Cheap flights from Montreal to Southern Illinois from CA $258

View CA $258 flight on Thu, Nov. 13, 2025Opens in a new window

Popular airlines from Montreal to Southern Illinois

  • Air Canada

    Air Canada

  • WestJet

    WestJet

  • Flair Airlines

    Flair Airlines

  • American Airlines

    American Airlines

  • United

    United

  • Delta

    Delta

  • Porter Airlines

    Porter Airlines

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Cheap flights from Montreal (YMQ) to Southern Illinois (STL)

Prices were available within the past 7 days and start at CA $258 for one-way flights and CA $434 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

American Airlines
Tue, Nov. 4 - Wed, Nov. 12
YUL
Montreal
STL
St. Louis
CA $434 Roundtrip, found 5 days ago
CA $434
Roundtrip
found 5 days ago
Select American Airlines flight, departing Tue, Nov. 4 from Montreal to St. Louis, returning Wed, Nov. 12, priced at CA $434 found 5 days ago
American Airlines
Sat, Nov. 1 - Sat, Nov. 8
YUL
Montreal
STL
St. Louis
CA $434 Roundtrip, found 2 hours ago
CA $434
Roundtrip
found 2 hours ago
Select American Airlines flight, departing Sat, Nov. 1 from Montreal to St. Louis, returning Sat, Nov. 8, priced at CA $434 found 2 hours ago
American Airlines
Mon, Nov. 3 - Wed, Nov. 12
YUL
Montreal
STL
St. Louis
CA $438 Roundtrip, found 5 days ago
CA $438
Roundtrip
found 5 days ago
Select American Airlines flight, departing Mon, Nov. 3 from Montreal to St. Louis, returning Wed, Nov. 12, priced at CA $438 found 5 days ago
United
Tue, Nov. 18 - Thu, Nov. 27
YUL
Montreal
STL
St. Louis
CA $484 Roundtrip, found 5 days ago
CA $484
Roundtrip
found 5 days ago
Select United flight, departing Tue, Nov. 18 from Montreal to St. Louis, returning Thu, Nov. 27, priced at CA $484 found 5 days ago
Air Canada
Tue, Sep. 30 - Wed, Oct. 15
YUL
Montreal
STL
St. Louis
CA $523 Roundtrip, found 2 days ago
CA $523
Roundtrip
found 2 days ago
Select Air Canada flight, departing Tue, Sep. 30 from Montreal to St. Louis, returning Wed, Oct. 15, priced at CA $523 found 2 days ago
Delta
Wed, Oct. 1 - Tue, Oct. 14
YUL
Montreal
STL
St. Louis
CA $584 Roundtrip, found 5 days ago
CA $584
Roundtrip
found 5 days ago
Select Delta flight, departing Wed, Oct. 1 from Montreal to St. Louis, returning Tue, Oct. 14, priced at CA $584 found 5 days ago
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