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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)
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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 January , February 2026

28 Jan - 07 Feb $ 886.00
BOS
Boston
Spirit Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Spirit Airlines
3 STOPS
BOS
Boston
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28 Jan - 24 Feb $ 909.00
BOS
Boston
Frontier Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
3 STOPS
BOS
Boston
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28 Jan - 06 Feb $ 982.00
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

28 Jan - 02 Feb $ 1,056.00
BOS
Boston
Frontier Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
3 STOPS
BOS
Boston
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28 Jan - 02 Feb $ 1,170.00
BOS
Boston
Spirit Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Spirit Airlines
3 STOPS
BOS
Boston
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28 Jan - 02 Feb $ 1,192.00
BOS
Boston
Spirit Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Spirit Airlines
3 STOPS
BOS
Boston
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One-way flights to Seattle from Boston

5:34 AM - 2:45 PM
Air Excursions
3 Stops
37h 1m
BOS - BFI
$ 440
Kiwi
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5:27 PM - 4:05 PM
Air Excursions
3 Stops
50h 28m
BOS - BFI
$ 541
Kiwi
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3:43 PM - 2:45 PM
Air Excursions
3 Stops
50h 52m
BOS - BFI
$ 698
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.