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 $164 round trip and CA $277 one way. Prices and availability subject to change. Additional terms may apply.

Thu, Jan 29 - Wed, Feb 4
ONT
Ontario
SEA
Seattle
CA $164 Roundtrip, found 5 days ago
CA $164
Roundtrip
found 5 days ago
Select Alaska Airlines flight, departing Thu, Jan 29 from Ontario to Seattle, returning Wed, Feb 4, priced at CA $164 found 5 days ago
Thu, Jan 29 - Wed, Feb 4
ONT
Ontario
SEA
Seattle
CA $168 Roundtrip, found 5 days ago
CA $168
Roundtrip
found 5 days ago
Select Alaska Airlines flight, departing Thu, Jan 29 from Ontario to Seattle, returning Wed, Feb 4, priced at CA $168 found 5 days ago
Thu, Jan 29 - Wed, Feb 4
ONT
Ontario
SEA
Seattle
CA $217 Roundtrip, found 5 days ago
CA $217
Roundtrip
found 5 days ago
Select Alaska Airlines flight, departing Thu, Jan 29 from Ontario to Seattle, returning Wed, Feb 4, priced at CA $217 found 5 days ago
Thu, Jan 29 - Wed, Feb 4
ONT
Ontario
SEA
Seattle
CA $222 Roundtrip, found 5 days ago
CA $222
Roundtrip
found 5 days ago
Select Alaska Airlines flight, departing Thu, Jan 29 from Ontario to Seattle, returning Wed, Feb 4, priced at CA $222 found 5 days ago
Thu, Jan 29 - Wed, Feb 4
ONT
Ontario
SEA
Seattle
CA $228 Roundtrip, found 5 days ago
CA $228
Roundtrip
found 5 days ago
Select Alaska Airlines flight, departing Thu, Jan 29 from Ontario to Seattle, returning Wed, Feb 4, priced at CA $228 found 5 days ago
Thu, Jan 29 - Wed, Feb 4
ONT
Ontario
SEA
Seattle
CA $231 Roundtrip, found 5 days ago
CA $231
Roundtrip
found 5 days ago
Select Alaska Airlines flight, departing Thu, Jan 29 from Ontario to Seattle, returning Wed, Feb 4, priced at CA $231 found 5 days ago
Thu, Jan 29 - Wed, Feb 4
ONT
Ontario
SEA
Seattle
CA $285 Roundtrip, found 5 days ago
CA $285
Roundtrip
found 5 days ago
Select Alaska Airlines flight, departing Thu, Jan 29 from Ontario to Seattle, returning Wed, Feb 4, priced at CA $285 found 5 days ago
Thu, Jan 29 - Wed, Feb 4
ONT
Ontario
SEA
Seattle
CA $311 Roundtrip, found 5 days ago
CA $311
Roundtrip
found 5 days ago
Select Alaska Airlines flight, departing Thu, Jan 29 from Ontario to Seattle, returning Wed, Feb 4, priced at CA $311 found 5 days ago
Thu, Jan 29 - Wed, Feb 4
ONT
Ontario
SEA
Seattle
CA $341 Roundtrip, found 5 days ago
CA $341
Roundtrip
found 5 days ago
Select Alaska Airlines flight, departing Thu, Jan 29 from Ontario to Seattle, returning Wed, Feb 4, priced at CA $341 found 5 days ago
Thu, Jan 29 - Wed, Feb 4
ONT
Ontario
SEA
Seattle
CA $343 Roundtrip, found 5 days ago
CA $343
Roundtrip
found 5 days ago
Select Alaska Airlines flight, departing Thu, Jan 29 from Ontario to Seattle, returning Wed, Feb 4, priced at CA $343 found 5 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.