$46 Cheap Flights from Chicago (ORD) to St. Louis (STL)

View $46 flight on Tue, Jul 29, 2025Opens in a new window

Popular airlines from Chicago O'Hare Intl. Airport (ORD) to St. Louis Lambert Intl. Airport (STL)

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Cheap Flights from Chicago to St. Louis (ORD-STL)

Prices were available within the past 7 days and start at $46 for one-way flights and $91 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

American Airlines
Tue, Jul 29 - Wed, Jul 30
ORD
Chicago
STL
St. Louis
$91 Roundtrip, just found
$91
Roundtrip
just found
Select American Airlines flight, departing Tue, Jul 29 from Chicago to St. Louis, returning Wed, Jul 30, priced at $91 just found
United
Thu, Oct 30 - Sat, Nov 1
ORD
Chicago
STL
St. Louis
$94 Roundtrip, just found
$94
Roundtrip
just found
Select United flight, departing Thu, Oct 30 from Chicago to St. Louis, returning Sat, Nov 1, priced at $94 just found
American Airlines
Sat, Aug 16 - Mon, Aug 18
ORD
Chicago
STL
St. Louis
$95 Roundtrip, just found
$95
Roundtrip
just found
Select American Airlines flight, departing Sat, Aug 16 from Chicago to St. Louis, returning Mon, Aug 18, priced at $95 just found
American Airlines
Thu, Sep 4 - Mon, Sep 8
ORD
Chicago
STL
St. Louis
$97 Roundtrip, just found
$97
Roundtrip
just found
Select American Airlines flight, departing Thu, Sep 4 from Chicago to St. Louis, returning Mon, Sep 8, priced at $97 just found
Southwest Airlines
Wed, Aug 13 - Sat, Aug 23
ORD
Chicago
STL
St. Louis
$101 Roundtrip, found 5 hours ago
$101
Roundtrip
found 5 hours ago
Select Southwest Airlines flight, departing Wed, Aug 13 from Chicago to St. Louis, returning Sat, Aug 23, priced at $101 found 5 hours ago
Southwest Airlines
Sat, Aug 16 - Mon, Aug 18
ORD
Chicago
STL
St. Louis
$104 Roundtrip, just found
$104
Roundtrip
just found
Select Southwest Airlines flight, departing Sat, Aug 16 from Chicago to St. Louis, returning Mon, Aug 18, priced at $104 just found
United
Tue, Aug 5 - Wed, Aug 6
ORD
Chicago
STL
St. Louis
$107 Roundtrip, found 23 hours ago
$107
Roundtrip
found 23 hours ago
Select United flight, departing Tue, Aug 5 from Chicago to St. Louis, returning Wed, Aug 6, priced at $107 found 23 hours ago
United
Wed, Nov 19 - Mon, Nov 24
ORD
Chicago
STL
St. Louis
$108 Roundtrip, found 6 days ago
$108
Roundtrip
found 6 days ago
Select United flight, departing Wed, Nov 19 from Chicago to St. Louis, returning Mon, Nov 24, priced at $108 found 6 days ago
Delta
Sat, Aug 16 - Mon, Aug 18
ORD
Chicago
STL
St. Louis
$177 Roundtrip, just found
$177
Roundtrip
just found
Select Delta flight, departing Sat, Aug 16 from Chicago to St. Louis, returning Mon, Aug 18, priced at $177 just found
Southern Airways Express
Mon, Aug 4 - Thu, Aug 7
ORD
Chicago
STL
St. Louis
$185 Roundtrip, just found
$185
Roundtrip
just found
Select Southern Airways Express flight, departing Mon, Aug 4 from Chicago to St. Louis, returning Thu, Aug 7, priced at $185 just found

Find the cheapest month to fly from Chicago (ORD) to St. Louis (STL)

September is typically the cheapest month to fly

From $93 - $272 per traveler.

Graph displaying average flight prices per month

Flights from Chicago (ORD) to St. Louis (STL)
Origin airport
O'Hare Intl.
Destination airport
Lambert-St. Louis Intl.
Airlines serving
Alaska Airlines, American Airlines, Delta, Frontier Airlines, Southern Airways Express, Southwest Airlines, United
Roundtrip price
$91
Distance
258 mi
Average flight time
1 hour 21 mins

Chicago to St. Louis Flights

The cheapest times to fly from Chicago to St. Louis

On average, Thursday can be the cheapest time to fly, according to data from the Airlines Reporting Corporation (ARC), one of the world's biggest databases for global airline sales. The data reveals that you could save up to 16% by flying on a Thursday—the cheapest day to travel on average—instead of a Sunday—the most expensive. Some of the most affordable flights from Chicago to St. Louis are during the month of July. You can find some of the cheapest flights from Chicago to St. Louis with Expedia's search tool and vast selection of airlines.

 

The best time to book a flight from Chicago to St. Louis

Sunday is one of the best days to book for cheap flights from Chicago to St. Louis: Tickets reserved on a Sunday cost between 6% and 13% less than those reserved on a Friday, according to ARC data. The data also suggests booking early can also lead to cheaper airfares. You could save 24% by buying your tickets for domestic flights at least a month in advance and 10% by booking international flights 2 months in advance.

 

How to find cheap round-trip tickets from Chicago to St. Louis

Being flexible with your dates and using Expedia's Price Drop Protection and Price Tracking features are some of the best ways of finding a cheap ticket from Chicago to St. Louis in 2025. You can also book with separate airlines for your outbound and return journeys, from $46 one-way. Expedia also offers Price Drop Protection, so if the cost of your airfare goes down after booking, you'll receive a credit for the difference*. This is available for a small fee, and is free to One Key Gold and Platinum tier members.

