Flights to Southwest Illinois from Seattle - ￥17,840

View ￥17,840 flight on Wed, Jul 23, 2025Opens in a new window

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Cheap Flights from Seattle to Southwest Illinois (SEA-STL)

Prices were available within the past 7 days and start at ￥17,840 for one-way flights and ￥46,490 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

American Airlines
Sun, Aug 24 - Sun, Aug 31
SEA
Seattle
STL
St. Louis
￥46,490 Roundtrip, found 2 days ago
￥46,490
Roundtrip
found 2 days ago
Select American Airlines flight, departing Sun, Aug 24 from Seattle to St. Louis, returning Sun, Aug 31, priced at ￥46,490 found 2 days ago
American Airlines
Fri, Aug 8 - Sun, Aug 10
SEA
Seattle
STL
St. Louis
￥47,250 Roundtrip, found 16 hours ago
￥47,250
Roundtrip
found 16 hours ago
Select American Airlines flight, departing Fri, Aug 8 from Seattle to St. Louis, returning Sun, Aug 10, priced at ￥47,250 found 16 hours ago
Delta
Sun, Aug 24 - Sun, Aug 31
SEA
Seattle
STL
St. Louis
￥48,130 Roundtrip, found 2 days ago
￥48,130
Roundtrip
found 2 days ago
Select Delta flight, departing Sun, Aug 24 from Seattle to St. Louis, returning Sun, Aug 31, priced at ￥48,130 found 2 days ago
Delta
Sun, Aug 24 - Sun, Aug 31
SEA
Seattle
STL
St. Louis
￥49,080 Roundtrip, found 2 days ago
￥49,080
Roundtrip
found 2 days ago
Select Delta flight, departing Sun, Aug 24 from Seattle to St. Louis, returning Sun, Aug 31, priced at ￥49,080 found 2 days ago
American Airlines
Sun, Aug 24 - Sun, Aug 31
SEA
Seattle
STL
St. Louis
￥53,050 Roundtrip, found 2 days ago
￥53,050
Roundtrip
found 2 days ago
Select American Airlines flight, departing Sun, Aug 24 from Seattle to St. Louis, returning Sun, Aug 31, priced at ￥53,050 found 2 days ago
United
Sun, Aug 24 - Sun, Aug 31
SEA
Seattle
STL
St. Louis
￥56,180 Roundtrip, found 2 days ago
￥56,180
Roundtrip
found 2 days ago
Select United flight, departing Sun, Aug 24 from Seattle to St. Louis, returning Sun, Aug 31, priced at ￥56,180 found 2 days ago
*Available to Expedia members.