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Cheap Flights to Southwest Illinois from HK$703

View HK$703 flight on Mon, 5 Oct 2026Opens in a new window

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Cheap round-trip flights to Southwest Illinois

Prices were available within the past 7 days and start at HK$703 for one-way flights and HK$1,158 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Delta
Delta
Delta
American Airlines
United

Frequently asked questions

How do I find cheap flights to Southwest Illinois that have flexible change policies?
By using our neat "No change fee" filter, that's how. Just enter your travel details, click "Search," then tick the checkbox directly underneath the "Flexible change policies" heading (top left-hand side of your screen). Expedia makes it a cinch to find flexible and affordable tickets to Southwest Illinois.
Which airlines fly to Southwest Illinois?
When you're ready to reserve your ticket to or near Southwest Illinois, these popular carriers are waiting to welcome you on board:
  • Southwest Airlines - 2,214 flights to or near Southwest Illinois each month, including 2,214 flights to Lambert-St. Louis Intl. Airport (STL) per month.
  • American Airlines - 971 flights to or near Southwest Illinois each month, including 789 flights to Lambert-St. Louis Intl. Airport (STL) per month.
  • Delta Air Lines - 728 flights to or near Southwest Illinois each month, including 650 flights to Lambert-St. Louis Intl. Airport (STL) per month.
How can I find cheap tickets to Southwest Illinois?
In the last seven days, HK$1,158 was the best price for a flight to Southwest Illinois. If you'd love to save even more, book in advance and be flexible with your travel dates. Search for your flight to Southwest Illinois, then see prices for similar time frames by clicking on the "flexible dates" link above.
How much is a flight to Southwest Illinois?
In the last seven days, round-trip tickets to Southwest Illinois sold for as little as HK$1,158 and reached a maximum price of HK$2,300. For one-way trips departing from Atlanta (ATL), the lowest amount paid during this time was only HK$703.
What are the most popular airports to fly into in Southwest Illinois?
Choosing your airport comes down to factors including your airline, budget and where you plan to explore. These are your choices in Southwest Illinois:
  • Lambert-St. Louis Intl. Airport (STL) - 4,902 flights per month.
  • Evansville Regional Airport (EVV) - 277 flights per month.
When is the cheapest time to fly to Southwest Illinois?
Consider jetting off earlier in the week to book the best airfare to Southwest Illinois. Tuesday is usually the most affordable day to fly, with Monday right behind it. Saturday often has the most expensive ticket prices. This is because a lot of people choose to begin their trip on a weekend.
How much is a plane ticket to Southwest Illinois?
In the last seven days, plane tickets to Southwest Illinois ranged between HK$1,158 and HK$2,300. Prices depend on multiple things, particularly the time of departure, carrier, cabin class and when the fare is booked.
What months are the cheapest to book a flight to Southwest Illinois?
The most affordable month to score a terrific deal to Southwest Illinois is February, while the priciest month is December. Avoid this month if you're looking to save money.

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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