Cheap Flights From Seattle - Tacoma Intl. (SEA) To Ontario Intl. Airport (ONT)

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Cheapest Flights from Seattle (SEA) to Ontario Intl. Airport (ONT)

The cheapest flights to Ontario Intl. Airport found within the past 7 days were CA $306 round trip and CA $174 one way. Prices and availability subject to change. Additional terms may apply.

Thu, Aug 20 - Wed, Aug 26
SEA
Seattle
ONT
Ontario
CA $306 Roundtrip, found 1 day ago
CA $306
Roundtrip
found 1 day ago
Select Alaska Airlines flight, departing Thu, Aug 20 from Seattle to Ontario, returning Wed, Aug 26, priced at CA $306 found 1 day ago
Fri, Aug 28 - Sat, Aug 29
SEA
Seattle
ONT
Ontario
CA $310 Roundtrip, found 21 hours ago
CA $310
Roundtrip
found 21 hours ago
Select Delta flight, departing Fri, Aug 28 from Seattle to Ontario, returning Sat, Aug 29, priced at CA $310 found 21 hours ago
Fri, Aug 21 - Mon, Aug 24
SEA
Seattle
ONT
Ontario
CA $320 Roundtrip, found 2 days ago
CA $320
Roundtrip
found 2 days ago
Select Alaska Airlines flight, departing Fri, Aug 21 from Seattle to Ontario, returning Mon, Aug 24, priced at CA $320 found 2 days ago
Tue, Aug 25 - Sat, Aug 29
SEA
Seattle
ONT
Ontario
CA $324 Roundtrip, found 23 hours ago
CA $324
Roundtrip
found 23 hours ago
Select Alaska Airlines flight, departing Tue, Aug 25 from Seattle to Ontario, returning Sat, Aug 29, priced at CA $324 found 23 hours ago
Sat, Aug 29 - Sat, Sep 12
SEA
Seattle
ONT
Ontario
CA $331 Roundtrip, found 1 day ago
CA $331
Roundtrip
found 1 day ago
Select Alaska Airlines flight, departing Sat, Aug 29 from Seattle to Ontario, returning Sat, Sep 12, priced at CA $331 found 1 day ago
Wed, Oct 14 - Sat, Oct 17
SEA
Seattle
ONT
Ontario
CA $334 Roundtrip, found 1 day ago
CA $334
Roundtrip
found 1 day ago
Select Alaska Airlines flight, departing Wed, Oct 14 from Seattle to Ontario, returning Sat, Oct 17, priced at CA $334 found 1 day ago
Wed, Nov 11 - Wed, Nov 11
SEA
Seattle
ONT
Ontario
CA $338 Roundtrip, found 6 days ago
CA $338
Roundtrip
found 6 days ago
Select Alaska Airlines flight, departing Wed, Nov 11 from Seattle to Ontario, returning Wed, Nov 11, priced at CA $338 found 6 days ago
Sat, Sep 19 - Mon, Sep 21
SEA
Seattle
ONT
Ontario
CA $345 Roundtrip, found 2 days ago
CA $345
Roundtrip
found 2 days ago
Select Alaska Airlines flight, departing Sat, Sep 19 from Seattle to Ontario, returning Mon, Sep 21, priced at CA $345 found 2 days ago
Sat, Oct 31 - Sat, Nov 7
SEA
Seattle
ONT
Ontario
CA $346 Roundtrip, found 6 days ago
CA $346
Roundtrip
found 6 days ago
Select Alaska Airlines flight, departing Sat, Oct 31 from Seattle to Ontario, returning Sat, Nov 7, priced at CA $346 found 6 days ago
Fri, Aug 21 - Mon, Aug 24
SEA
Seattle
ONT
Ontario
CA $348 Roundtrip, found 9 hours ago
CA $348
Roundtrip
found 9 hours ago
Select Alaska Airlines flight, departing Fri, Aug 21 from Seattle to Ontario, returning Mon, Aug 24, priced at CA $348 found 9 hours ago

Frequently asked questions

Are there direct flights from Sea-Tac Airport to Ontario Airport?
If you'd love to travel from Seattle - Tacoma Intl. Airport (SEA) to Los Angeles - Ontario Intl. Airport (ONT) as quickly as possible, you'll be happy to know multiple airlines operate direct flights. Choose your favorite seat with Alaska Airlines or Delta.
What airlines fly from Sea-Tac Airport to Los Angeles - Ontario Intl. Airport (ONT)?
If you're planning a trip to Ontario from Seattle, there are a few airlines offering direct flights. One of the top carriers is Alaska Airlines (AS), which operates 108 flights every month. You'll want to also check out the deals available through Delta (DL). Another popular airline, it operates 91 flights every month on the Seattle to Ontario route. Be sure to compare the two airlines to find your perfect fare.
What is the best day to buy a plane ticket?
Airfares offered on Friday tend to be the cheapest, according to flight demand on Travelocity.ca in 2021. Purchasing your airfares on a Thursday or Saturday can also provide better value, however our advice if you're looking to save money is to avoid booking on a Wednesday or Sunday. Our data shows that those two days have the highest ticket values on average, so keep this in mind if you're browsing flight deals.
What are the cheapest days to fly?
Frequent travellers may already know this, but earlier in the week is often the cheapest time to fly. Flights departing on a Monday are the cheapest of the week. Since flights towards the middle of the week tend to be more popular, this causes the prices to rise. This is why, on average, airfares booked on Travelocity.ca in 2021 were most expensive for Wednesday departures.
How far in advance can you book a flight?
Here's the deal: It is typically possible to start comparing international airfares on Travelocity.ca up to 12 months in advance. However, it does depend on the carrier as not all airlines release their prices that far out. According to our 2021 flight demand trends, last minute planners can still bag a bargain with some of the cheapest fares appearing 2-4 weeks prior to their travel dates.*According to flight demand on Travelocity.ca from January to December 2021. Savings are subject to change and may vary depending on selections made.

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*Price based on the lowest price found within past 24 hours and based upon one night stay for two adults over the next thirty days. Prices and availability subject to change. Additional terms may apply.