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

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0 Children (2~11)
0 Infants (0~2)
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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 June , July 2026

30 Jun - 22 Jul $ 1,113.00
ONT
Ontario
Frontier Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
ONT
Ontario
Pick dates
30 Jun - 29 Jul $ 1,113.00
ONT
Ontario
Frontier Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
ONT
Ontario
Pick dates
30 Jun - 21 Jul $ 1,114.00
ONT
Ontario
Frontier Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
ONT
Ontario
Pick dates

One-way flights to Seattle from Ontario

8:36 PM - 6:45 PM
Air Excursions
3 Stops
22h 59m
ONT - BFI
$ 807
Kiwi
Pick dates
9:36 PM - 6:45 AM
Air Excursions
3 Stops
33h 59m
ONT - BFI
$ 921
Kiwi
Pick dates
9:36 PM - 6:45 PM
Air Excursions
3 Stops
21h 59m
ONT - BFI
$ 1,196
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.