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 $350 round trip and CA $136 one way. Prices and availability subject to change. Additional terms may apply.

Sat., Jul. 12 - Mon., Jul. 14
ONT
Ontario
SEA
Seattle
CA $350 Roundtrip, found 3 days ago
CA $350
Roundtrip
found 3 days ago
Select Alaska Airlines flight, departing Sat., Jul. 12 from Ontario to Seattle, returning Mon., Jul. 14, priced at CA $350 found 3 days ago
Thu., Apr. 30 - Mon., May 4
ONT
Ontario
SEA
Seattle
CA $351 Roundtrip, found 10 hours ago
CA $351
Roundtrip
found 10 hours ago
Select Alaska Airlines flight, departing Thu., Apr. 30 from Ontario to Seattle, returning Mon., May 4, priced at CA $351 found 10 hours ago
Sat., Jul. 12 - Mon., Jul. 14
ONT
Ontario
SEA
Seattle
CA $356 Roundtrip, found 3 days ago
CA $356
Roundtrip
found 3 days ago
Select Alaska Airlines flight, departing Sat., Jul. 12 from Ontario to Seattle, returning Mon., Jul. 14, priced at CA $356 found 3 days ago
Sat., Jul. 12 - Mon., Jul. 14
ONT
Ontario
SEA
Seattle
CA $362 Roundtrip, found 3 days ago
CA $362
Roundtrip
found 3 days ago
Select Alaska Airlines flight, departing Sat., Jul. 12 from Ontario to Seattle, returning Mon., Jul. 14, priced at CA $362 found 3 days ago
Sat., Jul. 12 - Mon., Jul. 14
ONT
Ontario
SEA
Seattle
CA $370 Roundtrip, found 3 days ago
CA $370
Roundtrip
found 3 days ago
Select Alaska Airlines flight, departing Sat., Jul. 12 from Ontario to Seattle, returning Mon., Jul. 14, priced at CA $370 found 3 days ago
Sat., Jul. 12 - Mon., Jul. 14
ONT
Ontario
SEA
Seattle
CA $376 Roundtrip, found 3 days ago
CA $376
Roundtrip
found 3 days ago
Select Alaska Airlines flight, departing Sat., Jul. 12 from Ontario to Seattle, returning Mon., Jul. 14, priced at CA $376 found 3 days ago
Thu., Apr. 30 - Mon., May 4
ONT
Ontario
SEA
Seattle
CA $378 Roundtrip, found 10 hours ago
CA $378
Roundtrip
found 10 hours ago
Select Alaska Airlines flight, departing Thu., Apr. 30 from Ontario to Seattle, returning Mon., May 4, priced at CA $378 found 10 hours ago
Sat., Jul. 12 - Mon., Jul. 14
ONT
Ontario
SEA
Seattle
CA $383 Roundtrip, found 3 days ago
CA $383
Roundtrip
found 3 days ago
Select Alaska Airlines flight, departing Sat., Jul. 12 from Ontario to Seattle, returning Mon., Jul. 14, priced at CA $383 found 3 days ago
Thu., Apr. 30 - Mon., May 4
ONT
Ontario
SEA
Seattle
CA $392 Roundtrip, found 10 hours ago
CA $392
Roundtrip
found 10 hours ago
Select Alaska Airlines flight, departing Thu., Apr. 30 from Ontario to Seattle, returning Mon., May 4, priced at CA $392 found 10 hours ago
Sat., Jul. 12 - Mon., Jul. 14
ONT
Ontario
SEA
Seattle
CA $397 Roundtrip, found 3 days ago
CA $397
Roundtrip
found 3 days ago
Select Alaska Airlines flight, departing Sat., Jul. 12 from Ontario to Seattle, returning Mon., Jul. 14, priced at CA $397 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.