Cheap flights from Seattle to Southwest Illinois

View AU$153 flight on Thu, 23 Oct. 2025Opens in a new window

Popular airlines from Seattle to Southwest Illinois

  • Jetstar

    Jetstar

  • Qantas Airways

    Qantas Airways

  • Virgin Australia

    Virgin Australia

  • Scoot

    Scoot

  • American Airlines

    American Airlines

  • Emirates

    Emirates

  • United

    United

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

Prices were available within the past 7 days for one-way flights and round trip tickets for the period specified. Prices and availability are subject to change. Additional terms apply.

Alaska Airlines
Tue, 23 Dec. - Fri, 2 Jan.
SEA
Seattle
STL
St. Louis
AU$670 Return, found 2 days ago
AU$670
Return
found 2 days ago
Select Alaska Airlines flight, departing Tue, 23 Dec. from Seattle to St. Louis, returning Fri, 2 Jan., priced at AU$670 found 2 days ago
Alaska Airlines
Tue, 23 Dec. - Fri, 2 Jan.
SEA
Seattle
STL
St. Louis
AU$686 Return, found 2 days ago
AU$686
Return
found 2 days ago
Select Alaska Airlines flight, departing Tue, 23 Dec. from Seattle to St. Louis, returning Fri, 2 Jan., priced at AU$686 found 2 days ago
Alaska Airlines
Tue, 23 Dec. - Fri, 2 Jan.
SEA
Seattle
STL
St. Louis
AU$733 Return, found 2 days ago
AU$733
Return
found 2 days ago
Select Alaska Airlines flight, departing Tue, 23 Dec. from Seattle to St. Louis, returning Fri, 2 Jan., priced at AU$733 found 2 days ago
Delta
Tue, 23 Dec. - Fri, 2 Jan.
SEA
Seattle
STL
St. Louis
AU$763 Return, found 2 days ago
AU$763
Return
found 2 days ago
Select Delta flight, departing Tue, 23 Dec. from Seattle to St. Louis, returning Fri, 2 Jan., priced at AU$763 found 2 days ago
United
Tue, 23 Dec. - Fri, 2 Jan.
SEA
Seattle
STL
St. Louis
AU$795 Return, found 2 days ago
AU$795
Return
found 2 days ago
Select United flight, departing Tue, 23 Dec. from Seattle to St. Louis, returning Fri, 2 Jan., priced at AU$795 found 2 days ago
American Airlines
Tue, 23 Dec. - Fri, 2 Jan.
SEA
Seattle
STL
St. Louis
AU$900 Return, found 2 days ago
AU$900
Return
found 2 days ago
Select American Airlines flight, departing Tue, 23 Dec. from Seattle to St. Louis, returning Fri, 2 Jan., priced at AU$900 found 2 days ago
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