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Decatur

$291+ Cheap flights from St. Louis to Decatur, IL (STL - DEC)

This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 10/4. Fares are subject to change and may not be available on all flights or dates of travel.
STL — DEC
Oct 15 — Oct 221
Wed 10/15
Wed 10/22
1 adult, Economy
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Cheap flight deals from St. Louis to Decatur

Discover tips and strategies to find the most affordable flight options for your journey from St. Louis (STL) to Decatur (DEC). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated September 15, 2025.

Round-trip from

$291
(United Airlines)
From Lambert-St Louis to Decatur Arpt
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Find flight deals from St. Louis to Decatur

Cheapest flights from St. Louis to Decatur
Explore the most affordable flight options available from St. Louis to Decatur. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 15, 2025.

This United Airlines deal was found by Cheapflights users on 9/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/45:28 pmSTL - DEC
1 stop15h 23mUnited Airlines
Tue 10/79:38 amDEC - STL
1 stop4h 49mUnited Airlines
Deal found 9/11$291
This United Airlines deal was found by Cheapflights users on 9/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/275:24 pmSTL - DEC
1 stop24h 28mUnited Airlines
Mon 11/37:08 pmDEC - STL
1 stop20h 39mUnited Airlines
Deal found 9/12$324
This United Airlines deal was found by Cheapflights users on 9/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/2912:25 pmSTL - DEC
1 stop5h 39mUnited Airlines
Fri 10/36:55 pmDEC - STL
1 stop23h 22mUnited Airlines
Deal found 9/13$496
This United Airlines deal was found by Cheapflights users on 9/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/1212:35 pmSTL - DEC
1 stop5h 24mUnited Airlines
Sun 9/149:42 amDEC - STL
1 stop4h 37mUnited Airlines
Deal found 9/11$515

Cheapflights Fare Finder

 
Customize your flight search to find flights from St. Louis to Decatur that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated September 15, 2025.
Use the filters below to find and compare flights from St. Louis to Decatur that are best for you.

Fly from

St. Louis

Fly to

Decatur

Route

Depart

Return

Price

St. LouisDecatur

STL - DEC

STLDEC

Lambert-St Louis

Sat 10/4

5:28 pm-8:51 am

1 stop15h 23m

Decatur Arpt

Tue 10/7

9:38 am-2:27 pm

1 stop4h 49m

$291

St. LouisDecatur

STL - DEC

STLDEC

Lambert-St Louis

Mon 10/27

5:24 pm-5:52 pm

1 stop24h 28m

Decatur Arpt

Mon 11/3

7:08 pm-3:47 pm

1 stop20h 39m

$324

St. LouisDecatur

STL - DEC

STLDEC

Lambert-St Louis

Mon 9/29

12:25 pm-6:04 pm

1 stop5h 39m

Decatur Arpt

Fri 10/3

6:55 pm-6:17 pm

1 stop23h 22m

$496

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/11

Best time to book a flight from St. Louis to Decatur

Have a flexible travel schedule? Discover the best time to fly to Decatur from St. Louis with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Related info for your journey

Find useful and relevant information for your journey from St. Louis to Decatur. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • How long is the flight from St. Louis to Decatur, Illinois?

    A quick flight from St. Louis to Decatur, Illinois can take about 15h 23m. United Airlines provides one of the quickest options available for as low as $291. St. Louis and Decatur, Illinois are separated by a distance of 110 mi.

  • Can I find deals for flights from St. Louis to Decatur that include hotel bookings?

    Yes. In addition to deals on St. Louis to Decatur flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from St. Louis to Decatur?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from St. Louis to Decatur.

  • Can I find deals for business class flights from St. Louis to Decatur?

    Yes. Cheapflights offers flight deals from St. Louis to Decatur by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

See more FAQs

Traveling to a place near Decatur?

Book flights to Decatur if you plan to visit one of these locations
Mattoon
Effingham

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