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St. Louis

$46+ Cheap flights from Chicago (CHI) to St. Louis (STL)

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 8/27. Fares are subject to change and may not be available on all flights or dates of travel.
CHI — STL
août 2 — août 91
sam. 8/2
sam. 8/9
1 adult, Economy
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Cheapflights Tip: The best prices from Chicago to Lambert-St Louis are usually found in September or August, booked 78 days in advance, depart on a Thursday or Friday and return on a Thursday

Cheap flight deals from Chicago to St. Louis

Discover tips and strategies to find the most affordable flight options for your journey from Chicago (CHI) 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 juillet 28, 2025.

Round-trip from

$90
(American Airlines)

One-way from

$46
(Southwest)

Popular in

July

Cheapest in

September

Average price

$361

Good round-trip deal

$151 or less

Good one-way deal

$87 or less
From Chicago (CHI) to Lambert-St Louis
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One-way flight from Chicago (CHI) to Lambert-St Louis
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Highest demand for flights based on searches. 1% potential increase in price ($2 potential increase over avg. RT price).
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Cheapest flight prices on average. 2% potential price decrease ($7 potential savings vs. average RT price).
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Average for round-trip flights in July 2025
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Price to beat on a round-trip flight from Chicago (CHI) to Lambert-St Louis.
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Price to beat on a one-way flight from Chicago (CHI) to Lambert-St Louis.
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Find flight deals from Chicago to St. Louis

Cheapest flights from Chicago to St. Louis
Explore the most affordable flight options available from Chicago to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on juillet 28, 2025.

This American Airlines deal was found by Cheapflights users on 7/26. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sam. 9/207:10 pmORD - STL
Nonstop1h 22mAmerican Airlines
sam. 10/47:23 amSTL - ORD
Nonstop1h 22mAmerican Airlines
Deal found 7/26$90
This Southwest deal was found by Cheapflights users on 7/28. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sam. 9/206:35 amMDW - STL
Nonstop1h 10mSouthwest
sam. 10/45:55 pmSTL - MDW
Nonstop1h 10mSouthwest
Deal found 7/28$91
This United Airlines deal was found by Cheapflights users on 7/26. 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.
sam. 8/232:20 pmORD - STL
Nonstop1h 24mUnited Airlines
sam. 8/305:30 pmSTL - ORD
Nonstop1h 25mUnited Airlines
Deal found 7/26$91
This Southwest deal was found by Cheapflights users on 7/26. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ven. 8/222:55 pmORD - STL
1 stop4h 15mSouthwest
lun. 8/255:30 amSTL - ORD
1 stop7h 15mSouthwest
Deal found 7/26$134
This Kissandfly.com deal was found by Cheapflights users on 7/26. 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 Kissandfly.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sam. 8/166:55 amORD - STL
Nonstop1h 25mSouthern / Mokulele
dim. 8/175:15 pmSTL - ORD
1 stop3h 37mSouthern / Mokulele
Deal found 7/26$136
This eDestinos deal was found by Cheapflights users on 7/26. 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 eDestinos is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 9/97:20 amORD - STL
1 stop25h 46mFrontier
mar. 9/167:55 pmSTL - ORD
1 stop25h 33mFrontier
Deal found 7/26$161
This Delta deal was found by Cheapflights users on 7/26. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 9/94:25 pmMDW - STL
1 stop5h 37mDelta
mar. 9/166:40 amSTL - MDW
1 stop5h 48mDelta
Deal found 7/26$177
This Delta deal was found by Cheapflights users on 7/28. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 8/261:30 pmORD - STL
1 stop5h 37mDelta
dim. 8/315:11 pmSTL - ORD
1 stop6h 45mDelta
Deal found 7/28$177
This Frontier deal was found by Cheapflights users on 7/25. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
jeu. 8/76:20 amMDW - STL
1 stop7h 14mFrontier
sam. 8/92:52 pmSTL - MDW
1 stop7h 41mFrontier
Deal found 7/25$188
This FlightHub deal was found by Cheapflights users on 7/27. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 8/111:10 pmORD - STL
1 stop3h 35mMultiple Airlines
mar. 8/125:40 pmSTL - ORD
1 stop16h 34mMultiple Airlines
Deal found 7/27$206

Cheapflights Fare Finder

 
Customize your flight search to find flights from Chicago 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 2,558,603 searches. Data last updated juillet 28, 2025.
Use the filters below to find and compare flights from Chicago to St. Louis that are best for you.

