Flights to Southern Illinois from Seattle - ￥13,790

View ￥13,790 flight on Wed, Oct 1, 2025Opens in a new window

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

Prices were available within the past 7 days and start at ￥13,790 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 6 days ago
￥46,490
Roundtrip
found 6 days ago
Select American Airlines flight, departing Sun, Aug 24 from Seattle to St. Louis, returning Sun, Aug 31, priced at ￥46,490 found 6 days ago
American Airlines
Fri, Aug 8 - Sun, Aug 10
SEA
Seattle
STL
St. Louis
￥47,250 Roundtrip, found 3 days ago
￥47,250
Roundtrip
found 3 days ago
Select American Airlines flight, departing Fri, Aug 8 from Seattle to St. Louis, returning Sun, Aug 10, priced at ￥47,250 found 3 days ago
Delta
Sun, Aug 24 - Sun, Aug 31
SEA
Seattle
STL
St. Louis
￥48,130 Roundtrip, found 6 days ago
￥48,130
Roundtrip
found 6 days ago
Select Delta flight, departing Sun, Aug 24 from Seattle to St. Louis, returning Sun, Aug 31, priced at ￥48,130 found 6 days ago
Delta
Sun, Aug 24 - Sun, Aug 31
SEA
Seattle
STL
St. Louis
￥49,080 Roundtrip, found 6 days ago
￥49,080
Roundtrip
found 6 days ago
Select Delta flight, departing Sun, Aug 24 from Seattle to St. Louis, returning Sun, Aug 31, priced at ￥49,080 found 6 days ago
Delta
Mon, Aug 11 - Thu, Aug 14
SEA
Seattle
STL
St. Louis
￥50,480 Roundtrip, found 1 day ago
￥50,480
Roundtrip
found 1 day ago
Select Delta flight, departing Mon, Aug 11 from Seattle to St. Louis, returning Thu, Aug 14, priced at ￥50,480 found 1 day ago
United
Sun, Aug 24 - Sun, Aug 31
SEA
Seattle
STL
St. Louis
￥56,180 Roundtrip, found 6 days ago
￥56,180
Roundtrip
found 6 days ago
Select United flight, departing Sun, Aug 24 from Seattle to St. Louis, returning Sun, Aug 31, priced at ￥56,180 found 6 days ago
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