|Seattle - Ontario|Frontier Airlines
        PHP 2,367
        PHP 2,367

        Choose Frontier Airlines flights from Seattle to Ontario. The one-way direct flight with Frontier Airlines departs from Seattle-Tacoma International Airport on Thu, Mar 13, arriving at Ontario International Airport. One-way Prices start from PHP 2,367 including taxes and charges.

      • SEA12:52 pm
        2h 37m
        Nonstop
        ONT03:29 pm
        Mon, Mar 17|Seattle - Ontario|Frontier Airlines
        PHP 2,367
        PHP 2,367

        Choose Frontier Airlines flights from Seattle to Ontario. The one-way direct flight with Frontier Airlines departs from Seattle-Tacoma International Airport on Mon, Mar 17, arriving at Ontario International Airport. One-way Prices start from PHP 2,367 including taxes and charges.

      • SEA12:52 pm
        2h 37m
        Nonstop
        ONT03:29 pm
        Thu, Mar 20|Seattle - Ontario|Frontier Airlines
        PHP 2,383
        PHP 2,383

        Choose Frontier Airlines flights from Seattle to Ontario. The one-way direct flight with Frontier Airlines departs from Seattle-Tacoma International Airport on Thu, Mar 20, arriving at Ontario International Airport. One-way Prices start from PHP 2,383 including taxes and charges.

      • SEA04:35 pm
        2h 37m
        Nonstop
        ONT07:12 pm
        Thu, Jan 23|Seattle - Ontario|Frontier Airlines
        PHP 2,471
        PHP 2,471

        Choose Frontier Airlines flights from Seattle to Ontario. The one-way direct flight with Frontier Airlines departs from Seattle-Tacoma International Airport on Thu, Jan 23, arriving at Ontario International Airport. One-way Prices start from PHP 2,471 including taxes and charges.

      • SEA04:35 pm
        2h 37m
        Nonstop
        ONT07:12 pm
        Sun, Feb 9|Seattle - Ontario|Frontier Airlines
        PHP 2,479
        PHP 2,479

        Choose Frontier Airlines flights from Seattle to Ontario. The one-way direct flight with Frontier Airlines departs from Seattle-Tacoma International Airport on Sun, Feb 9, arriving at Ontario International Airport. One-way Prices start from PHP 2,479 including taxes and charges.

      • SEA01:00 pm
        3h 5m
        Nonstop
        ONT02:00 pm
        Wed, Jan 22|Seattle - Ontario|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.

When is the cheapest time to fly from Seattle to Ontario?

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.

Alternative Cheap Routes from Seattle to Ontario

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

  • Cheapest
    Frontier Airlines
    SEA
    04:35 pm
    2h 37m
    Nonstop
    ONT
    07:12 pm
    Seattle-Tacoma International Airport - Ontario International Airport
    Thu, Jan 16Frontier Airlines
    PHP 1,687
  • Frontier Airlines
    SEA
    04:35 pm
    2h 37m
    Nonstop
    ONT
    07:12 pm
    Seattle-Tacoma International Airport - Ontario International Airport
    Thu, Jan 16Frontier Airlines
    PHP 1,687
    Find More Flights

Frequently Asked Questions

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

    Airlines adjust prices for flights from Seattle to Ontario 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 Seattle (SEA) to Ontario (ONT) cost?

    According to Trip.com's data, the lowest price is around PHP 8,916.

How to find a cheap flight from Seattle to Ontario

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 Seattle to Ontario. 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 Info | Seattle to Ontario

Cheapest nonstop flight pricePHP 1,687
Cheapest round-trip ticket pricePHP 3,374
Off-season for travelApril
Peak season for travelSeptember
Flight distance12,362.98 km
Popular airlineAlaska Airlines

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