Fly from

Chicago

Fly to

St. Louis

Route

Depart

Return

Price

ChicagoSt. Louis

ORD - STL

ORDSTL

Chicago O'Hare Intl

sam. 9/20

7:10 pm-8:32 pm

Nonstop1h 22m

Lambert-St Louis

sam. 10/4

7:23 am-8:45 am

Nonstop1h 22m

$90

ChicagoSt. Louis

MDW - STL

MDWSTL

Chicago Midway

sam. 9/20

6:35 am-7:45 am

Nonstop1h 10m

Lambert-St Louis

sam. 10/4

5:55 pm-7:05 pm

Nonstop1h 10m

$91

ChicagoSt. Louis

ORD - STL

ORDSTL

Chicago O'Hare Intl

sam. 8/23

2:20 pm-3:44 pm

Nonstop1h 24m

Lambert-St Louis

sam. 8/30

5:30 pm-6:55 pm

Nonstop1h 25m

$91

ChicagoSt. Louis

ORD - STL

ORDSTL

Chicago O'Hare Intl

ven. 8/22

2:55 pm-7:10 pm

1 stop4h 15m

Lambert-St Louis

lun. 8/25

5:30 am-12:45 pm

1 stop7h 15m

$134

ChicagoSt. Louis

ORD - STL

ORDSTL

Chicago O'Hare Intl

sam. 8/16

6:55 am-8:20 am

Nonstop1h 25m

Lambert-St Louis

dim. 8/17

5:15 pm-8:52 pm

1 stop3h 37m

$136

ChicagoSt. Louis

ORD - STL

ORDSTL

Chicago O'Hare Intl

mar. 9/9

7:20 am-9:06 am

1 stop25h 46m

Lambert-St Louis

mar. 9/16

7:55 pm-9:28 pm

1 stop25h 33m

$161

ChicagoSt. Louis

MDW - STL

MDWSTL

Chicago Midway

mar. 9/9

4:25 pm-10:02 pm

1 stop5h 37m

Lambert-St Louis

mar. 9/16

6:40 am-12:28 pm

1 stop5h 48m

$177

ChicagoSt. Louis

ORD - STL

ORDSTL

Chicago O'Hare Intl

mar. 8/26

1:30 pm-7:07 pm

1 stop5h 37m

Lambert-St Louis

dim. 8/31

5:11 pm-11:56 pm

1 stop6h 45m

$177

ChicagoSt. Louis

MDW - STL

MDWSTL

Chicago Midway

jeu. 8/7

6:20 am-1:34 pm

1 stop7h 14m

Lambert-St Louis

sam. 8/9

2:52 pm-10:33 pm

1 stop7h 41m

$188

ChicagoSt. Louis

ORD - STL

ORDSTL

Chicago O'Hare Intl

jeu. 9/11

8:15 am-4:35 pm

1 stop8h 20m

Lambert-St Louis

jeu. 9/18

7:04 pm-8:36 pm

Nonstop1h 32m

$200

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/28

Showing 1-10 of 22 results
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The best insider tips for Chicago to St. Louis flights

Snippets provided in this section are AI-generated based on a summarization of Cheapflights-commissioned articles. The articles are presented as-is, for general informational purposes only, and may not be up-to-date. The opinions contained in the articles are original to the author and reflect their authentic experience, which may vary significantly from the experience of others.
Cheapflights partnered with top experts to bring you the best recommendations for your Chicago to St. Louis trip
Airports
ORD

Avoid traffic delays by taking the 'L' train to ORD, a reliable option from downtown Chicago.

Read more about ORDby Ramsey Qubein
MDW

Use the 'L' train for a quick, affordable trip to MDW, taking less than 30 minutes from the city center.

Read more about MDWby Ramsey Qubein
STL

Take the MetroLink from STL for a convenient, affordable ride to downtown St. Louis in about 40 minutes.

Read more about STLby Taryn White
Our travel experts
Ramsey Qubein

Ramsey Qubein

Expert on ORD and MDW

Ramsey Qubein

Ramsey Qubein

An avid traveler and aviation expert who has visited 173 countries, all 50 states and seven continents, Ramsey Qubein flies nearly 400,000 miles a year. As a North Carolina-based freelance journalist for publications including Conde Nast Traveler, Forbes, USA Today and Bloomberg among others, he explores the latest trends in aviation, hospitality, cruises and business.

