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 $404 round trip and CA $133 one way. Prices and availability subject to change. Additional terms may apply.

Mon, May 25 - Mon, May 25
ONT
Ontario
SEA
Seattle
CA $404 Roundtrip, found 5 days ago
CA $404
Roundtrip
found 5 days ago
Select Alaska Airlines flight, departing Mon, May 25 from Ontario to Seattle, returning Mon, May 25, priced at CA $404 found 5 days ago
Mon, May 25 - Mon, May 25
ONT
Ontario
SEA
Seattle
CA $423 Roundtrip, found 5 days ago
CA $423
Roundtrip
found 5 days ago
Select Alaska Airlines flight, departing Mon, May 25 from Ontario to Seattle, returning Mon, May 25, priced at CA $423 found 5 days ago
Mon, May 25 - Mon, May 25
ONT
Ontario
SEA
Seattle
CA $452 Roundtrip, found 5 days ago
CA $452
Roundtrip
found 5 days ago
Select Alaska Airlines flight, departing Mon, May 25 from Ontario to Seattle, returning Mon, May 25, priced at CA $452 found 5 days ago
Mon, May 25 - Mon, May 25
ONT
Ontario
SEA
Seattle
CA $492 Roundtrip, found 5 days ago
CA $492
Roundtrip
found 5 days ago
Select Alaska Airlines flight, departing Mon, May 25 from Ontario to Seattle, returning Mon, May 25, priced at CA $492 found 5 days ago
Mon, May 25 - Mon, May 25
ONT
Ontario
SEA
Seattle
CA $499 Roundtrip, found 5 days ago
CA $499
Roundtrip
found 5 days ago
Select Alaska Airlines flight, departing Mon, May 25 from Ontario to Seattle, returning Mon, May 25, priced at CA $499 found 5 days ago
Mon, May 25 - Mon, May 25
ONT
Ontario
SEA
Seattle
CA $539 Roundtrip, found 5 days ago
CA $539
Roundtrip
found 5 days ago
Select Alaska Airlines flight, departing Mon, May 25 from Ontario to Seattle, returning Mon, May 25, priced at CA $539 found 5 days ago
Sun, Feb 15 - Mon, Feb 16
ONT
Ontario
SEA
Seattle
CA $639 Roundtrip, found 1 day ago
CA $639
Roundtrip
found 1 day ago
Select Alaska Airlines flight, departing Sun, Feb 15 from Ontario to Seattle, returning Mon, Feb 16, priced at CA $639 found 1 day ago
Sun, Feb 15 - Mon, Feb 16
ONT
Ontario
SEA
Seattle
CA $649 Roundtrip, found 1 day ago
CA $649
Roundtrip
found 1 day ago
Select Alaska Airlines flight, departing Sun, Feb 15 from Ontario to Seattle, returning Mon, Feb 16, priced at CA $649 found 1 day ago
Sun, Feb 15 - Mon, Feb 16
ONT
Ontario
SEA
Seattle
CA $728 Roundtrip, found 1 day ago
CA $728
Roundtrip
found 1 day ago
Select Alaska Airlines flight, departing Sun, Feb 15 from Ontario to Seattle, returning Mon, Feb 16, priced at CA $728 found 1 day ago
Sun, Feb 15 - Mon, Feb 16
ONT
Ontario
SEA
Seattle
CA $742 Roundtrip, found 1 day ago
CA $742
Roundtrip
found 1 day ago
Select Alaska Airlines flight, departing Sun, Feb 15 from Ontario to Seattle, returning Mon, Feb 16, priced at CA $742 found 1 day 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.

Popular Flight Routes from Ontario (ONT)

Travelers at ONT love to visit these top cities. Roam to the top destinations from Ontario (ONT) today with the cheap prices from Travelocity!

Popular Flight Routes from Seattle (SEA)

Travelers at SEA love to visit these top cities. Roam to the top destinations from Seattle(SEA) today with the cheap prices from Travelocity!

*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.