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.

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.

$286+ Flights from St. Louis to Decatur, IL

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Cheap flight deals from St. Louis to Decatur

Round-trip from	$286 (United Airlines)

From Lambert-St Louis to Decatur Arpt

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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 julio 29, 2025.

sáb. 10/412:25 pmSTL - DEC

1 stop20h 26mUnited Airlines

mar. 10/79:38 amDEC - STL

1 stop4h 49mUnited Airlines

Deal found 7/26

$286

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 julio 29, 2025.

sáb. 10/412:25 pmSTL - DEC

1 stop20h 26mUnited Airlines

mar. 10/79:38 amDEC - STL

1 stop4h 49mUnited Airlines

Deal found 7/26

$286

Last-minute flights from St. Louis to Decatur
Discover last-minute flight deals from St. Louis to Decatur. Data last updated julio 29, 2025 and is based on user searches.

mar. 8/125:00 amSTL - DEC

1 stop3h 48mUnited Airlines

sáb. 8/169:45 amDEC - STL

1 stop13h 00mUnited Airlines

Deal found 7/28

$442

Fly from

Fly to

Route

Depart

Return

Price

St. LouisDecatur

STL - DEC

STLDEC

Lambert-St Louis

sáb. 10/4

12:25 pm-8:51 am

1 stop20h 26m

Decatur Arpt

mar. 10/7

9:38 am-2:27 pm

1 stop4h 49m

$286

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/26

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.

Reviews of airlines servicing Decatur

See what other customers who have flown with United Airlines from St. Louis to Decatur have to say. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.

United Airlines

7.4

Good

8,899 reviews

Reviews

1 / 20

2.0

Mediocre

Deb,Jan 2025

MKE - ORD

It was terrible! So much to say, but in a nutshell we used vouchers from United because our last trip with them was awful with many mishaps and errors made. Unfortunately, this trip was even worse!

United Airlines

7.4

Good

8,899 reviews

United Airlines

7.4

Good

8,899 reviews

Reviews

1 / 20

2.0

Mediocre

Deb,Jan 2025

MKE - ORD

It was terrible! So much to say, but in a nutshell we used vouchers from United because our last trip with them was awful with many mishaps and errors made. Unfortunately, this trip was even worse!

Related info for your journey

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.

Mattoon

Effingham

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$286+ 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.

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

Round-trip from

Find 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 julio 29, 2025.

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 julio 29, 2025.

Cheapflights Fare Finder

Use the filters below to find and compare flights from St. Louis to Decatur that are best for you.

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.

Reviews of airlines servicing Decatur

See what other customers who have flown with United Airlines from St. Louis to Decatur have to say. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.

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.

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?

Traveling to a place near 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 julio 29, 2025.