STL - ORD

$49 Find Cheap Flights from St. Louis to Chicago O'Hare Airport

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from St. Louis to O'Hare Intl departing on 5/12. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy, 0 bags

KAYAK searches hundreds of travel sites at once for deals on flights to Chicago O'Hare Intl Airport

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from St. Louis to Chicago, as well as popular online travel agencies
These are the airlines KAYAK users have selected most often from within our search results in flight searches from St. Louis to Chicago, as well as popular online travel agencies
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41 299 237 searches in the past 7 days on KAYAK

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Everything you should know

Cheapest round-trip
$172
Typical prices: $361-$247
Frontier
Sat 5/23Tue 5/26
STL - ORD • 1 stop
Cheapest non-stop
$187
Typical prices: $361-$244
United Airlines
Tue 5/5Wed 5/6
STL - ORD • Non-stop
Advice from real travelers
AI-powered summary based on content written by travel experts. AI can make mistakes.
American's Basic Economy is budget-friendly with carry-on.
Avoid peak hours at STL to reduce security wait times.
Expert advice
Expert advice
Expert advice
Expert advice
Top airlines
Cheapest • from $172 (round-trip)
Best reviews • 7.4 score
Airline reviews
Airline reviews
+1
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Airline reviews
Airline reviews
+1
Nonstop flights
You can fly direct with American Airlines and United Airlines. Average duration is 1h 30m
Direct flights
Direct flights
+1
+1
Direct flights
Direct flights
+1
Top layover airports
Cheapest • Avg $80 (round-trip)
Shortest trip • 3h 35m (one-way)
Insights
Insights
Insights
Insights
When to book
in advance
Our data shows that travelers who book at least 4 weeks in advance save around 65% compared to booking last minute.
Insights
Insights
Insights
Insights
When to travel
Cheapest • 32% price drop
Most popular
Good to know
Good to know
+1
+1
Good to know
Good to know
+1
Start a new search
KAYAK searches 100s of sites at once to find you the best travel deals.
We hope you love your trip to O'Hare Intl!
Flight Deals
Booking Insights
Expert advice
Flight Deals

Cheap Flights from St. Louis to O'Hare Intl (STL-ORD)

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from St. Louis to O'Hare Intl that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from St. Louis to O'Hare Intl

Sat, May 23 - Tue, May 26
Frontier Logo
8:16 pm - 4:06 pm
STL
-
ORD
19h 50m
1 stop
Frontier Logo
6:55 am - 8:55 am
ORD
-
STL
26h 00m
1 stop
$172Frontier
Tue, May 5 - Wed, May 27
Frontier Logo
6:51 pm - 8:32 pm
STL
-
ORD
25h 41m
2 stops
Frontier Logo
9:37 pm - 7:23 pm
ORD
-
STL
21h 46m
1 stop
$177Frontier
Mon, May 11 - Mon, May 18
Frontier Logo
5:27 pm - 7:55 am
STL
-
ORD
14h 28m
1 stop
Frontier Logo
4:05 pm - 8:55 am
ORD
-
STL
40h 50m
2 stops
$178Frontier
Sun, May 10 - Sun, May 17
Frontier Logo
4:19 pm - 11:13 pm
STL
-
ORD
6h 54m
1 stop
Frontier Logo
6:50 am - 4:54 pm
ORD
-
STL
10h 04m
1 stop
$181Frontier
Thu, Apr 30 - Mon, May 4
Frontier Logo
11:21 am - 11:59 pm
STL
-
ORD
12h 38m
2 stops
Frontier Logo
4:28 pm - 5:36 pm
ORD
-
STL
25h 08m
1 stop
$182Frontier
Thu, May 7 - Tue, May 12
Frontier Logo
6:55 pm - 11:59 pm
STL
-
ORD
29h 04m
2 stops
Frontier Logo
6:55 am - 5:33 pm
ORD
-
STL
10h 38m
1 stop
$183Frontier
Tue, May 12 - Sat, May 16
Delta Logo
5:15 pm - 10:27 pm
STL
-
ORD
5h 12m
1 stop
Delta Logo
7:05 am - 2:51 pm
ORD
-
STL
7h 46m
1 stop
$184Delta
Tue, May 5 - Wed, May 6
United Airlines Logo
9:21 am - 10:45 am
STL
-
ORD
1h 24mnonstop
United Airlines Logo
9:20 pm - 10:45 pm
ORD
-
STL
1h 25mnonstop
$187United Airlines
Sat, May 2 - Sun, May 17
Frontier Logo
8:23 pm - 11:33 am
STL
-
ORD
15h 10m
1 stop
Frontier Logo
6:50 am - 8:55 am
ORD
-
STL
26h 05m
1 stop
$188Frontier
Tue, May 12 - Sat, May 16
Delta Logo
6:21 am - 1:01 pm
STL
-
ORD
6h 40m
2 stops
Delta Logo
5:41 pm - 11:21 pm
ORD
-
STL
5h 40m
1 stop
$189Delta
Booking Insights

