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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 November , December 2025

26 Nov - 30 Dec $ 946.00
ONT
Ontario
Frontier Airlines
1 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
ONT
Ontario
Pick dates
23 Nov - 30 Dec $ 946.00
ONT
Ontario
Frontier Airlines
1 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
ONT
Ontario
Pick dates
26 Nov - 08 Dec $ 979.00
ONT
Ontario
Frontier Airlines
1 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
ONT
Ontario
Pick dates

Last minute flights from Ontario to Seattle

26 Nov - 30 Nov $ 1,029.00
ONT
Ontario
Frontier Airlines
1 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
1 STOPS
ONT
Ontario
Pick dates
23 Nov - 30 Nov $ 1,029.00
ONT
Ontario
Frontier Airlines
1 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
1 STOPS
ONT
Ontario
Pick dates
21 Nov - 30 Nov $ 1,080.00
ONT
Ontario
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
1 STOPS
ONT
Ontario
Pick dates

One-way flights to Seattle from Ontario

12:29 PM - 5:25 PM
Air Excursions
1 Stops
5h 46m
ONT - BFI
$ 515
Kiwi
Pick dates
12:29 PM - 5:45 PM
Air Excursions
1 Stops
6h 6m
ONT - BFI
$ 515
Kiwi
Pick dates
6:25 AM - 4:05 PM
Air Excursions
2 Stops
10h 30m
ONT - BFI
$ 565
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.