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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 April , May 2026

30 Apr - 08 May $ 646.00
ONT
Ontario
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
ONT
Ontario
Pick dates
30 Apr - 29 May $ 646.00
ONT
Ontario
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
ONT
Ontario
Pick dates
30 Apr - 08 May $ 657.00
ONT
Ontario
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
ONT
Ontario
Pick dates

Last minute flights from Ontario to Seattle

29 Apr - 30 Apr $ 727.00
ONT
Ontario
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
ONT
Ontario
Pick dates
28 Apr - 30 Apr $ 727.00
ONT
Ontario
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
ONT
Ontario
Pick dates
28 Apr - 30 Apr $ 853.00
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

12:59 AM - 2:45 PM
Air Excursions
2 Stops
14h 36m
ONT - BFI
$ 311
Kiwi
Pick dates
12:59 AM - 2:45 PM
Air Excursions
2 Stops
14h 36m
ONT - BFI
$ 323
Kiwi
Pick dates
12:59 AM - 2:45 PM
Air Excursions
2 Stops
14h 36m
ONT - BFI
$ 323
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.