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

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Cheapest Flights from Ontario (ONT) to Seattle (SEA)

The cheapest flights to Seattle - Tacoma Intl. found within the past 7 days were CA $293 round trip and CA $98 one way. Prices and availability subject to change. Additional terms may apply.

Thu, Jan 8 - Sun, Jan 11
ONT
Ontario
SEA
Seattle
CA $293 Roundtrip, found 3 days ago
CA $293
Roundtrip
found 3 days ago
Select Alaska Airlines flight, departing Thu, Jan 8 from Ontario to Seattle, returning Sun, Jan 11, priced at CA $293 found 3 days ago
Thu, Jan 8 - Sun, Jan 11
ONT
Ontario
SEA
Seattle
CA $307 Roundtrip, found 3 days ago
CA $307
Roundtrip
found 3 days ago
Select Alaska Airlines flight, departing Thu, Jan 8 from Ontario to Seattle, returning Sun, Jan 11, priced at CA $307 found 3 days ago
Thu, Jan 8 - Sun, Jan 11
ONT
Ontario
SEA
Seattle
CA $309 Roundtrip, found 3 days ago
CA $309
Roundtrip
found 3 days ago
Select Alaska Airlines flight, departing Thu, Jan 8 from Ontario to Seattle, returning Sun, Jan 11, priced at CA $309 found 3 days ago
Thu, Jan 8 - Sun, Jan 11
ONT
Ontario
SEA
Seattle
CA $334 Roundtrip, found 3 days ago
CA $334
Roundtrip
found 3 days ago
Select Alaska Airlines flight, departing Thu, Jan 8 from Ontario to Seattle, returning Sun, Jan 11, priced at CA $334 found 3 days ago
Thu, Jan 8 - Sun, Jan 11
ONT
Ontario
SEA
Seattle
CA $350 Roundtrip, found 3 days ago
CA $350
Roundtrip
found 3 days ago
Select Alaska Airlines flight, departing Thu, Jan 8 from Ontario to Seattle, returning Sun, Jan 11, priced at CA $350 found 3 days ago
Thu, Jan 8 - Sun, Jan 11
ONT
Ontario
SEA
Seattle
CA $398 Roundtrip, found 3 days ago
CA $398
Roundtrip
found 3 days ago
Select Alaska Airlines flight, departing Thu, Jan 8 from Ontario to Seattle, returning Sun, Jan 11, priced at CA $398 found 3 days ago
Thu, Jan 8 - Sun, Jan 11
ONT
Ontario
SEA
Seattle
CA $427 Roundtrip, found 3 days ago
CA $427
Roundtrip
found 3 days ago
Select Alaska Airlines flight, departing Thu, Jan 8 from Ontario to Seattle, returning Sun, Jan 11, priced at CA $427 found 3 days ago
Thu, Jan 8 - Sun, Jan 11
ONT
Ontario
SEA
Seattle
CA $436 Roundtrip, found 3 days ago
CA $436
Roundtrip
found 3 days ago
Select Alaska Airlines flight, departing Thu, Jan 8 from Ontario to Seattle, returning Sun, Jan 11, priced at CA $436 found 3 days ago
Thu, Jan 8 - Sun, Jan 11
ONT
Ontario
SEA
Seattle
CA $468 Roundtrip, found 3 days ago
CA $468
Roundtrip
found 3 days ago
Select Alaska Airlines flight, departing Thu, Jan 8 from Ontario to Seattle, returning Sun, Jan 11, priced at CA $468 found 3 days ago
Thu, Jan 8 - Sun, Jan 11
ONT
Ontario
SEA
Seattle
CA $478 Roundtrip, found 3 days ago
CA $478
Roundtrip
found 3 days ago
Select Alaska Airlines flight, departing Thu, Jan 8 from Ontario to Seattle, returning Sun, Jan 11, priced at CA $478 found 3 days ago

Frequently asked questions

Are there direct flights from ONT to Sea-Tac Airport?
Multiple airlines offer direct flights from Los Angeles - Ontario Intl. Airport (ONT) to SEA. These include Alaska Airlines and Delta — start with them if you want to touch down at Seattle sooner rather than later.
What airlines fly from Ontario Airport to SEA?
If you need to get to Seattle from Ontario, there are a number of airlines with direct flights. One of the most popular is Alaska Airlines (AS), which offers 108 flights on this route each month. An alternative is Delta (DL), which offers 91 flights every month. The more air carriers you consider, the more likely you are to snap up a sensational deal.
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.
*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.