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

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1 Adults (11+)
0 Children (2~11)
0 Infants (0~2)
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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 September , October 2026

30 Sep - 28 Oct $ 1,097.00
STL
St Louis
Frontier Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
3 STOPS
STL
St Louis
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30 Sep - 28 Oct $ 1,111.00
STL
St Louis
Frontier Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
STL
St Louis
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30 Sep - 28 Oct $ 1,191.00
STL
St Louis
Frontier Airlines
3 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
STL
St Louis
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One-way flights to Seattle from St Louis

8:10 PM - 9:25 PM
Air Excursions
3 Stops
28h 5m
STL - BFI
$ 760
Kiwi
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8:10 PM - 4:05 PM
Air Excursions
3 Stops
22h 45m
STL - BFI
$ 839
Kiwi
Pick dates
8:10 PM - 9:25 PM
Air Excursions
2 Stops
28h 5m
STL - BFI
$ 897
Kiwi
Pick dates

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.