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Cheap flights from Boston (BOS) 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 Boston (BOS) to Seattle (BFI)

How to find the cheapest flight from Boston (BOS) to Seattle (BFI)
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How to find the cheapest flight from Boston (BOS) to Seattle (BFI)
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How to find the cheapest flight from Boston (BOS) to Seattle (BFI)
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Cheap flights from Boston to Seattle in September , October 2026

29 Sep - 24 Oct $ 932.00
BOS
Boston
Frontier Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
3 STOPS
BOS
Boston
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25 Sep - 24 Oct $ 936.00
BOS
Boston
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
3 STOPS
BOS
Boston
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25 Sep - 26 Oct $ 992.00
BOS
Boston
Sun Country Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Sun Country Airlines
2 STOPS
BOS
Boston
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Last minute flights from Boston to Seattle

29 Sep - 02 Oct $ 1,036.00
BOS
Boston
Frontier Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
3 STOPS
BOS
Boston
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25 Sep - 02 Oct $ 1,040.00
BOS
Boston
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
3 STOPS
BOS
Boston
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29 Sep - 01 Oct $ 1,167.00
BOS
Boston
Porter Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Porter Airlines
3 STOPS
BOS
Boston
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One-way flights to Seattle from Boston

12:54 PM - 6:45 PM
Air Excursions
3 Stops
33h 41m
BOS - BFI
$ 446
Kiwi
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11:20 AM - 9:25 PM
Air Excursions
2 Stops
13h 55m
BOS - BFI
$ 585
Kiwi
Pick dates
11:50 AM - 9:25 PM
Air Excursions
2 Stops
13h 25m
BOS - BFI
$ 624
Kiwi
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How to find the cheapest flight from Boston (BOS) to Seattle (BFI)

Related info for your journey
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How to find the cheapest flight from Boston (BOS) 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 Boston (BOS) to Seattle (BFI)
Some placeholder content for the first accordion panel. This panel is shown by default, thanks to the .show class.