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Cheap flights from St. Louis to Chicago from $45

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from St. Louis to Chicago departing on 3/28. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
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0 bags

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Cheap round-trip flights

Enter your travel dates to find the best prices.
Frontier Logo
2:09 pm - 8:23 am
STL
-
ORD
18h 14m
1 stop
Frontier Logo
5:01 am - 1:34 pm
ORD
-
STL
8h 33m
1 stop
$198Frontier
Mon, Mar 9 - Mon, Mar 16
Delta Logo
6:35 am - 1:20 pm
STL
-
ORD
6h 45m
1 stop
Delta Logo
5:59 pm - 11:58 pm
ORD
-
STL
5h 59m
1 stop
$201Delta
Thu, Mar 5 - Mon, Mar 9
Frontier Logo
3:49 pm - 11:15 pm
STL
-
ORD
7h 26m
1 stop
Frontier Logo
3:11 pm - 12:27 am
ORD
-
STL
9h 16m
1 stop
$202Frontier
Mon, Feb 23 - Fri, Feb 27
Multiple Airlines Logo
8:20 pm - 10:46 am
STL
-
ORD
14h 26m
1 stop
Multiple Airlines Logo
7:23 pm - 6:51 am
ORD
-
STL
35h 28m
2 stops
$203Multiple Airlines
Fri, Feb 20 - Mon, Feb 23
Delta Logo
10:50 am - 4:18 pm
STL
-
ORD
5h 28m
1 stop
Delta Logo
7:00 am - 4:49 pm
ORD
-
STL
9h 49m
2 stops
$206Delta
Sat, Apr 11 - Sat, May 9
Multiple Airlines Logo
8:12 pm - 9:43 am
STL
-
ORD
13h 31m
1 stop
Multiple Airlines Logo
6:01 pm - 10:30 am
ORD
-
STL
16h 29m
2 stops
$207Multiple Airlines
Wed, Mar 25 - Wed, Apr 1
American Airlines Logo
5:46 am - 7:16 am
STL
-
ORD
1h 30mnonstop
American Airlines Logo
6:59 am - 8:24 am
ORD
-
STL
1h 25mnonstop
$208American Airlines
Sat, Apr 11 - Sun, Apr 12
Frontier Logo
8:13 pm - 10:44 am
STL
-
ORD
14h 31m
1 stop
Frontier Logo
4:28 pm - 10:30 am
ORD
-
STL
18h 02m
1 stop
$209Frontier
Fri, Apr 17 - Wed, Apr 22
American Airlines Logo
9:15 am - 4:21 pm
STL
-
ORD
7h 06m
1 stop
American Airlines Logo
4:40 pm - 5:53 pm
ORD
-
STL
1h 13mnonstop
$211American Airlines
Mon, Mar 9 - Thu, Mar 12
Multiple Airlines Logo
8:12 pm - 9:43 am
STL
-
ORD
13h 31m
1 stop
Multiple Airlines Logo
6:01 pm - 10:32 am
ORD
-
STL
16h 31m
2 stops
$212Multiple Airlines
Sat, Mar 21 - Mon, Mar 23

Frontier flights from St. Louis to Chicago O'Hare Intl Airport

Our best Frontier deals on St. Louis to Chicago O'Hare Intl Airport flight tickets
Frontier
Mar 9
STL2:09 pmLambert-St Louis
18h 14m
1 stop
ORD8:23 amChicago O'Hare Intl
Mar 16
ORD5:01 amChicago O'Hare Intl
8h 33m
1 stop
STL1:34 pmLambert-St Louis
$198
Frontier
Feb 23
STL3:49 pmLambert-St Louis
7h 26m
1 stop
ORD11:15 pmChicago O'Hare Intl
Feb 27
ORD3:11 pmChicago O'Hare Intl
9h 16m
1 stop
STL12:27 amLambert-St Louis
$202
Frontier
Apr 17
STL8:13 pmLambert-St Louis
14h 31m
1 stop
ORD10:44 amChicago O'Hare Intl
Apr 22
ORD4:28 pmChicago O'Hare Intl
18h 02m
1 stop
STL10:30 amLambert-St Louis
$209

Delta flights from St. Louis to Chicago O'Hare Intl Airport

Our best Delta deals on St. Louis to Chicago O'Hare Intl Airport flight tickets
Delta
Mar 5
STL6:35 amLambert-St Louis
6h 45m
1 stop
ORD1:20 pmChicago O'Hare Intl
Mar 9
ORD5:59 pmChicago O'Hare Intl
5h 59m
1 stop
STL11:58 pmLambert-St Louis
$201
Delta
May 3
STL1:45 pmLambert-St Louis
6h 55m
1 stop
ORD8:40 pmChicago O'Hare Intl
May 4
ORD5:04 pmChicago O'Hare Intl
6h 09m
2 stops
STL11:13 pmLambert-St Louis
$269
Delta
Feb 24
STL11:23 amLambert-St Louis
9h 21m
2 stops
ORD8:44 pmChicago O'Hare Intl
Feb 28
ORD2:05 pmChicago O'Hare Intl
9h 18m
2 stops
STL11:23 pmLambert-St Louis
$478

momondo Fare Finder

 
Customize your flight search to find flights from St. Louis to Chicago O'Hare Intl Airport 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, momondo users made 832,500 searches. Data last updated February 10, 2026.
Use the filters below to find and compare flights from St. Louis to Chicago O'Hare Intl Airport that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

