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

A quick flight from St. Louis to Decatur, Illinois can take about 7h 59m. United Airlines provides one of the quickest options available for as low as $406. St. Louis and Decatur, Illinois are separated by a distance of 110 mi.

In terms of precipitation, rainfall in Decatur, Illinois ranges from 1.7 - 4.4 inches per month. June is typically the wettest month, when rainfall can reach 4.4 in. January is typically the driest time to visit Decatur, Illinois when rainfall is around 1.7 in.

If weather is an important factor for your trip to Decatur, Illinois, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 75.2 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 26.6 F).

What is the cheapest time of day to fly from STL to DEC?

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from St. Louis to Decatur, Illinois as you normally would.

Most accurate provider : When it comes to deals on St. Louis-Decatur, Illinois flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on St. Louis-Decatur, Illinois flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from St. Louis-Decatur, Illinois flight searches over the past month and is updated monthly.

Most trusted provider : When it comes to deals on St. Louis-Decatur, Illinois 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 St. Louis-Decatur, Illinois flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

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.

$406+ Flights from St. Louis to Decatur, IL

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Cheap 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 January 28, 2026.

Thu 2/129:55 am

STL

DEC

1 stop7h 59m

United Airlines

Mon 2/167:15 pm

DEC

STL

1 stop25h 50m

United Airlines

Deal found 1/27

$406

Fri 3/137:00 pm

STL

DEC

1 stop22h 53m

United Airlines

Fri 3/207:15 pm

DEC

STL

1 stop26h 27m

United Airlines

Deal found 1/27

$535

Best flights from St. Louis to Decatur
Discover carefully curated flight deals from St. Louis to Decatur that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated January 28, 2026.

Thu 2/129:55 am

STL

DEC

1 stop7h 59m

United Airlines

Mon 2/167:15 pm

DEC

STL

1 stop25h 50m

United Airlines

Deal found 1/27

$406

Fri 3/137:00 pm

STL

DEC

1 stop22h 53m

United Airlines

Fri 3/207:15 pm

DEC

STL

1 stop26h 27m

United Airlines

Deal found 1/27

$535

Last-minute flights from St. Louis to Decatur
Discover last-minute flight deals from St. Louis to Decatur. Data last updated January 28, 2026 and is based on user searches.

Thu 2/129:55 am

STL

DEC

1 stop7h 59m

United Airlines

Mon 2/167:15 pm

DEC

STL

1 stop25h 50m

United Airlines

Deal found 1/27

$406

Find flight deals from St. Louis to Decatur

Most accurate provider	FlightHub 3 stars
Most trusted provider	FlightHub 3 stars
Round-trip from	$406 (United Airlines)

Provider with most accurate pricing for Lambert-St Louis-Decatur Arpt flight deals.

Search Deals

Provider most trusted by Cheapflights users for Lambert-St Louis-Decatur Arpt flights.

Search Deals

From Lambert-St Louis to Decatur Arpt

Search Deals

Fly from

Fly to

Route

Depart

Return

Price

St. LouisDecatur

STL - DEC

STLDEC

Lambert-St Louis

Thu 2/12

9:55 am-5:54 pm

1 stop7h 59m

Decatur Arpt

Mon 2/16

7:15 pm-9:05 pm

1 stop25h 50m

$406

St. LouisDecatur

STL - DEC

STLDEC

Lambert-St Louis

Fri 3/13

7:00 pm-5:53 pm

1 stop22h 53m

Decatur Arpt

Fri 3/20

7:15 pm-9:42 pm

1 stop26h 27m

$535

Flights are sorted by cheapest round-trip flights first.

Deals found on 1/27

Most accurate provider: When it comes to deals on St. Louis-Decatur, Illinois flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on St. Louis-Decatur, Illinois flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from St. Louis-Decatur, Illinois flight searches over the past month and is updated monthly.
Most trusted provider: When it comes to deals on St. Louis-Decatur, Illinois 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 St. Louis-Decatur, Illinois 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 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

How long is the flight from St. Louis to Decatur, Illinois?
A quick flight from St. Louis to Decatur, Illinois can take about 7h 59m. United Airlines provides one of the quickest options available for as low as $406. 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.

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$406+ 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 2/12. Fares are subject to change and may not be available on all flights or dates of travel.

Find cheap flights from St. Louis to Decatur with Cheapflights

1. Tell us where you want to go

2. Select your favorite providers

3. Compare prices and book

Cheap flight deals from St. Louis to Decatur

Cheapest flights from St. Louis to DecaturExplore 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 January 28, 2026.

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 January 28, 2026.

Find flight deals from St. Louis to Decatur

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Most trusted provider

Round-trip from

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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.

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?

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

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

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

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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 January 28, 2026.