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Cheap flights from Philadelphia (PHL) to Seattle (BFI)

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0 Children (2~11)
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How to find the cheapest flight from Philadelphia (PHL) to Seattle (BFI)

How to find the cheapest flight from Philadelphia (PHL) to Seattle (BFI)
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How to find the cheapest flight from Philadelphia (PHL) to Seattle (BFI)
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How to find the cheapest flight from Philadelphia (PHL) to Seattle (BFI)
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Cheap flights from Philadelphia to Seattle in December 2025 , January 2026

23 Dec - 13 Jan $ 1,041.00
PHL
Philadelphia
Frontier Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
3 STOPS
PHL
Philadelphia
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20 Dec - 13 Jan $ 1,107.00
PHL
Philadelphia
Frontier Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
3 STOPS
PHL
Philadelphia
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22 Dec - 13 Jan $ 1,108.00
PHL
Philadelphia
Frontier Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
3 STOPS
PHL
Philadelphia
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Last minute flights from Philadelphia to Seattle

23 Dec - 01 Jan $ 1,153.00
PHL
Philadelphia
Sun Country Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Sun Country Airlines
2 STOPS
PHL
Philadelphia
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20 Dec - 01 Jan $ 1,220.00
PHL
Philadelphia
Sun Country Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Sun Country Airlines
2 STOPS
PHL
Philadelphia
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22 Dec - 01 Jan $ 1,221.00
PHL
Philadelphia
Sun Country Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Sun Country Airlines
2 STOPS
PHL
Philadelphia
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One-way flights to Seattle from Philadelphia

1:54 PM - 5:25 PM
Air Excursions
3 Stops
31h 21m
PHL - BFI
$ 590
Kiwi
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8:36 PM - 5:45 PM
Air Excursions
3 Stops
24h 59m
PHL - BFI
$ 657
Kiwi
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8:41 PM - 6:45 PM
Air Excursions
3 Stops
25h 54m
PHL - BFI
$ 658
Kiwi
Pick dates

How to find the cheapest flight from Philadelphia (PHL) to Seattle (BFI)

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