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

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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 February , March 2026

23 Feb - 09 Mar $ 984.00
PHL
Philadelphia
Frontier Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
PHL
Philadelphia
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23 Feb - 06 Mar $ 984.00
PHL
Philadelphia
Frontier Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
PHL
Philadelphia
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23 Feb - 08 Mar $ 1,002.00
PHL
Philadelphia
Frontier Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
PHL
Philadelphia
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Last minute flights from Philadelphia to Seattle

19 Feb - 02 Mar $ 1,495.00
PHL
Philadelphia
Frontier Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
3 STOPS
PHL
Philadelphia
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23 Feb - 02 Mar $ 1,562.00
PHL
Philadelphia
Frontier Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
3 STOPS
PHL
Philadelphia
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27 Feb - 02 Mar $ 1,576.00
PHL
Philadelphia
Frontier Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
3 STOPS
PHL
Philadelphia
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One-way flights to Seattle from Philadelphia

3:15 PM - 7:35 AM
Air Excursions
3 Stops
44h 10m
PHL - BFI
$ 511
Kiwi
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5:30 AM - 5:35 AM
Air Excursions
3 Stops
27h 55m
PHL - BFI
$ 578
Kiwi
Pick dates
5:30 AM - 7:35 AM
Air Excursions
3 Stops
29h 55m
PHL - BFI
$ 591
Kiwi
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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.