$350+ Cheap flights from Decatur, IL to St. Louis (DEC - STL)
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 10/8. Fares are subject to change and may not be available on all flights or dates of travel.
DEC — STL
Oct 12 — Oct 191
Round-trip
1 adult, Economy
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Find cheap flights from Decatur to St. Louis with Cheapflights
1. Tell us where you want to go
Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”2. Select your favorite providers
We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.3. Compare prices and book
Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.Cheap flight deals from Decatur to St. Louis
Cheapest
Best
Last-minute
Cheapest flights from Decatur to St. LouisExplore the most affordable flight options available from Decatur to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 12, 2026.
Explore the most affordable flight options available from Decatur to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 12, 2026.
This United Airlines deal was found by Cheapflights users on 9/10. 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.
Thu 10/89:12 am -
1 stop12h 09m
Thu 10/156:00 am -
1 stop11h 53m
Deal found 9/10![United Airlines logo]()
$350
This United Airlines deal was found by Cheapflights users on 9/9. 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 9/259:12 am -
1 stop6h 31m
Tue 9/291:29 pm -
1 stop5h 14m
Deal found 9/9![United Airlines logo]()
$394
This United Airlines deal was found by Cheapflights users on 9/9. 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.
Thu 9/179:12 am -
1 stop6h 26m
Sun 9/2012:59 pm -
1 stop5h 45m
Deal found 9/9![United Airlines logo]()
$404
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.
Sun 9/277:18 pm -
1 stop3h 41m
Thu 10/11:29 pm -
1 stop4h 24m
Deal found 9/11![United Airlines logo]()
$632
This United Airlines deal was found by Cheapflights users on 9/9. 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.
Thu 9/247:18 pm -
1 stop21h 43m
Mon 9/281:29 pm -
1 stop5h 14m
Deal found 9/9![United Airlines logo]()
$776
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.
Mon 10/127:18 pm -
1 stop21h 43m
Mon 10/199:04 am -
1 stop9h 39m
Deal found 9/11![United Airlines logo]()
$836
Best flights from Decatur to St. LouisDiscover carefully curated flight deals from Decatur to St. Louis that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated September 12, 2026.
Discover carefully curated flight deals from Decatur to St. Louis that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated September 12, 2026.
This United Airlines deal was found by Cheapflights users on 9/9. 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 9/259:12 am -
1 stop6h 31m
Tue 9/291:29 pm -
1 stop5h 14m
Deal found 9/9![United Airlines logo]()
$394
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 9/267:18 pm -
1 stop3h 41m
Wed 9/301:29 pm -
1 stop5h 14m
Deal found 9/11![United Airlines logo]()
$404
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.
Sun 9/277:18 pm -
1 stop3h 41m
Thu 10/11:29 pm -
1 stop4h 24m
Deal found 9/11![United Airlines logo]()
$632
This United Airlines deal was found by Cheapflights users on 9/9. 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.
Thu 9/247:18 pm -
1 stop21h 43m
Mon 9/281:29 pm -
1 stop5h 14m
Deal found 9/9![United Airlines logo]()
$776
This United Airlines deal was found by Cheapflights users on 9/10. 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.
Thu 10/87:18 pm -
1 stop24h 23m
Thu 10/159:04 am -
1 stop8h 49m
Deal found 9/10![United Airlines logo]()
$816
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.
Mon 10/127:18 pm -
1 stop21h 43m
Mon 10/199:04 am -
1 stop9h 39m
Deal found 9/11![United Airlines logo]()
$836
Last-minute flights from Decatur to St. LouisDiscover last-minute flight deals from Decatur to St. Louis. Data last updated September 12, 2026 and is based on user searches.
Discover last-minute flight deals from Decatur to St. Louis. Data last updated September 12, 2026 and is based on user searches.
This United Airlines deal was found by Cheapflights users on 9/9. 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.
Thu 9/179:12 am -
1 stop6h 26m
Sun 9/2012:59 pm -
1 stop5h 45m
Deal found 9/9![United Airlines logo]()
$404
This United Airlines deal was found by Cheapflights users on 9/9. 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.