 

Expedia's Price Tracking feature means you can stay on top of airfares without manually checking every day. It sends you automated price alerts for cheap Chicago to St. Louis flights and uses historical data to indicate when the best time to book is. Download Expedia's free app to activate this handy tool in a few easy taps.

 

You could also save big by booking one of Expedia's vacation packages. Bundling together your Chicago to St. Louis airfare with your accommodations and car rental is often cheaper than booking everything separately. There’s also One Key, Expedia's generous rewards program. Join for free and you could earn One Key cash on most bookings to save on future adventures.

 

*Terms apply.

 

Disclaimer: ARC The statistics are based on average round-trip ticket prices between January and August 2023. The percentages you see are averages.

 

Frequently asked questions

How much does a flight from O'Hare Intl. Airport (ORD) to Lambert-St. Louis Intl. Airport (STL) cost?
You can land cheap return fares from O'Hare Intl. Airport (ORD) to Lambert-St. Louis Intl. Airport (STL) starting from $91. Snag a seat and get ready for takeoff. This information is based on the cheapest price found on Expedia for this return journey departing within the next three months. This airfare is for a United and Southwest Airlines flight leaving ORD on July 29 2025 and touching down at STL. The price was last updated on July 3 2025 and has not changed since.
What is the cheapest month to fly from ORD to STL?
The cheapest flights from ORD to STL are usually during off-peak season, when demand is lower. To save money, avoid flying during public holidays, school breaks and major local events.
Which airlines fly direct from O'Hare Intl. Airport (ORD) to Lambert-St. Louis Intl. Airport (STL)?
When flying out of O'Hare Intl. Airport (ORD), you can board a nonstop flight to Lambert-St. Louis Intl. Airport (STL) with United Airlines.
What is the cheapest airline that flies from ORD to STL?
With prices as low as $46 for a one-way flight from ORD to STL, United is currently the cheapest airline flying this route. This fare is based on the lowest price found on Expedia departing within the next three months. The flight takes off from ORD on September 23 2025. Prices were last updated on July 3 2025 and have not changed since.
How many flights per day from O'Hare Intl. Airport (ORD) to Lambert-St. Louis Intl. Airport (STL)?
When jetting out of O'Hare Intl. Airport (ORD), you can take your pick from an average of 11 daily nonstop flights to Lambert-St. Louis Intl. Airport (STL).
What are the most popular departure times for flights from O'Hare Intl. Airport (ORD) to Lambert-St. Louis Intl. Airport (STL)?
Flights between ORD and STL are busiest at 12 PM. If you'd like a quieter trip and potentially cheaper fares, look for a time outside the usual busy windows.
What day of the week has the most flights from ORD to STL?
Friday offers the most flights from O'Hare Intl. Airport (ORD) to Lambert-St. Louis Intl. Airport (STL). Consider taking off on this day and you'll have the best chance of finding a departure that works with your plans.
What is the earliest flight from O'Hare Intl. Airport (ORD) to Lambert-St. Louis Intl. Airport (STL)?
O'Hare Intl. Airport (ORD)'s earliest flight to Lambert-St. Louis Intl. Airport (STL) leaves at approximately 9:15AM UTC-6. With a flight time of 1h 39m, you'll touch down at around 10:54AM UTC-6.
How long does it take to fly from O'Hare Intl. Airport (ORD) to Lambert-St. Louis Intl. Airport (STL)?
Flights from ORD to STL have an average travel time of 1 hour and 30 minutes. The distance between the two is 260 mi.
What airline has the least delays from ORD to STL?
With 82% of flights generally arriving on schedule, Alaska Airlines has the best on-time performance for nonstop flights from O'Hare Intl. Airport (ORD) to Lambert-St. Louis Intl. Airport (STL). To keep track of your flight status and receive notifications about any changes, use the Expedia App.
What is the best time to fly from O'Hare Intl. Airport (ORD) to Lambert-St. Louis Intl. Airport (STL)?
Opt for a flight from O'Hare Intl. Airport (ORD) to Lambert-St. Louis Intl. Airport (STL) that leaves before 3 PM to reduce the risk of delays and cancellations. Later departures have a 22% higher chance of being canceled, on average.**Most reliable time of the day and month to travel recommendation is based on January through August 2024 flight status data sourced from OAG's global flight data platform.
What airports do you fly into for St. Louis from O'Hare Intl. Airport (ORD)?
If you're flying on a direct flight from O'Hare Intl. Airport (ORD) to St. Louis, Lambert-St. Louis Intl. Airport (STL) is the only airport you can touch down at.
Is it cheaper to buy a plane ticket from O'Hare Intl. Airport (ORD) to Lambert-St. Louis Intl. Airport (STL) last-minute?
Holding off until just before your trip to book a flight from ORD to STL often results in higher prices. While you might find some last-minute discounts, there's no guarantee. Be flexible with your travel plans to maximize your chances of getting a bargain.
Is it cheaper to book an ORD to STL flight and hotel package?
Compared with arranging flights and hotels separately, booking an ORD to STL flight and hotel package with Expedia could result in significant savings. Better still, having everything in one place takes the hassle out of travel planning. Just pick your flights and choose from our extensive range of stays, then customize your trip with extras like activities and car rentals.
Can I cancel or change the date of my flight from O'Hare Intl. Airport (ORD) to Lambert-St. Louis Intl. Airport (STL)?
It's generally possible to reschedule or cancel your ORD to STL flight. However, for bookings made more than 24 hours ago, additional charges may apply. Refer to your airline's policies in your itinerary to see what changes are allowed and whether any costs are involved. You'll also find further details on our Customer Service portal.

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