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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 March , April 2026

20 Mar - 22 Apr $ 954.00
BOS
Boston
Spirit Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Spirit Airlines
3 STOPS
BOS
Boston
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20 Mar - 29 Apr $ 970.00
BOS
Boston
Frontier Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
3 STOPS
BOS
Boston
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20 Mar - 16 Apr $ 976.00
BOS
Boston
Spirit Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Spirit Airlines
3 STOPS
BOS
Boston
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Last minute flights from Boston to Seattle

17 Mar - 01 Apr $ 1,322.00
BOS
Boston
Porter Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Porter Airlines
3 STOPS
BOS
Boston
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23 Mar - 01 Apr $ 1,323.00
BOS
Boston
Porter Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Porter Airlines
3 STOPS
BOS
Boston
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25 Mar - 01 Apr $ 1,402.00
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

1:18 PM - 3:05 PM
Air Excursions
3 Stops
29h 37m
BOS - BFI
$ 527
Kiwi
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12:09 PM - 2:45 PM
Air Excursions
3 Stops
30h 26m
BOS - BFI
$ 595
Kiwi
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11:51 AM - 2:45 PM
Air Excursions
3 Stops
30h 44m
BOS - BFI
$ 600
Kiwi
Pick dates

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.