Cheap flights from Washington to Southwest Illinois

View AU$137 flight on Wed, 27 Aug. 2025Opens in a new window

Popular airlines from Washington 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 Washington (WAS) 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.

American Airlines
Sat, 6 Sep. - Sat, 13 Sep.
BWI
Baltimore
STL
St. Louis
AU$272 Return, found 1 day ago
AU$272
Return
found 1 day ago
Select American Airlines flight, departing Sat, 6 Sep. from Baltimore to St. Louis, returning Sat, 13 Sep., priced at AU$272 found 1 day ago
American Airlines
Sat, 6 Sep. - Sat, 13 Sep.
DCA
Washington
STL
St. Louis
AU$275 Return, found 1 day ago
AU$275
Return
found 1 day ago
Select American Airlines flight, departing Sat, 6 Sep. from Washington to St. Louis, returning Sat, 13 Sep., priced at AU$275 found 1 day ago
Delta
Sat, 6 Sep. - Sat, 13 Sep.
IAD
Washington
STL
St. Louis
AU$305 Return, found 1 day ago
AU$305
Return
found 1 day ago
Select Delta flight, departing Sat, 6 Sep. from Washington to St. Louis, returning Sat, 13 Sep., priced at AU$305 found 1 day ago
Delta
Sat, 6 Sep. - Sat, 13 Sep.
DCA
Washington
STL
St. Louis
AU$305 Return, found 1 day ago
AU$305
Return
found 1 day ago
Select Delta flight, departing Sat, 6 Sep. from Washington to St. Louis, returning Sat, 13 Sep., priced at AU$305 found 1 day ago
American Airlines
Sun, 31 Aug. - Sun, 7 Sep.
BWI
Baltimore
STL
St. Louis
AU$307 Return, found 6 days ago
AU$307
Return
found 6 days ago
Select American Airlines flight, departing Sun, 31 Aug. from Baltimore to St. Louis, returning Sun, 7 Sep., priced at AU$307 found 6 days ago
United
Sat, 6 Sep. - Sat, 13 Sep.
IAD
Washington
STL
St. Louis
AU$344 Return, found 1 day ago
AU$344
Return
found 1 day ago
Select United flight, departing Sat, 6 Sep. from Washington to St. Louis, returning Sat, 13 Sep., priced at AU$344 found 1 day ago
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