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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 April , May 2026

28 Apr - 09 May $ 875.00
BOS
Boston
Sun Country Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Sun Country Airlines
2 STOPS
BOS
Boston
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26 Apr - 09 May $ 960.00
BOS
Boston
Sun Country Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Sun Country Airlines
2 STOPS
BOS
Boston
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30 Apr - 09 May $ 971.00
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

28 Apr - 01 May $ 877.00
BOS
Boston
Sun Country Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Sun Country Airlines
3 STOPS
BOS
Boston
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28 Apr - 01 May $ 919.00
BOS
Boston
Sun Country Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Sun Country Airlines
2 STOPS
BOS
Boston
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26 Apr - 01 May $ 1,005.00
BOS
Boston
Sun Country Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Sun Country Airlines
2 STOPS
BOS
Boston
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One-way flights to Seattle from Boston

12:31 PM - 2:45 PM
Air Excursions
3 Stops
30h 4m
BOS - BFI
$ 440
Kiwi
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9:00 AM - 8:15 AM
Air Excursions
2 Stops
27h 5m
BOS - BFI
$ 486
Kiwi
Pick dates
11:40 AM - 6:45 AM
Air Excursions
2 Stops
22h 55m
BOS - BFI
$ 497
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.