Thu 9/247:18 pm -
1 stop21h 43m
Mon 9/281:29 pm -
1 stop5h 14m
Deal found 9/9![United Airlines logo]()
$776
This United Airlines deal was found by Cheapflights users on 9/9. 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 9/259:12 am -
1 stop6h 31m
Tue 9/291:29 pm -
1 stop5h 14m
Deal found 9/9![United Airlines logo]()
$394
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.
Sun 9/277:18 pm -
1 stop3h 41m
Thu 10/11:29 pm -
1 stop4h 24m
Deal found 9/11![United Airlines logo]()
$632
This United Airlines deal was found by Cheapflights users on 9/10. 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.
Thu 10/89:12 am -
1 stop12h 09m
Thu 10/156:00 am -
1 stop11h 53m
Deal found 9/10![United Airlines logo]()
$350
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.
Mon 10/127:18 pm -
1 stop21h 43m
Mon 10/199:04 am -
1 stop9h 39m
Deal found 9/11![United Airlines logo]()
$836
Find flight deals from Decatur to St. Louis
Discover tips and strategies to find the most affordable flight options for your journey from Decatur (DEC) to St. Louis (STL). 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 12, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $350 (United Airlines) |
Cheapflights Fare Finder
Customize your flight search to find flights from Decatur to St. Louis 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 7,457,451 searches. Data last updated September 12, 2026.
Use the filters below to find and compare flights from Decatur to St. Louis that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
DecaturSt. Louis
DEC Decatur Arpt - STL Lambert-St Louis
DECSTL
Decatur Arpt
Fri 9/25
9:12 am-3:43 pm
1 stop6h 31m
Lambert-St Louis
Tue 9/29
1:29 pm-6:43 pm
1 stop5h 14m
$394
DecaturSt. Louis
DEC Decatur Arpt - STL Lambert-St Louis
DECSTL
Decatur Arpt
Sat 9/26
7:18 pm-10:59 pm
1 stop3h 41m
Lambert-St Louis
Wed 9/30
1:29 pm-6:43 pm
1 stop5h 14m
$404
Quickest round-trip
DecaturSt. Louis
DEC Decatur Arpt - STL Lambert-St Louis
DECSTL
Decatur Arpt
Sun 9/27
7:18 pm-10:59 pm
1 stop3h 41m
Lambert-St Louis
Thu 10/1
1:29 pm-5:53 pm
1 stop4h 24m
$632
DecaturSt. Louis
DEC Decatur Arpt - STL Lambert-St Louis
DECSTL
Decatur Arpt
Thu 9/24
7:18 pm-5:01 pm
1 stop21h 43m
Lambert-St Louis
Mon 9/28
1:29 pm-6:43 pm
1 stop5h 14m
$776
DecaturSt. Louis
DEC Decatur Arpt - STL Lambert-St Louis
DECSTL
Decatur Arpt
Thu 10/8
7:18 pm-7:41 pm
1 stop24h 23m
Lambert-St Louis
Thu 10/15
9:04 am-5:53 pm
1 stop8h 49m
$816
DecaturSt. Louis
DEC Decatur Arpt - STL Lambert-St Louis
DECSTL
Decatur Arpt
Mon 10/12
7:18 pm-5:01 pm
1 stop21h 43m
Lambert-St Louis
Mon 10/19
9:04 am-6:43 pm
1 stop9h 39m
$836
Sorted by cheapest first
Compare providers for flights from Decatur to St. Louis
Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Decatur to St. Louis in September.
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars |
- Most accurate provider: When it comes to deals on Decatur, Illinois-St. Louis flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Decatur, Illinois-St. Louis flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Decatur, Illinois-St. Louis flight searches over the past month and is updated monthly.
- Most trusted provider: When it comes to deals on Decatur, Illinois-St. Louis flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Decatur, Illinois-St. Louis flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.
Best time to book a flight from Decatur to St. Louis
Have a flexible travel schedule? Discover the best time to fly to St. Louis from Decatur with our price prediction graph.
DEC-STL
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 Decatur to St. Louis. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
Traveling to a place near St. Louis?
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