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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 September , October 2026

30 Sep - 26 Oct $ 887.00
ONT
Ontario
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
ONT
Ontario
Pick dates
30 Sep - 23 Oct $ 916.00
ONT
Ontario
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
ONT
Ontario
Pick dates
30 Sep - 22 Oct $ 917.00
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

2:30 PM - 9:25 PM
Air Excursions
2 Stops
31h 45m
ONT - BFI
$ 537
Kiwi
Pick dates
2:30 PM - 4:05 PM
Air Excursions
2 Stops
26h 25m
ONT - BFI
$ 616
Kiwi
Pick dates
7:11 PM - 9:25 PM
Air Excursions
3 Stops
27h 4m
ONT - BFI
$ 719
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.