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

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1 Adults (11+)
0 Children (2~11)
0 Infants (0~2)
Save up to 31%
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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

30 Sep - 31 Oct $ 1,302.00
BOS
Boston
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
3 STOPS
BOS
Boston
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30 Sep - 29 Oct $ 1,340.00
BOS
Boston
JetBlue Airways
2 STOPS
BFI
Seattle
BFI
Seattle
JetBlue Airways
2 STOPS
BOS
Boston
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30 Sep - 30 Oct $ 1,365.00
BOS
Boston
JetBlue Airways
2 STOPS
BFI
Seattle
BFI
Seattle
JetBlue Airways
2 STOPS
BOS
Boston
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One-way flights to Seattle from Boston

5:52 PM - 9:25 PM
Air Excursions
2 Stops
31h 23m
BOS - BFI
$ 855
Kiwi
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5:52 PM - 4:05 PM
Air Excursions
2 Stops
26h 3m
BOS - BFI
$ 935
Kiwi
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9:10 PM - 9:25 PM
Air Excursions
3 Stops
28h 5m
BOS - BFI
$ 1,160
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.