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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 May , June 2026

28 May - 03 Jun $ 777.00
PHL
Philadelphia
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
3 STOPS
PHL
Philadelphia
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28 May - 02 Jun $ 836.00
PHL
Philadelphia
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
PHL
Philadelphia
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27 May - 02 Jun $ 904.00
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

28 May - 31 May $ 926.00
PHL
Philadelphia
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
3 STOPS
PHL
Philadelphia
Pick dates
28 May - 31 May $ 947.00
PHL
Philadelphia
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
PHL
Philadelphia
Pick dates
28 May - 31 May $ 1,015.00
PHL
Philadelphia
Frontier Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
PHL
Philadelphia
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One-way flights to Seattle from Philadelphia

8:35 PM - 9:25 PM
Air Excursions
2 Stops
28h 40m
PHL - BFI
$ 340
Kiwi
Pick dates
8:35 PM - 4:05 PM
Air Excursions
3 Stops
23h 20m
PHL - BFI
$ 408
Kiwi
Pick dates
8:35 PM - 4:05 PM
Air Excursions
3 Stops
23h 20m
PHL - BFI
$ 408
Kiwi
Pick dates

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)
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.