Flights to Southwest Illinois, Illinois from NT$5,550

View NT$2,775 flight on Mon, 2026/1/26Opens 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 NT$2,775 for one-way flights and NT$5,550 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Delta
Mon, Jan 26 - Tue, Feb 3
SEA
Seattle
STL
St. Louis
NT$5,550 Roundtrip, found 19 hours ago
NT$5,550
Roundtrip
found 19 hours ago
Select Delta flight, departing Mon, Jan 26 from Seattle to St. Louis, returning Tue, Feb 3, priced at NT$5,550 found 19 hours ago
American Airlines
Mon, Jan 26 - Tue, Feb 3
SEA
Seattle
STL
St. Louis
NT$6,960 Roundtrip, found 19 hours ago
NT$6,960
Roundtrip
found 19 hours ago
Select American Airlines flight, departing Mon, Jan 26 from Seattle to St. Louis, returning Tue, Feb 3, priced at NT$6,960 found 19 hours ago
Alaska Airlines
Mon, Jan 26 - Tue, Feb 3
SEA
Seattle
STL
St. Louis
NT$11,078 Roundtrip, found 19 hours ago
NT$11,078
Roundtrip
found 19 hours ago
Select Alaska Airlines flight, departing Mon, Jan 26 from Seattle to St. Louis, returning Tue, Feb 3, priced at NT$11,078 found 19 hours ago
United
Mon, Jan 26 - Tue, Feb 3
SEA
Seattle
STL
St. Louis
NT$11,544 Roundtrip, found 19 hours ago
NT$11,544
Roundtrip
found 19 hours ago
Select United flight, departing Mon, Jan 26 from Seattle to St. Louis, returning Tue, Feb 3, priced at NT$11,544 found 19 hours ago
Air Canada
Sat, Jan 17 - Sat, Jan 24
YVR
Vancouver
STL
St. Louis
NT$13,239 Roundtrip, found 1 day ago
NT$13,239
Roundtrip
found 1 day ago
Select Air Canada flight, departing Sat, Jan 17 from Vancouver to St. Louis, returning Sat, Jan 24, priced at NT$13,239 found 1 day ago

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, NT$5,550 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 NT$5,550 and reached a maximum price of NT$27,016. For one-way trips departing from Seattle (SEA), the lowest amount paid during this time was only NT$2,775.
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 NT$5,550 and NT$27,016. 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.
Flights to Southwest Illinois information
Destination airport
Lambert-St. Louis Intl.
Destination airport IATA code
STL
Destination city name
St. Louis
Roundtrip price
NT$5,550

Trending flights to Southwest Illinois

Prices were available within the past 7 days and start at NT$2,775 for one-way flights and NT$5,550 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Cathay Pacific
Wed, Feb 25 - Mon, Mar 9
TPE
Taipei
STL
St. Louis
NT$27,016 Roundtrip, found 6 days ago
NT$27,016
Roundtrip
found 6 days ago
Select Cathay Pacific flight, departing Wed, Feb 25 from Taipei to St. Louis, returning Mon, Mar 9, priced at NT$27,016 found 6 days ago

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