Cheap Flights from Chicago to Southern Illinois

View €39 flight on Sat, 16 Aug 2025Opens in a new window

Popular airlines from Chicago to Southern Illinois

  • Aer Lingus

    Aer Lingus

  • Lufthansa

    Lufthansa

  • British Airways

    British Airways

  • Turkish Airlines

    Turkish Airlines

  • American Airlines

    American Airlines

  • Air Serbia

    Air Serbia

  • Swiss International Air Lines

    Swiss International Air Lines

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Cheap flights from Chicago to Southern Illinois (CHI-STL)

Prices were available within the past 7 days and start at €39 for one-way flights and €78 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

American Airlines
Sat, 16 Aug - Mon, 18 Aug
ORD
Chicago
STL
St. Louis
€78 Return, found 3 days ago
€78
Return
found 3 days ago
Select American Airlines flight, departing Sat, 16 Aug from Chicago to St. Louis, returning Mon, 18 Aug, priced at €78 found 3 days ago
American Airlines
Sat, 9 Aug - Mon, 11 Aug
ORD
Chicago
STL
St. Louis
€81 Return, found 5 hours ago
€81
Return
found 5 hours ago
Select American Airlines flight, departing Sat, 9 Aug from Chicago to St. Louis, returning Mon, 11 Aug, priced at €81 found 5 hours ago
United
Sun, 5 Oct - Thu, 9 Oct
ORD
Chicago
STL
St. Louis
€104 Return, found 3 days ago
€104
Return
found 3 days ago
Select United flight, departing Sun, 5 Oct from Chicago to St. Louis, returning Thu, 9 Oct, priced at €104 found 3 days ago
American Airlines
Sat, 30 Aug - Sun, 31 Aug
ORD
Chicago
STL
St. Louis
€104 Return, found 1 day ago
€104
Return
found 1 day ago
Select American Airlines flight, departing Sat, 30 Aug from Chicago to St. Louis, returning Sun, 31 Aug, priced at €104 found 1 day ago
Southern Airways Express
Sun, 5 Oct - Thu, 9 Oct
ORD
Chicago
STL
St. Louis
€126 Return, found 3 days ago
€126
Return
found 3 days ago
Select Southern Airways Express flight, departing Sun, 5 Oct from Chicago to St. Louis, returning Thu, 9 Oct, priced at €126 found 3 days ago
Delta
Sat, 9 Aug - Mon, 11 Aug
ORD
Chicago
STL
St. Louis
€145 Return, found 5 hours ago
€145
Return
found 5 hours ago
Select Delta flight, departing Sat, 9 Aug from Chicago to St. Louis, returning Mon, 11 Aug, priced at €145 found 5 hours ago
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