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Cheap flights from Ontario (ONT) to Seattle (BFI)

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How to find the cheapest flight from Ontario (ONT) to Seattle (BFI)

How to find the cheapest flight from Ontario (ONT) to Seattle (BFI)
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How to find the cheapest flight from Ontario (ONT) to Seattle (BFI)
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How to find the cheapest flight from Ontario (ONT) to Seattle (BFI)
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Cheap flights from Ontario to Seattle in November , December 2026

24 Nov - 13 Dec $ 627.00
ONT
Ontario
Frontier Airlines
1 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
ONT
Ontario
Pick dates
24 Nov - 07 Dec $ 627.00
ONT
Ontario
Frontier Airlines
1 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
ONT
Ontario
Pick dates
24 Nov - 14 Dec $ 634.00
ONT
Ontario
Frontier Airlines
1 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
ONT
Ontario
Pick dates

Last minute flights from Ontario to Seattle

24 Nov - 30 Nov $ 825.00
ONT
Ontario
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
ONT
Ontario
Pick dates
24 Nov - 30 Nov $ 916.00
ONT
Ontario
Frontier Airlines
1 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
ONT
Ontario
Pick dates
24 Nov - 30 Nov $ 960.00
ONT
Ontario
Frontier Airlines
1 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
ONT
Ontario
Pick dates

One-way flights to Seattle from Ontario

10:40 PM - 9:25 PM
Air Excursions
2 Stops
23h 35m
ONT - BFI
$ 252
Kiwi
Pick dates
9:25 AM - 9:25 PM
Air Excursions
1 Stops
12h 50m
ONT - BFI
$ 342
Kiwi
Pick dates
8:15 AM - 9:25 PM
Air Excursions
2 Stops
14h
ONT - BFI
$ 349
Kiwi
Pick dates

How to find the cheapest flight from Ontario (ONT) to Seattle (BFI)

Related info for your journey
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How to find the cheapest flight from Ontario (ONT) to Seattle (BFI)
Some placeholder content for the first accordion panel. This panel is shown by default, thanks to the .show class.
How to find the cheapest flight from Ontario (ONT) to Seattle (BFI)
Some placeholder content for the first accordion panel. This panel is shown by default, thanks to the .show class.