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Cheap flights from St Louis (STL) to Seattle (BFI)

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0 Children (2~11)
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How to find the cheapest flight from St Louis (STL) to Seattle (BFI)

How to find the cheapest flight from St Louis (STL) to Seattle (BFI)
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How to find the cheapest flight from St Louis (STL) to Seattle (BFI)
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How to find the cheapest flight from St Louis (STL) to Seattle (BFI)
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Cheap flights from St Louis to Seattle in January , February 2026

28 Jan - 05 Feb $ 934.00
STL
St Louis
Frontier Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
STL
St Louis
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21 Jan - 05 Feb $ 968.00
STL
St Louis
Frontier Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
STL
St Louis
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29 Jan - 05 Feb $ 1,033.00
STL
St Louis
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
STL
St Louis
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Last minute flights from St Louis to Seattle

28 Jan - 02 Feb $ 951.00
STL
St Louis
Frontier Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
3 STOPS
STL
St Louis
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21 Jan - 02 Feb $ 986.00
STL
St Louis
Frontier Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
3 STOPS
STL
St Louis
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29 Jan - 02 Feb $ 1,051.00
STL
St Louis
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
3 STOPS
STL
St Louis
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One-way flights to Seattle from St Louis

3:46 PM - 2:45 PM
Air Excursions
3 Stops
25h 49m
STL - BFI
$ 460
Kiwi
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3:46 PM - 2:45 PM
Air Excursions
3 Stops
25h 49m
STL - BFI
$ 494
Kiwi
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10:01 PM - 2:45 PM
Air Excursions
2 Stops
19h 34m
STL - BFI
$ 559
Kiwi
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How to find the cheapest flight from St Louis (STL) to Seattle (BFI)

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