Read more
Taryn White

Taryn White

Expert on STL

Taryn White

Taryn White

Taryn White is a freelance travel writer, digital creator, and travel advisor who has visited nearly 100 countries and all 50 states. She’s familiar with many airports and enjoys beach hopping, boutique hotels, spa experiences, and exploring local culture. Her work has appeared in Travel + Leisure, Condé Nast Traveler, National Geographic, Smithsonian Magazine, AFAR, and more.

Read more

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

Have a flexible travel schedule? Discover the best time to fly to St. Louis from Chicago 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.

Cheapflights Insights

Everything you need to know about your flight from Chicago to St. Louis

How far ahead should I book a flight from Chicago to St. Louis?

Use this chart to determine the optimal time to book a round-trip flight from Chicago to St. Louis. Price data was last updated on July 25, 2025.

The price you pay for your flight from Chicago to St. Louis may vary depending on when you book. For the best chance of a lower fare, look to book 76 days in advance of your trip. Fares are likely to increase a fortnight or so before your departure date.

What is the cheapest month to book a flight from Chicago to St. Louis?

Currently, August is the cheapest month in which you can book a flight from Chicago to St. Louis (average of $311). Flying from Chicago to St. Louis in March is currently the most expensive (average of $356). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

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

Find hourly flight availability from Chicago to St. Louis. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated juillet 28, 2025.

Unlike in the morning, when flights are generally more expensive, you can save up to 32% on flights from Chicago to St. Louis by exploring options for tickets in the evening.

What is the cheapest day to fly from Chicago to St. Louis?

Use this chart to determine the cheapest time to fly round-trip from Chicago to St. Louis. Price data was last updated on July 27, 2025.

Travelers seeking maximum savings on their Chicago to St. Louis flight should consider departing on Wednesday evenings when fares are most often at their lowest. Monday mornings flights should be avoided if possible as fares are typically the most expensive at this time.

Weekly flight availability from Chicago to St. Louis

Explore weekly flight availability from Chicago to St. Louis. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated juillet 28, 2025.

The most flights from CHI to STL are scheduled on a Sunday (77 on average). You will have fewer flight options on Wednesday, which is when the least amount of flights are scheduled (61 on average).

How much does it cost to fly round-trip from Chicago to St. Louis?

Reviews of airlines servicing St. Louis

Get insights into the airlines that provide service to St. Louis. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to St. Louis. Reviews last updated juillet 28, 2025.
See what other customers who have flown with Southwest, Delta, and United Airlines from Chicago to St. Louis have to say. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.0
Very good
4,238 reviews

Food

7.0

Overall

8.0

Boarding

8.1

Crew

8.6

Comfort

8.0

Entertainment

7.5

Reviews

1 / 20
8.0
Excellent

Gina,Jul 2025

LAS - DEN

We experienced bad weather, which turned our 1.5 hour flight from Las Vegas to Denver, into 3.5. The pilot and crew kept us updated and explained that we had to circle and or possibly redirect to another airport. After circling for sometime, we were able to land smoothly in Denver. Thank you to all the flight crew, tower control, and all who got us to our destination safely.
Southwest
8.0
Very good
4,238 reviews
Southwest
8.0
Very good
4,238 reviews

Food

7.0

Overall

8.0

Boarding

8.1

Crew

8.6

Comfort

8.0

Entertainment

7.5

Reviews

1 / 20
8.0
Excellent

Gina,Jul 2025

LAS - DEN

We experienced bad weather, which turned our 1.5 hour flight from Las Vegas to Denver, into 3.5. The pilot and crew kept us updated and explained that we had to circle and or possibly redirect to another airport. After circling for sometime, we were able to land smoothly in Denver. Thank you to all the flight crew, tower control, and all who got us to our destination safely.
Delta
8.0
Very good
7,975 reviews
Southwest
8.0
Very good
4,238 reviews