KAYAK's insights & trends for St. Louis to O'Hare Intl flights

Get data-powered insights and trends into flights from St. Louis to O'Hare Intl to help you find the cheapest flights, the best time to fly and much more.

How much is a round-trip flight from St. Louis to Chicago O'Hare Intl Airport?

This analysis is based on the cheapest round-trip price found on KAYAK in the last 12 months by searching for a flight from St. Louis to Chicago O'Hare Intl Airport departing in May.

What’s the cheapest day of the week to fly from St. Louis to Chicago O'Hare Airport?

The average price of all round-trip flights from St. Louis to Chicago O'Hare Intl Airport clicked on KAYAK for each day over the last 12 months.

When flying from St. Louis to Chicago O'Hare Airport, you should consider leaving on a Thursday and avoid Mondays if you are looking for the best rates. For your return to St. Louis, you’ll find the best rates on Saturdays and the most expensive ones on Mondays.

What is the cheapest month to fly from St. Louis to Chicago O'Hare Intl Airport?

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from St. Louis to Chicago O'Hare Intl Airport, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.

The cheapest month for flights from St. Louis to Chicago O'Hare Intl Airport is September, where tickets cost $211 (return) on average. On the other hand, the most expensive months are January and April, where the average cost of round-trip tickets is $399 and $391 respectively.

Can I save money by flying with a layover from St. Louis to Chicago O'Hare Intl Airport?

The average round-trip price for all non-stop flights, flights with one layover, and flights with two layovers for the route found by users searching on KAYAK in the last 2 weeks.

Yes, flying with a layover may cost you more time, but you can also save money on the route, with a 1 stop layover the cheapest option at $224 on average.

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

To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights from St. Louis to Chicago O'Hare Intl Airport, removes the top 0.1% to account for outliers, and then takes the average of all the values for each week.

To get a below average price on the flight from St. Louis to Chicago O'Hare Intl Airport, you should book around 4 weeks before departure, which saves you about 65% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 11 weeks before departure.

Expert advice

Expert advice for your flight from St. Louis to O'Hare Intl

 
AI-powered summary based on content written by travel experts. AI can make mistakes.
KAYAK teamed up with top travel experts to share the best tips for your journey.
Our travel experts
Stefanie Waldek

Stefanie Waldek

Expert on Qatar Airways, United Airlines and ORD

Stefanie Waldek is a freelance space, travel, and design writer based in Saratoga Springs, NY. Her words have appeared in Space.com, Travel + Leisure, Condé Nast Traveler, Architectural Digest, and House Beautiful, among other publications. An expert in aviation and expedition cruising, Stefanie is frequently up in the air or on the sea, likely en route to Antarctica or the Arctic.

Gabriel Leigh

Gabriel Leigh

Expert on ANA

Gabriel is a writer and video creator. As senior content producer for Flightradar24 and Monocle’s transport correspondent, he keeps a close eye on aviation in particular. He has also written travel articles for the likes of The New York Times. Born in New York but raised around the world, he now lives in Sweden. He’s been to 75 countries, flying 2.3 million miles on 113 airlines and through 234 airports in the process.

Jessica Macdonald

Jessica Macdonald

Expert on Lufthansa

Currently based in Scotland after living in South Africa and the United States, Jessica has been writing travel and aviation content for more than 10 years. She regularly contributes to Travel + Leisure and TripSavvy, and has had work published by Condé Nast Traveller and The Independent. She has traveled to more than 50 countries across six continents.

