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NT$4,443 Cheap Flights from Ontario Intl. Airport (ONT) to Seattle (SEA)

Photo by Port of Seattle
Open Photo by Port of Seattle

Cheap Flights from Ontario to Seattle (ONT-SEA)

Prices were available within the past 7 days and start at NT$4,443 for one-way flights and NT$6,967 for roundtrip, for the period specified. Prices and availability are subject to change.
Delta
Tue, Sep 1 - Tue, Sep 15
ONT
Ontario
SEA
Seattle
NT$6,967
Roundtrip
Found 2 days ago
Select Delta flight, departing Tue, Sep 1 from Ontario to Seattle, returning Tue, Sep 15, priced at NT$6,967 Found 2 days ago
Delta
Sun, Aug 23 - Wed, Sep 9
ONT
Ontario
SEA
Seattle
NT$7,602
Roundtrip
Found 1 day ago
Select Delta flight, departing Sun, Aug 23 from Ontario to Seattle, returning Wed, Sep 9, priced at NT$7,602 Found 1 day ago
Delta
Tue, Sep 1 - Tue, Sep 15
ONT
Ontario
SEA
Seattle
NT$8,573
Roundtrip
Found 2 days ago
Select Delta flight, departing Tue, Sep 1 from Ontario to Seattle, returning Tue, Sep 15, priced at NT$8,573 Found 2 days ago
Delta
Tue, Sep 1 - Tue, Sep 15
ONT
Ontario
SEA
Seattle
NT$8,889
Roundtrip
Found 2 days ago
Select Delta flight, departing Tue, Sep 1 from Ontario to Seattle, returning Tue, Sep 15, priced at NT$8,889 Found 2 days ago
Delta
Tue, Sep 1 - Tue, Sep 15
ONT
Ontario
SEA
Seattle
NT$9,387
Roundtrip
Found 2 days ago
Select Delta flight, departing Tue, Sep 1 from Ontario to Seattle, returning Tue, Sep 15, priced at NT$9,387 Found 2 days ago
Delta
Tue, Sep 1 - Tue, Sep 15
ONT
Ontario
SEA
Seattle
NT$9,532
Roundtrip
Found 2 days ago
Select Delta flight, departing Tue, Sep 1 from Ontario to Seattle, returning Tue, Sep 15, priced at NT$9,532 Found 2 days ago
United
Tue, Sep 1 - Tue, Sep 15
ONT
Ontario
SEA
Seattle
NT$10,024
Roundtrip
Found 2 days ago
Select United flight, departing Tue, Sep 1 from Ontario to Seattle, returning Tue, Sep 15, priced at NT$10,024 Found 2 days ago
American Airlines
Tue, Sep 1 - Tue, Sep 15
ONT
Ontario
SEA
Seattle
NT$10,169
Roundtrip
Found 2 days ago
Select American Airlines flight, departing Tue, Sep 1 from Ontario to Seattle, returning Tue, Sep 15, priced at NT$10,169 Found 2 days ago
United
Tue, Sep 1 - Tue, Sep 15
ONT
Ontario
SEA
Seattle
NT$10,174
Roundtrip
Found 2 days ago
Select United flight, departing Tue, Sep 1 from Ontario to Seattle, returning Tue, Sep 15, priced at NT$10,174 Found 2 days ago
Alaska Airlines
Sat, Jul 25 - Sat, Aug 1
ONT
Ontario
SEA
Seattle
NT$13,532
Roundtrip
Found 1 day ago
Select Alaska Airlines flight, departing Sat, Jul 25 from Ontario to Seattle, returning Sat, Aug 1, priced at NT$13,532 Found 1 day ago

Alternative airports near Seattle

Prices were available within the past 7 days. Prices and availability are subject to change.

Select flight to Seattle - Tacoma Intl. SEA. Cheapest option available. Average driving time to city center is 20 minutes. Flights from NT$12,255
SEA
Seattle - Tacoma Intl.
Cheapest
Average driving time to city center20 min
Flights from NT$12,255

Find the cheapest month to fly from Ontario (ONT) to Seattle (SEA)

April is typically the cheapest month to fly

From NT$3,156 - NT$6,279 per traveler.

Travel information

Origin airport
Ontario Intl. Airport
Destination airport
Seattle-Tacoma International Airport
Distance
1,539 km away
Airlines serving
Frontier Airlines, Alaska Airlines, Delta, Southwest Airlines, United, American Airlines, JetBlue Airways
Popular airline
Frontier Airlines
Roundtrip price
NT$6,967
Average flight time
2 hours 50 mins
*Available to One Key members.