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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 May , June 2026

28 May - 03 Jun $ 780.00
STL
St Louis
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
3 STOPS
STL
St Louis
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04 May - 10 Jun $ 2,876.00
STL
St Louis
Alaska Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Alaska Airlines
2 STOPS
STL
St Louis
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04 May - 11 Jun $ 2,876.00
STL
St Louis
Alaska Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Alaska Airlines
2 STOPS
STL
St Louis
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Last minute flights from St Louis to Seattle

28 May - 01 Jun $ 900.00
STL
St Louis
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
STL
St Louis
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28 May - 01 Jun $ 961.00
STL
St Louis
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
3 STOPS
STL
St Louis
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25 May - 01 Jun $ 967.00
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

8:08 PM - 9:25 PM
Air Excursions
2 Stops
28h 7m
STL - BFI
$ 386
Kiwi
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8:08 PM - 9:25 PM
Air Excursions
2 Stops
28h 7m
STL - BFI
$ 392
Kiwi
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8:54 AM - 6:45 PM
Air Excursions
2 Stops
12h 41m
STL - BFI
$ 1,406
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.