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Cheap Flights to Southern Illinois from HK$735

View HK$735 flight on Mon, 19 Oct 2026Opens in a new window

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Cheap round-trip flights to Southern Illinois

Prices were available within the past 7 days and start at HK$735 for one-way flights and HK$3,801 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

American Airlines
Contour Airlines
Contour Airlines
United
Delta

Frequently asked questions

How do I find cheap flights to Southern Illinois that have flexible change policies?
When it comes to flying these days, flexibility is key. That's why we have a "No change fee" search function to help you find flexible, low-priced tickets to Southern Illinois. It's on the left of your screen underneath the "Flexible change policies" heading.
Which airlines fly to Southern Illinois?
Work out your travel dates and then fly into or near Southern Illinois with one of these well-known airlines:
  • Southwest Airlines - 2,214 flights to or near Southern Illinois each month, including 2,214 flights to Lambert-St. Louis Intl. Airport (STL) per month.
  • American Airlines - 971 flights to or near Southern Illinois each month, including 789 flights to Lambert-St. Louis Intl. Airport (STL) per month.
  • Delta Air Lines - 728 flights to or near Southern Illinois each month, including 650 flights to Lambert-St. Louis Intl. Airport (STL) per month.
How can I find cheap tickets to Southern Illinois?
You'll always nab a fabulous deal with Expedia, but our "flexible dates" search function makes it that much easier. Enter your preferred travel date, then click on the flexible dates link above to see a list of prices for nearby days. HK$3,801 was the best price for a flight to Southern Illinois in the last seven days.
How much is a flight to Southern Illinois?
There were a lot of low-cost fares for the taking in the last seven days, with the price of a return ticket to Southern Illinois varying between HK$3,801 and HK$5,646. Many lucky travellers scored one-way seats from Chicago (ORD) for just HK$735.
What are the most popular airports to fly into in Southern Illinois?
Jet off to Southern Illinois and you'll have a few airports to decide between. Here are some of the region's busiest:
  • Lambert-St. Louis Intl. Airport (STL) - 4,902 flights per month.
  • Evansville Regional Airport (EVV) - 277 flights per month.
  • Williamson County Regional Airport (MWA) - 156 flights per month.
When is the cheapest time to fly to Southern Illinois?
If you'd prefer to spend your cash experiencing Southern Illinois rather than on your flight there, leave earlier in the week. The cheapest day to travel is normally Tuesday, with Monday a close second. With many folks travelling on the weekend, Saturday typically has the highest ticket prices.
How much is a plane ticket to Southern Illinois?
Airfares varied from HK$3,801 to HK$5,646 over the last seven days. When you're ready to book, we're here to help you pick up the best price to Southern Illinois.
What months are the cheapest to book a flight to Southern Illinois?
To pick up an awesome deal to Southern Illinois, book during February when prices are at their cheapest. The most expensive time to book? In the U.S, it's the festive month of December.

Travel information

Destination airport
Lambert-St. Louis Intl.
Destination airport IATA code
STL
Destination city name
St. Louis
Return price
HK$1,158

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