Duncan Madden

Duncan Madden

Expert on British Airways

Duncan is a freelance travel writer, copywriter and book author in constant search of travel stories and the perpetual sensation of being on holiday. He’s never happier than when on a dusty trail in search of empty waves or ducking under the piste tape in search of snowbound solitude. British born, living in Germany, but happiest heading for the horizon. His first book, Found in Translation, explores the etymologies and stories of country names around the world and is out now.

Harriet Baskas

Harriet Baskas

Expert on American Airlines

Harriet is an award-winning journalist who is happiest in an airport or an unusual museum. Her stories about airports, air travel, and the business of travel have appeared on NBC News, CNBC, USA TODAY, The Points Guy and other outlets. She is the creator of the StuckatTheAirport.com blog and the author of nine books. When not out on the road or exploring the latest airport amenities, she’s home in Seattle getting ready for the next adventure.

Yulia Denisyuk

Yulia Denisyuk

Expert on STL

Yulia is a freelance journalist who’s dispatched from 90+ countries. Her work focuses on cultures, adventure trips and air travel, appearing in NatGeo, NYT, CNTraveler, and more. For past assignments, she’s stayed with nomads in Mongolia and learned the art of Imigongo in Rwanda. She’s based in Chicago; in winter she often questions that decision.

Good to know

Low seasonDecember
Cheapest flight$49
Best time to beat the crowds with an average 19% drop in price.
Most popular time to fly with an average 4% increase in price.
Flight from St. Louis to Chicago O'Hare Airport

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

Are your dates flexible? Find out the best times to travel from St. Louis to O'Hare Intl based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price
KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or round-trips with a duration up to 40 days. While we try to provide actual minimum prices for each date, some prices are predictions and actual prices may differ.

FAQs for booking St. Louis to Chicago O'Hare Airport flights

  • What is the cheapest flight from St. Louis to Chicago O'Hare Intl Airport?

    In the last 3 days, the lowest price for a flight from St. Louis to Chicago O'Hare Intl Airport was $49 for a one-way ticket and $172 for a round-trip.

  • Do I need a passport to fly between St. Louis and Chicago O'Hare Airport?

    No

  • Which airports will I be using when flying from St. Louis to Chicago O'Hare Airport?

    St. Louis and Chicago O'Hare Airport are both served by 1 main airport. You will leave St. Louis from Lambert-St Louis and will be arriving at Chicago O'Hare Intl.

  • Which airlines offer Wi-Fi service onboard planes from St. Louis to Chicago O'Hare Airport?

    All the following airlines offer inflight Wi-Fi service on the St. Louis to Chicago O'Hare Airport flight route: American Airlines, Air Canada, Delta, Lufthansa, Alaska Airlines, and United Airlines.

  • Which aircraft models fly most regularly from St. Louis to Chicago O'Hare Airport?

    The Boeing 737 MAX 8 is the aircraft model that flies most regularly on the St. Louis to Chicago O'Hare Airport flight route.

  • Which airline alliances offer flights from St. Louis to Chicago O'Hare Airport?

    Star Alliance, and oneworld are the airline alliances operating flights between St. Louis and Chicago O'Hare Airport, with Star Alliance being the most commonly used for this route.

  • On which days can I fly direct from St. Louis to Chicago O'Hare Airport?

    There are nonstop flights from St. Louis to Chicago O'Hare Airport on a daily basis.

  • Which is the best airline for flights from St. Louis to Chicago, United Airlines or American Airlines?

    The two airlines most popular with KAYAK users for flights from St. Louis to Chicago are United Airlines and American Airlines. With an average price for the route of $353 and an overall rating of 7.4, United Airlines is the most popular choice. American Airlines is also a great choice for the route, with an average price of $296 and an overall rating of 7.1.