St. LouisChicago

STL - ORD

STLORD

Lambert-St Louis

Mon 3/9

2:09 pm-8:23 am

1 stop18h 14m

Chicago O'Hare Intl

Mon 3/16

5:01 am-1:34 pm

1 stop8h 33m

$198

St. LouisChicago

STL - ORD

STLORD

Lambert-St Louis

Thu 3/5

6:35 am-1:20 pm

1 stop6h 45m

Chicago O'Hare Intl

Mon 3/9

5:59 pm-11:58 pm

1 stop5h 59m

$201

St. LouisChicago

STL - ORD

STLORD

Lambert-St Louis

Mon 2/23

3:49 pm-11:15 pm

1 stop7h 26m

Chicago O'Hare Intl

Fri 2/27

3:11 pm-12:27 am

1 stop9h 16m

$202

St. LouisChicago

STL - ORD

STLORD

Lambert-St Louis

Fri 2/20

8:20 pm-10:46 am

1 stop14h 26m

Chicago O'Hare Intl

Mon 2/23

7:23 pm-6:51 am

2 stops35h 28m

$203

St. LouisChicago

STL - ORD

STLORD

Lambert-St Louis

Sat 4/11

10:50 am-4:18 pm

1 stop5h 28m

Chicago O'Hare Intl

Sat 5/9

7:00 am-4:49 pm

2 stops9h 49m

$206

St. LouisChicago

STL - ORD

STLORD

Lambert-St Louis

Wed 3/25

8:12 pm-9:43 am

1 stop13h 31m

Chicago O'Hare Intl

Wed 4/1

6:01 pm-10:30 am

2 stops16h 29m

$207

St. LouisChicago

STL - ORD

STLORD

Lambert-St Louis

Sat 4/11

5:46 am-7:16 am

Nonstop1h 30m

Chicago O'Hare Intl

Sun 4/12

6:59 am-8:24 am

Nonstop1h 25m

$208

St. LouisChicago

STL - ORD

STLORD

Lambert-St Louis

Fri 4/17

8:13 pm-10:44 am

1 stop14h 31m

Chicago O'Hare Intl

Wed 4/22

4:28 pm-10:30 am

1 stop18h 02m

$209

St. LouisChicago

STL - ORD

STLORD

Lambert-St Louis

Mon 3/9

9:15 am-4:21 pm

1 stop7h 06m

Chicago O'Hare Intl

Thu 3/12

4:40 pm-5:53 pm

Nonstop1h 13m

$211

St. LouisChicago

STL - ORD

STLORD

Lambert-St Louis

Sat 3/21

8:12 pm-9:43 am

1 stop13h 31m

Chicago O'Hare Intl

Mon 3/23

6:01 pm-10:32 am

2 stops16h 31m

$212

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 20 resultsSorted by cheapest first
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See travel insights to Chicago from

How to get the cheapest flight ticket from St. Louis to Chicago O'Hare Intl Airport

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

What is the cheapest month to fly to Chicago O'Hare Intl Airport?

The month of April is another great option to travel to Chicago O'Hare Intl Airport, with average flight prices from St. Louis averaging around $236.

What is the cheapest day to depart on your flight to Chicago O'Hare Intl Airport?

The cheapest day to depart on your flight to Chicago O'Hare Intl Airport is on a Friday when prices can be found for as low as $745. This is often the case because there is less demand to fly during this day of the week. On the other hand, Wednesday is the most expensive day to depart from St. Louis because it is more convenient for both business and leisure travelers. As a result, prices tend to be around $912.

What is the cheapest time of day to depart on your flight to Chicago O'Hare Intl Airport?

Flying to Chicago O'Hare Intl Airport from St. Louis in the morning is the least expensive time of day to depart. momondo users have found prices as low as $631 when looking at flights departing in the morning. Try not to purchase tickets at noon because they tend to be around $1,177. Of course, these prices can vary depending on the time of year and what airport you fly to.

What is the cheapest Lambert-St Louis to Chicago O'Hare Intl flight route?

Fly from Lambert-St Louis to Chicago O'Hare Intl for the best Lambert-St Louis - Chicago O'Hare Intl flight prices

How far in advance should I book a flight to Chicago O'Hare Intl Airport?

You are more likely to see cheaper flights to Chicago O'Hare Intl Airport from St. Louis when booking weeks ahead of your departure date. In general, you can expect to find flights to Chicago O'Hare Intl Airport for around $290 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Chicago O'Hare Intl Airport from St. Louis for as low as $168 on momondo.

What cabin class options are available on Lambert-St Louis to Chicago O'Hare Intl flights?

There are 4 cabin classes available to choose from on Lambert-St Louis to Chicago O'Hare Intl flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

How have St. Louis to Chicago O'Hare Intl Airport flight prices changed over time?

