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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 June , July 2026

29 Jun - 30 Jul $ 867.00
ONT
Ontario
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
ONT
Ontario
Pick dates
29 Jun - 21 Jul $ 892.00
ONT
Ontario
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
ONT
Ontario
Pick dates
25 Jun - 30 Jul $ 918.00
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

25 Jun - 01 Jul $ 928.00
ONT
Ontario
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
3 STOPS
ONT
Ontario
Pick dates
22 Jun - 01 Jul $ 928.00
ONT
Ontario
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
3 STOPS
ONT
Ontario
Pick dates
25 Jun - 01 Jul $ 1,006.00
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

11:58 AM - 9:25 AM
Air Excursions
2 Stops
22h 17m
ONT - BFI
$ 464
Kiwi
Pick dates
11:58 AM - 6:45 AM
Air Excursions
2 Stops
19h 37m
ONT - BFI
$ 514
Kiwi
Pick dates
11:58 AM - 9:25 AM
Air Excursions
2 Stops
22h 17m
ONT - BFI
$ 514
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.