Cheap Flights to Southwest Illinois , IL from CA $276

View CA $276 flight on Wed, Apr 15, 2026Opens in a new window

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How much is the cheapest flight to Southwest Illinois?

Prices were available within the past 7 days and start at CA $276 for one-way flights and CA $514 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

American Airlines
Wed, May 13 - Tue, May 19
YYZ
Toronto
STL
St. Louis
CA $551 Roundtrip, found 4 hours ago
CA $551
Roundtrip
found 4 hours ago
Select American Airlines flight, departing Wed, May 13 from Toronto to St. Louis, returning Tue, May 19, priced at CA $551 found 4 hours ago
Delta
Wed, Apr 15 - Wed, Apr 22
YYZ
Toronto
STL
St. Louis
CA $558 Roundtrip, found 1 day ago
CA $558
Roundtrip
found 1 day ago
Select Delta flight, departing Wed, Apr 15 from Toronto to St. Louis, returning Wed, Apr 22, priced at CA $558 found 1 day ago
American Airlines
Wed, May 13 - Tue, May 19
YYZ
Toronto
STL
St. Louis
CA $564 Roundtrip, found 4 hours ago
CA $564
Roundtrip
found 4 hours ago
Select American Airlines flight, departing Wed, May 13 from Toronto to St. Louis, returning Tue, May 19, priced at CA $564 found 4 hours ago
Air Canada
Fri, Jun 5 - Tue, Jun 9
YYZ
Toronto
STL
St. Louis
CA $583 Roundtrip, found 6 days ago
CA $583
Roundtrip
found 6 days ago
Select Air Canada flight, departing Fri, Jun 5 from Toronto to St. Louis, returning Tue, Jun 9, priced at CA $583 found 6 days ago
WestJet
Thu, May 14 - Tue, May 19
YYZ
Toronto
STL
St. Louis
CA $699 Roundtrip, found 8 hours ago
CA $699
Roundtrip
found 8 hours ago
Select WestJet flight, departing Thu, May 14 from Toronto to St. Louis, returning Tue, May 19, priced at CA $699 found 8 hours ago

Frequently asked questions

How do I find cheap flights to Southwest Illinois that have flexible change policies?
At Expedia, we've been channeling our inner Olympic gymnast to deliver you the most flexible airfares on the market. Simply check the "No change fee" box under the "Flexible change policies" filter to find the best flights to Southwest Illinois.
Which airlines fly to Southwest Illinois?
When you're ready to book your ticket to or near Southwest Illinois, these well-known airlines look forward to welcoming you aboard:

  • Southwest Airlines - 2,907 flights to or near Southwest Illinois each month, including 2,907 flights to Lambert-St. Louis Intl. Airport (STL) per month.
  • American Airlines - 1,023 flights to or near Southwest Illinois each month, including 810 flights to Lambert-St. Louis Intl. Airport (STL) per month.
  • Delta - 602 flights to or near Southwest Illinois each month, including 516 flights to Lambert-St. Louis Intl. Airport (STL) per month.

How can I find cheap tickets to Southwest Illinois?
A helpful strategy for picking up cheap fares is to be flexible with your travel dates. Begin with searching for your flight to Southwest Illinois, then click on the "flexible dates" box for a list of prices for nearby days. Another tip? Book well in advance. To give you an idea of fares, CA $514 was the lowest price for a flight to Southwest Illinois in the last seven days.
How much is a flight to Southwest Illinois?
You could have purchased a round-trip ticket to Southwest Illinois from anywhere between CA $514 and CA $699 in the last seven days. For one-way journeys departing from Toronto (YYZ), the lowest amount paid during this time was CA $276.
What are the most popular airports to fly into in Southwest Illinois?
Choosing your airport comes down to factors such as your airline, budget and where you plan to explore. These are your two options in Southwest Illinois:

  • Lambert-St. Louis Intl. Airport (STL) - 5,094 flights per month.
  • Evansville Regional Airport (EVV) - 325 flights per month.

When is the cheapest time to fly to Southwest Illinois?
If you'd prefer to spend your vacation money experiencing the delights of Southwest Illinois rather than on your trip there, depart earlier in the week. The most cost-effective day to fly is normally Tuesday, followed by Monday. With many folks travelling over the weekend, Saturday tends to have the highest fares.
How much is a plane ticket to Southwest Illinois?
Plane tickets ranged from CA $514 to CA $699 over the last seven days. When you're ready to book, we're here to help you land the best deal to Southwest Illinois.
What are the best things to do in Southwest Illinois?

  • Get your vacation underway in the exciting city of Alton and you'll have an almost endless selection of attractions to discover. Argosy Casino is just one place to start. You'll want to experience the nightlife, taste the local cuisine and shop up a storm while you're in town as well.
  • When it comes to packing for your vacation, it's always handy to know just what the weather will be like. Alton has a humid subtropical climate, but look up the local forecast to get a clearer idea of temperatures during your visit.

What is the best time to go to Southwest Illinois?
If you like your days to sizzle like an outdoor barbecue, head to Southwest Illinois anytime after June 20. This is the beginning of the summer season, when temperatures normally fluctuate between 19ºC and 29ºC in the main city of Belleville. April, May and June are the most popular months to discover the wonders of this destination.
What months are the cheapest to book a flight to Southwest Illinois?
February is the perfect month to secure an impressive deal to Southwest Illinois. Bear in mind that the costliest time to purchase tickets in the USA isn't during the height of summer, but the festive month of December.

Book with confidence

Expedia.ca gives you the best tools to secure great deals on flights to Southwest Illinois. Use our easy and convenient booking engine to browse nonstop flights and convenient departure points every day of the year. Search airfares from the top airlines to book your perfect flight to Southwest Illinois. Whatever your travel needs, you can always rely on Expedia.ca to help you find cheap flights to Southwest Illinois.

Using our booking engine is simple - just type in your points of travel and preferred dates and Expedia.ca does the rest! If your travel times are flexible, you can find even better bargains by adjusting your flight dates. Browse connecting flights to increase your chances of finding even lower fares. Thanks to Expedia's Best Price Guarantee, you can book your Southwest Illinois flights with full confidence knowing that you've found the best deal online.

Expedia.ca makes the booking process easy and stress-free by offering support along the entire way. Our friendly staff is available 24 hours a day to provide assistance and help you book your ticket. Call us toll-free at 1-888-397-3342 to answer any questions that you may have about your trip to Southwest Illinois.

Looking to save even more? Get additional savings by bundling your Southwest Illinois flight with a hotel and/or car rental to create a bargain travel package. Early birds can discover terrific savings by booking in advance while last minute travelers can enjoy great last minute deals. With Expedia.ca, there's no shortage of options to save even more on your Southwest Illinois trip!

Travel information

Destination airport
Lambert-St. Louis Intl.
Destination airport IATA code
STL
Destination city name
St. Louis
Roundtrip price
CA $362

Trending flights to Southwest Illinois

Prices were available within the past 7 days and start at CA $276 for one-way flights and CA $514 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Air Canada
Thu, Sep 3 - Tue, Sep 8
YYC
Calgary
STL
St. Louis
CA $514 Roundtrip, found 14 hours ago
CA $514
Roundtrip
found 14 hours ago
Select Air Canada flight, departing Thu, Sep 3 from Calgary to St. Louis, returning Tue, Sep 8, priced at CA $514 found 14 hours ago

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