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

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0 Children (2~11)
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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 February , March 2026

20 Feb - 06 Mar $ 815.00
ONT
Ontario
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
ONT
Ontario
Pick dates
20 Feb - 09 Mar $ 815.00
ONT
Ontario
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
ONT
Ontario
Pick dates
20 Feb - 08 Mar $ 833.00
ONT
Ontario
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
ONT
Ontario
Pick dates

One-way flights to Seattle from Ontario

7:22 PM - 7:35 AM
Air Excursions
2 Stops
37h 3m
ONT - BFI
$ 402
Kiwi
Pick dates
8:07 AM - 7:35 AM
Air Excursions
2 Stops
24h 18m
ONT - BFI
$ 430
Kiwi
Pick dates
8:07 AM - 7:35 AM
Air Excursions
2 Stops
24h 18m
ONT - BFI
$ 519
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.