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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 August , September 2026

31 Aug - 01 Sep $ 829.00
PHL
Philadelphia
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
PHL
Philadelphia
Pick dates
27 Aug - 01 Sep $ 866.00
PHL
Philadelphia
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
PHL
Philadelphia
Pick dates
30 Aug - 01 Sep $ 866.00
PHL
Philadelphia
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
PHL
Philadelphia
Pick dates

Last minute flights from Philadelphia to Seattle

27 Aug - 31 Aug $ 866.00
PHL
Philadelphia
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
PHL
Philadelphia
Pick dates
30 Aug - 31 Aug $ 866.00
PHL
Philadelphia
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
PHL
Philadelphia
Pick dates
28 Aug - 31 Aug $ 891.00
PHL
Philadelphia
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
PHL
Philadelphia
Pick dates

One-way flights to Seattle from Philadelphia

8:00 AM - 9:25 PM
Air Excursions
2 Stops
17h 15m
PHL - BFI
$ 415
Kiwi
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7:00 AM - 4:05 PM
Air Excursions
2 Stops
12h 55m
PHL - BFI
$ 452
Kiwi
Pick dates
7:00 AM - 4:20 PM
Air Excursions
2 Stops
13h 10m
PHL - BFI
$ 452
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.