Food

7.0

Overall

8.0

Boarding

8.1

Crew

8.6

Comfort

8.0

Entertainment

7.5

Reviews

1 / 20
8.0
Excellent

Gina,Jul 2025

LAS - DEN

We experienced bad weather, which turned our 1.5 hour flight from Las Vegas to Denver, into 3.5. The pilot and crew kept us updated and explained that we had to circle and or possibly redirect to another airport. After circling for sometime, we were able to land smoothly in Denver. Thank you to all the flight crew, tower control, and all who got us to our destination safely.
United Airlines
7.4
Good
8,892 reviews
Southwest
8.0
Very good
4,238 reviews

Food

7.0

Overall

8.0

Boarding

8.1

Crew

8.6

Comfort

8.0

Entertainment

7.5

Reviews

1 / 20
8.0
Excellent

Gina,Jul 2025

LAS - DEN

We experienced bad weather, which turned our 1.5 hour flight from Las Vegas to Denver, into 3.5. The pilot and crew kept us updated and explained that we had to circle and or possibly redirect to another airport. After circling for sometime, we were able to land smoothly in Denver. Thank you to all the flight crew, tower control, and all who got us to our destination safely.
American Airlines
7.2
Good
10,000 reviews
Southwest
8.0
Very good
4,238 reviews

Food

7.0

Overall

8.0

Boarding

8.1

Crew

8.6

Comfort

8.0

Entertainment

7.5

Reviews

1 / 20
8.0
Excellent

Gina,Jul 2025

LAS - DEN

We experienced bad weather, which turned our 1.5 hour flight from Las Vegas to Denver, into 3.5. The pilot and crew kept us updated and explained that we had to circle and or possibly redirect to another airport. After circling for sometime, we were able to land smoothly in Denver. Thank you to all the flight crew, tower control, and all who got us to our destination safely.

Related info for your journey

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

  • What airport do you fly into for flights to St. Louis from Chicago?

    If you book a flight to St. Louis from Chicago, you will be flying to Lambert-St Louis, which is the city’s only airport. Lambert-St Louis (STL) is located 12.7 mi from the center of St. Louis. There are 70 flights from Chicago to Lambert-St Louis per day from 4 different airlines.

  • What are the cheapest airlines flying from Chicago to St. Louis round-trip?

    American Airlines, at $90, was found to be the cheapest airline from Chicago to St. Louis.Alternate airlines to your destination round-trip include Southwest and United Airlines. These flights start at 69% lower than the current average price 3 months from now.

  • What are the cheapest airlines to fly from Chicago to St. Louis one-way?

    One-way options have recently been found by users for as low as $46 on Southwest. Other airlines that offer cheap prices include American Airlines from $46 and Southern / Mokulele from $85 one-way.

  • What are the most reliable airlines from Chicago to St. Louis?

    No one likes to see their flight delayed. When booking a flight from Chicago to St. Louis consider choosing Republic Airways (88%), Envoy Air (88%) or SkyWest Airlines (83%) as they are the most reliable in getting you off to your destination on time.

  • What are the cheapest flights from Chicago to St. Louis?

    The cheapest flight price from Chicago to St. Louis is $45. On average you can expect to pay $229. The most popular route, (Chicago O'Hare Intl - Lambert-St Louis), can usually be booked for $137.

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

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

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

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

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

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

  • What is the cheapest month to book a flight from Chicago to St. Louis?

    Currently, August is the cheapest month in which you can book a flight from Chicago to St. Louis (average of $311). Flying from Chicago to St. Louis in March is currently the most expensive (average of $356). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

Traveling to a place near St. Louis?

Book flights to St. Louis if you plan to visit one of these locations
O'Fallon
Maryland Heights
Fairview Heights
Collinsville
Eureka
St. Peters
Glencoe
Alton
Festus
Chesterfield
Farmington

Browse thousands of different options on Cheapflights for your next trip

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Top 4 airlines flying from Chicago to St. Louis

Discover the top 4 airlines that operate flights from Chicago to St. Louis. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated juillet 28, 2025.
AirlineCheapestAverageFlexibilityOn-time
SouthwestCheapest$77Average$328FlexibilityNo cancel feeOn-time63%
American AirlinesCheapest$115Average$283FlexibilityNo cancel feeOn-time71%
Southern / MokuleleCheapest$118Average$213FlexibilityNo cancel feeOn-timeN/A
United AirlinesCheapest$152Average$322FlexibilityNo cancel feeOn-time69%

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