  • How does KAYAK find such low prices on flights from St. Louis to Chicago O'Hare Airport?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from St. Louis to Chicago O'Hare Airport.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from St. Louis to Chicago O'Hare Airport?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Chicago O'Hare Airport from St. Louis is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from St. Louis to Chicago O'Hare Airport?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to Chicago O'Hare Airport with an airline and back to St. Louis with another airline. Booking your flights between St. Louis and ORD can sometimes prove cheaper using this method.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from St. Louis to Chicago O'Hare Airport?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to Chicago O'Hare Airport from St. Louis up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

KAYAK’s top tips for finding a cheap flight from St. Louis to Chicago O'Hare Intl Airport

  • Looking for a cheap flight? 25% of our users found flights on this route for $230 or less one-way and $441 or less round-trip.

Prefer to fly direct from St. Louis to Chicago O'Hare Airport?

 
Direct data is based off flight results for the next 60 days. Find direct flights from all airlines flying direct from Lambert-St Louis to Chicago O'Hare Intl.
Find which airlines fly direct from Lambert-St Louis Airport to Chicago O'Hare Intl Airport, which days they fly and book direct flights.

Direct departures

Lambert-St Louis to Chicago O'Hare Intl

Monday

American Airlines,United Airlines

American Airlines,United Airlines

Tuesday

American Airlines,United Airlines

American Airlines,United Airlines

Wednesday

American Airlines,United Airlines

American Airlines,United Airlines

Thursday

American Airlines,United Airlines

American Airlines,United Airlines

Friday

American Airlines,United Airlines

American Airlines,United Airlines

Saturday

American Airlines,United Airlines

American Airlines,United Airlines

Sunday

American Airlines,United Airlines

American Airlines,United Airlines

See more direct flights

Direct returns

Chicago O'Hare Intl to Lambert-St Louis

Monday

American Airlines,United Airlines

American Airlines,United Airlines

Tuesday

American Airlines,United Airlines

American Airlines,United Airlines

Wednesday

American Airlines,United Airlines

American Airlines,United Airlines

Thursday

American Airlines,United Airlines

American Airlines,United Airlines

Friday

American Airlines,United Airlines

American Airlines,United Airlines

Saturday

American Airlines,United Airlines

American Airlines,United Airlines

Sunday

American Airlines,United Airlines

American Airlines,United Airlines

See more direct flights

Reviews of the top 3 airlines serving from St. Louis to O'Hare Intl

 
See real verified KAYAK customer reviews for airlines flying from St. Louis to Chicago. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from St. Louis to O'Hare Intl? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
7.4
United AirlinesOverall score based on 9587 reviews
7.1Entertainment
7.7Boarding
6.6Food
7.3Comfort
8.1Crew
Airline reviews

Very comfortable flight, snacks and drinks were good, good communication from crew. Could have used a little more information on timing of boarding for group 5

10.0 ExcellentJim, Apr 2026
BWI - ORD
Read more United Airlines reviews

Very comfortable flight, snacks and drinks were good, good communication from crew. Could have used a little more information on timing of boarding for group 5

Great flight. Got to watch a movie. Smooth flight and early arrival at ORD.

It was better than excellent. The staff in Mason City were great. The young woman that pushed my wheelchair did more than could be expected of her. She came from India 17 years ago. I don't remember her name.

After arriving in Chicago, we were taxiing for 1.5 hours with infrequent and untruthful updates about the amount of time it would take to arrive at the gate. Minimally, the team could have provided timing expectations that were more truthful, especially one their original expectations were not met.

Every staff member was professional, friendly and courteous. The pizza twist was ok. It was warm but too much dough.

I had a terrible experience. My flight got delayed from Atlanta to Chicago on Monday April 6, 2026, and that led to me missing my next flight to Brussels. United Airlines didn’t provide me with any accommodation for shelter. I had to sleep at the airport in Chicago. The next flight I was put on didn’t leave until the evening hours of Tuesday 4/7/2026.

The flight was officially delayed 3 times, and was actually later than that. Combined, it was a 3 hour delay, but there was no recognition (miles, voucher, etc). The crew seemed stressed. The captain sounded nervous in his announcements. The flight itself was smooth and uneventful.

