Cheap flights from Philadelphia to Southern Illinois

View AU$418 flight on Wed, 13 Aug. 2025Opens in a new window

Popular airlines from Philadelphia to Southern 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 Philadelphia (ILG) to Southern 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
Wed, 13 Aug. - Sun, 17 Aug.
PHL
Philadelphia
STL
St. Louis
AU$805 Return, found 11 hours ago
AU$805
Return
found 11 hours ago
Select American Airlines flight, departing Wed, 13 Aug. from Philadelphia to St. Louis, returning Sun, 17 Aug., priced at AU$805 found 11 hours ago
American Airlines
Wed, 13 Aug. - Sun, 17 Aug.
PHL
Philadelphia
STL
St. Louis
AU$820 Return, found 11 hours ago
AU$820
Return
found 11 hours ago
Select American Airlines flight, departing Wed, 13 Aug. from Philadelphia to St. Louis, returning Sun, 17 Aug., priced at AU$820 found 11 hours ago
American Airlines
Wed, 13 Aug. - Sun, 17 Aug.
PHL
Philadelphia
STL
St. Louis
AU$832 Return, found 11 hours ago
AU$832
Return
found 11 hours ago
Select American Airlines flight, departing Wed, 13 Aug. from Philadelphia to St. Louis, returning Sun, 17 Aug., priced at AU$832 found 11 hours ago
Delta
Wed, 13 Aug. - Sun, 17 Aug.
PHL
Philadelphia
STL
St. Louis
AU$835 Return, found 11 hours ago
AU$835
Return
found 11 hours ago
Select Delta flight, departing Wed, 13 Aug. from Philadelphia to St. Louis, returning Sun, 17 Aug., priced at AU$835 found 11 hours ago
United
Wed, 13 Aug. - Sun, 17 Aug.
PHL
Philadelphia
STL
St. Louis
AU$835 Return, found 11 hours ago
AU$835
Return
found 11 hours ago
Select United flight, departing Wed, 13 Aug. from Philadelphia to St. Louis, returning Sun, 17 Aug., priced at AU$835 found 11 hours ago
Alaska Airlines
Wed, 13 Aug. - Sun, 17 Aug.
PHL
Philadelphia
STL
St. Louis
AU$2,093 Return, found 11 hours ago
AU$2,093
Return
found 11 hours ago
Select Alaska Airlines flight, departing Wed, 13 Aug. from Philadelphia to St. Louis, returning Sun, 17 Aug., priced at AU$2,093 found 11 hours ago
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