As of February 2026, prices for St. Louis to Chicago O'Hare Intl Airport flights are approximately 30% more expensive when compared to flights at the same time last year.

When to book flights from St. Louis to Chicago O'Hare Intl Airport

Are you open to changing your travel dates? Check out the ideal times to fly from St. Louis to Chicago O'Hare Intl Airport according to our flight data. Find out which month and days have the cheapest flights.
Estimated round-trip price

Cheap St. Louis to Chicago O'Hare Intl Airport (STL to ORD) flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from St. Louis to Chicago O'Hare Intl Airport

Best Price Found

$229

Fastest flight time

1h 26m

Direct flights

Every day
The best one-way flight to Chicago O'Hare Intl Airport from St. Louis in the past 72 hours is $229. The best round-trip flight deal from St. Louis to Chicago O'Hare Intl Airport found on momondo in the last 72 hours is $470.
The fastest flight from St. Louis to Chicago O'Hare Intl Airport takes 1h 26m
Direct flights go from St. Louis to Chicago O'Hare Intl Airport every day.
Search flight deals

  • How far is Lambert-St Louis to Chicago O'Hare Intl by plane?

    Lambert-St Louis and Chicago O'Hare Intl are 261.0 mi apart from one another. Typically, this will take 1h 26m by plane in normal conditions.

  • When did momondo last update prices for flights from Lambert-St Louis Airport to Chicago O'Hare Intl Airport?

    Prices for flights from Lambert-St Louis Airport to Chicago O'Hare Intl Airport are refreshed on a daily basis.

  • How many operators does momondo search for flights from Lambert-St Louis Airport to Chicago O'Hare Intl Airport?

  • How old do you have to be to fly from Lambert-St Louis Airport to Chicago O'Hare Intl Airport?

    Although the minimum age for a child to fly alone is five, airlines that offer an unaccompanied minor (UMNR) service may have their own age limits, which could be impacted by factors such as flight length, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Lambert-St Louis Airport to Chicago O'Hare Intl Airport.

  • What documentation or ID do you need to fly to Chicago O'Hare Intl Airport?

    The travel and health documents you'll need for your trip to Chicago O'Hare Intl Airport may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's license and a passport that is valid for six months after your intended arrival at Chicago O'Hare Intl Airport. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.

  • What is the most popular plane model from St. Louis to Chicago O'Hare Intl Airport?

  • What is the most popular airline from St. Louis to Chicago O'Hare Intl Airport?

Best airlines flying from St. Louis to Chicago O'Hare Intl Airport

Compare and see reviews for airlines that fly from St. Louis to Chicago O'Hare Intl Airport with momondo
Airline
Rating
Free Cancellation
Price
American AirlinesPriceFrom $97Free CancellationRating
7.2
11,261 reviews
Search American Airlines flights
United AirlinesPriceFrom $114Free CancellationRating
7.4
9,268 reviews
Search United Airlines flights
Southern / MokulelePriceFrom $140Free CancellationRating
0.0
0 reviews
Search Southern / Mokulele flights

  • United Airlines Flights From St. Louis to Chicago O'Hare Intl Airport

    The lowest priced United Airlines flight from St. Louis to Chicago O'Hare Intl Airport from the last 72 hours was $114. Generally, United Airlines has 21 flights on this route every week with an average price of $330. United Airlines is rated 7.4/10 by our users.

  • American Airlines Flights From St. Louis to Chicago O'Hare Intl Airport

    American Airlines is also a popular choice for this route. American Airlines flight deals for St. Louis to Chicago O'Hare Intl Airport start from as low as $97 round-trip, depending on your selected dates, with average American Airlines deals seen on momondo around $293. American Airlines operates 12 flights to Chicago O'Hare Intl Airport from St. Louis in an average week. Users have rated it 7.2/10 across 11,261 reviews.

Traveling to a place near Chicago?

Book flights to Chicago if you plan to visit one of these locations
Lake Geneva
Schaumburg
South Haven
Rockford
Merrillville
Gurnee
Naperville
Rosemont
New Buffalo
Kenosha
Oak Brook
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Orland Park
Racine
Hammond
Janesville
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Elgin
Aurora
South Holland

Why use momondo?

Why should I use momondo to find a flight deal from St. Louis to Chicago?

To find the flight that best suits your needs, momondo gathers a range of flights from a large pool of different airlines and agents; you can then use our insights and filters to find and book the right flight to Chicago from St. Louis.

Can I find flights from St. Louis to Chicago with flexible booking policies on momondo?

Yes. All flights to Chicago from St. Louis on momondo can be compared and filtered by various policies on offer, including flexible booking.

How can momondo help me find flights from St. Louis to Chicago?

Once all potential St. Louis to Chicago flight options are in front of you, momondo lets you sort and filter flights based on preferences such as airline, price and flight times amongst many other options.

I’m not ready to book a flight from St. Louis to Chicago right now. Can momondo alert me if prices change?

Of course. momondo tracks the price of St. Louis to Chicago flights. All you need is a valid email address and we will do the rest; it is that quick and easy.

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