Just a bad day to fly. Flight was delayed from scheduled 6:50 pm departure to 8:50 pm. Combination of factors mostly related to weather at the destination airport (which is where the incoming flight originated) which delayed the inbound flight over an hour. Once on board, we taxied but had to hold again on the taxiway for 10 minutes or so. We did not get wheels up until after 9 pm. The flight was smooth but about 18 minutes from our destination, we had to hold for several minutes more due to weather at ORD. We finally landed at ORD about 11:08 pm (accounting for the time difference, that was about a 3 hour delay from our scheduled departure time). It felt like we were never going to get to our destination. But the flight crew and attendants were very good. The movie selection onboard was also very nice. Got to watch half of a movie just during our taxi from the gate at ATL due to the delay!

3 hour delay…. Nearly 2 hours sitting on tarmac. Do better, United. Or at least have the sense to not say “we hope you enjoyed your flight with us” upon disembarking.

Flights were on time. Free Wifi on plane. Everything was well organized.

The staff and service on American Airlines were truly outstanding. I had requested wheelchair assistance for my mother due to her knee issues, and the team went above and beyond every step of the way—from boarding in Boston to our arrival in Chicago. Their care, professionalism, and attentiveness made the entire experience smooth and stress-free. I’m very grateful for the support they provided.

The new planes (American Eagle) are beautiful and especially comfortable. The flight attendants are consistently professional and courteous. And, while it may seem inconsequential, the new liquid tube of coffee creamer—in contrast to the powdered coffee creamer—makes all the difference in a cup of coffee.

I'm not sure American is capable of on-time arrivals and departures. When you land at ORD, you almost always get held on the tarmac because your gate is still occupied. I may have missed my connection, but that ended up up being significantly delayed as well. Once again, I finally got home well after midnight.

Crew at the gate was very crabby and not at all polite. The plane was very hot the entire flight. And the seat cushion was very worn out.

The staff are very, very professional. It's what flying should feel like.

Flight was delayed half hour before boarding, but when I checked flight aware the plane that would Pick us up had a delay of more than an hour. AA should let us know in advance to avoid waiting several hours in the airport

Delays with no explanation. It could have been handled better.

Jill was the flight attendant in first class she was fabulous!! Best flight attendant I have had in years.!! And I fly every other week. Other can learn from her!!

As a first class customer, there was no power the entire flight which limited my ability to work. I find this unacceptable. The first 11 rows on the left side of the plan were out. I was only offered the option to charge my phone which was not the issue because my laptop was out of power. I asked if there was anything that can be done for me, and the answer was, "no". I was not offered any type of compensation for this AA problem which caused me unnecessary stress due to inability to address business issues on an already challenging travel day. Flight attendants tried to reset the power once but that was the extent of their support. Very disappointing for the lack of expected services on a flight. Please contact me with customer focused response to this complaint.

There was no inflight service. Once we landed we were delayed to find a gate for an hour and a half which was 1/2 the total time in the air.

Both were great flights with wonderful pilots! It was not fancy, very simple. But boarding was super easy and the flight was smooth. Pick up in DFW was at corporate terminal which was the only confusing part for uber but if you call the uber driver and drop a pin they come right to it.

Totally great experience. Would definitely travel with them again. Thanks.

Both my fights got cancelled. Said mechanical issues but on flight tracker the flights came in and left! We were lied to!!

Was very impressed they called to confirm he would be on the flight. Great customer service!

We had a wonderful flight due to the care of our experienced pilot and copilot and the magnificent air views from our comfortable seats. What excitement to be in such a small plane with such magnificent around us.

Multiple time changes, then we left earlier than we were told.

Communication could be better but the staff and crew were over the top friendly and helpful, The flight itself was smooth.

flight was cancelled literally at 10pm the night before an early morning flight with hardly any time to reschedule. Will never book with kayak again.

My flight was cancelled 12 hours before takeoff. I was not able to reschedule another flight to make connections and had to cancel the entire trip. The ticket that was supposed to replace the cancelled flight had no boarding pass and I was unable to get one at the airport so I was denied access to the rescheduled flight. I was refunded but I missed my daughter's birthday.

I had a family emergency and couldn’t make the flight, and they wouldn’t let me cancel/refund it (a *month* ahead of time), were especially difficult with me on the phone, and wouldn’t let me even so much as reschedule the flight or get credit.

Everything you need to know for your flight from St. Louis to O'Hare Intl

Information on your arrival and departure airports