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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$6,977 for roundtrip, for the period specified. Prices and availability are subject to change.
Delta
Sat, Oct 17 - Sat, Oct 24
ONT
Ontario
SEA
Seattle
NT$6,977
Roundtrip
Found 6 hours ago
Select Delta flight, departing Sat, Oct 17 from Ontario to Seattle, returning Sat, Oct 24, priced at NT$6,977 Found 6 hours ago
Delta
Sun, Aug 23 - Wed, Sep 9
ONT
Ontario
SEA
Seattle
NT$7,602
Roundtrip
Found 2 days ago
Select Delta flight, departing Sun, Aug 23 from Ontario to Seattle, returning Wed, Sep 9, priced at NT$7,602 Found 2 days ago
Delta
Fri, Nov 13 - Sun, Nov 15
ONT
Ontario
SEA
Seattle
NT$8,264
Roundtrip
Found 11 hours ago
Select Delta flight, departing Fri, Nov 13 from Ontario to Seattle, returning Sun, Nov 15, priced at NT$8,264 Found 11 hours ago
Delta
Sat, Oct 17 - Sat, Oct 24
ONT
Ontario
SEA
Seattle
NT$8,585
Roundtrip
Found 6 hours ago
Select Delta flight, departing Sat, Oct 17 from Ontario to Seattle, returning Sat, Oct 24, priced at NT$8,585 Found 6 hours ago
Delta
Sat, Oct 17 - Sat, Oct 24
ONT
Ontario
SEA
Seattle
NT$8,901
Roundtrip
Found 6 hours ago
Select Delta flight, departing Sat, Oct 17 from Ontario to Seattle, returning Sat, Oct 24, priced at NT$8,901 Found 6 hours ago
Delta
Fri, Nov 13 - Sun, Nov 15
ONT
Ontario
SEA
Seattle
NT$9,544
Roundtrip
Found 11 hours ago
Select Delta flight, departing Fri, Nov 13 from Ontario to Seattle, returning Sun, Nov 15, priced at NT$9,544 Found 11 hours ago
United
Sat, Oct 17 - Sat, Oct 24
ONT
Ontario
SEA
Seattle
NT$9,545
Roundtrip
Found 6 hours ago
Select United flight, departing Sat, Oct 17 from Ontario to Seattle, returning Sat, Oct 24, priced at NT$9,545 Found 6 hours ago
Delta
Tue, Sep 1 - Tue, Sep 15
ONT
Ontario
SEA
Seattle
NT$9,550
Roundtrip
Found 15 hours ago
Select Delta flight, departing Tue, Sep 1 from Ontario to Seattle, returning Tue, Sep 15, priced at NT$9,550 Found 15 hours ago
American Airlines
Sat, Oct 17 - Sat, Oct 24
ONT
Ontario
SEA
Seattle
NT$10,182
Roundtrip
Found 6 hours ago
Select American Airlines flight, departing Sat, Oct 17 from Ontario to Seattle, returning Sat, Oct 24, priced at NT$10,182 Found 6 hours ago
Alaska Airlines
Sat, Jul 25 - Sat, Aug 1
ONT
Ontario
SEA
Seattle
NT$13,532
Roundtrip
Found 2 days ago
Select Alaska Airlines flight, departing Sat, Jul 25 from Ontario to Seattle, returning Sat, Aug 1, priced at NT$13,532 Found 2 days 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$14,181
SEA
Seattle - Tacoma Intl.
Cheapest
Average driving time to city center20 min
Flights from NT$14,181

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, United, Southwest Airlines, American Airlines, JetBlue Airways
Popular airline
Frontier Airlines
Roundtrip price
NT$6,977
Average flight time
2 hours 52 mins
*Available to One Key members.