STL - ORD

$43 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 3/21. 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
Travelers love KAYAK
41 299 237 searches in the past 7 days on KAYAK

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Everything you should know

Cheapest round-trip
$195
Typical prices: $218-$359
Frontier
Fri 3/6Wed 3/11
STL - ORD • 1 stop
Cheapest non-stop
$208
Typical prices: $222-$361
United Airlines
Thu 3/12Fri 3/13
STL - ORD • Non-stop
Our travelers' advice
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
Frontier
Cheapest • from $195 (round-trip)
United Airlines
Best reviews • 7.4 score
Airline reviews
Airline reviews
+1
+1
Airline reviews
Airline reviews
+1
When to book
4 weeks
in advance
Our data shows that travelers who book at least 4 weeks in advance save around 63% compared to booking last minute.
Insights
Insights
Insights
Insights
When to travel
September
Cheapest • 27% price drop
March
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

Fri, Mar 6 - Wed, Mar 11
Frontier Logo
1:09 pm - 10:39 pm
STL
-
ORD
9h 30m
1 stop
Frontier Logo
4:18 pm - 11:19 pm
ORD
-
STL
7h 01m
1 stop
$195Frontier
Sat, May 2 - Sat, May 2
Delta Logo
6:48 am - 12:49 pm
STL
-
ORD
6h 01m
1 stop
Delta Logo
5:04 pm - 11:13 pm
ORD
-
STL
6h 09m
2 stops
$196Delta
Sat, Jun 13 - Sun, Jun 14
United Airlines Logo
6:00 am - 7:30 am
STL
-
ORD
1h 30mnonstop
United Airlines Logo
7:45 pm - 9:16 pm
ORD
-
STL
1h 31mnonstop
$201United Airlines
Sat, May 2 - Sat, May 2
Delta Logo
6:20 am - 12:49 pm
STL
-
ORD
6h 29m
2 stops
Delta Logo
5:04 pm - 11:13 pm
ORD
-
STL
6h 09m
2 stops
$202Delta
Sat, May 16 - Sun, May 17
American Airlines Logo
5:51 am - 7:21 am
STL
-
ORD
1h 30mnonstop
American Airlines Logo
7:15 am - 1:22 pm
ORD
-
STL
6h 07m
1 stop
$204American Airlines
Mon, Mar 2 - Fri, Mar 6
Frontier Logo
3:49 pm - 11:15 pm
STL
-
ORD
7h 26m
1 stop
Frontier Logo
8:55 pm - 11:19 am
ORD
-
STL
14h 24m
1 stop
$205Frontier
Sun, Jun 28 - Mon, Jul 20
American Airlines Logo
6:00 am - 7:29 am
STL
-
ORD
1h 29mnonstop
American Airlines Logo
10:26 pm - 11:42 pm
ORD
-
STL
1h 16mnonstop
$207American Airlines
Thu, Mar 12 - Fri, Mar 13
United Airlines Logo
7:41 am - 9:10 am
STL
-
ORD
1h 29mnonstop
United Airlines Logo
1:12 pm - 2:43 pm
ORD
-
STL
1h 31mnonstop
$208United Airlines
Thu, Mar 5 - Sun, Mar 8
American Airlines Logo
6:00 am - 7:28 am
STL
-
ORD
1h 28mnonstop
American Airlines Logo
10:30 pm - 11:44 pm
ORD
-
STL
1h 14mnonstop
$209American Airlines
Fri, Apr 17 - Wed, Apr 22
Multiple Airlines Logo
8:13 pm - 2:20 pm
STL
-
ORD
18h 07m
1 stop
Multiple Airlines Logo
7:20 pm - 7:12 pm
ORD
-
STL
23h 52m
2 stops
$210Multiple Airlines
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 March.

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 Friday and avoid Wednesdays if you are looking for the best rates. For your return to St. Louis, you’ll find the best rates on Wednesdays and the most expensive ones on Tuesdays.

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 July, where the average cost of round-trip tickets is $399 and $349 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 63% 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$43
Best time to beat the crowds with an average 15% drop in price.
Most popular time to fly and prices are also 3% lower on average.
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 $43 for a one-way ticket and $195 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, Delta, Air Canada, Alaska Airlines, United Airlines, and Lufthansa.

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

    The Canadair (Bombardier) Regional Jet CRJ-550 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 $330 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 $293 and an overall rating of 7.2.

  • 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 $229 or less one-way and $470 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, Aer Lingus

American Airlines, United Airlines, +1 more

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 9307 reviews
7.7Boarding
7.3Comfort
6.6Food
7.1Entertainment
8.1Crew
Airline reviews

Crew was great (professional, attentive, prompt). Snacks for 4 hrs flight is deplorable.

8.0 ExcellentDarly, Feb 2026
LAX - ORD
Read more United Airlines reviews

Crew was great (professional, attentive, prompt). Snacks for 4 hrs flight is deplorable.

United Airlines is my preferred airlines and I am thankful for Gary who also help support me on the phone to switch my flight literally last min.

Seated dude next to me even though lots of empty rows. But main thing was we sat on the tarmac after landing for 30 minutes because of, in the words of the dude who sat next to me, “operational incompetence”. We got changing directions about where to pick up gate checked bags. Pilot and flight attendant were awesome though.

It was a pretty standard flight... until the almost hour and a half spent on the taxi way. I get that the weather has been poor but the delay had nothing to do with the weather and more to do with a plane with several issues tying up the gate. I get that that happens from time to time but this has been EVERY flight I've been on for the past 5 years and I fly 3 to 5 times a year. This isn't just United... it's American, it's Delta. It's an issue with the entire industry. I work for UPS and packages on a cargo plane get better service than people do these days. Anymore I HATE flying.

Perfect flight. Smooth flight. Arrived 20 minutes early at destination. Excellent service.

The flights were on time which was great give. It was holiday travel season and there’d been some weather issues. The only complaint and this is every time with United is the terrible seat design. The head rest is not built for comfort and having my neck bent forward for a cross country trip reminded me while I try not to take United flights as a rule.

Everything was absolutely wonderful from check in to baggage claim. Staff was very professional and sweet. Will definitely recommend United to family and friends.

They did the one thing that really matters - got to Chicago early.

The flight was on time. I generally don’t drink or eat on short flights and the seats were good and the flight attendants were friendly. That’s all I expect

It was nice to have gotten up upgraded to first class with a meal on a three hour flight

Waited for oxygen tanks for 30 minutes after boarding was complete.

We flew in first class. The crew did not offer drinks before the flight took off, but they treated us well during the flight. The food was excellent. There was actually too much food served, but it was nice to have all the options.

Update to handle the delay was very bad, crews no smiles or welcome or thanks. Don’t care attitude

Pilot navigated severe weather/snow storm with skill. Described his intentions clearly

Little warm on the plane and delayed for an hour

So excited very proud first of all I wanna thank kayak all updates very professional and fast alart And amazing cabin crew so nice to me they deserve big salute

The boarding process needs to be fixed. The zone don't work, especially when there is hardly anyone in zones 3, 4,and 5, leaving the majority of the passengers backed up in the aisle, especially because passengers seated near the front are blocking passengers who are seated in the rear of the plane. It would also help if the size of carry on bags was more strictly enforced.

Awful. They won’t help me with anything. I booked on American but they abdicated to Iberia. The ticket was overpriced. Everything negative

I enjoyed the extra leg room compared to other airlines. The first stewards made my daughter’s birthday special by giving her an extra snack. Then the last one coming home from Chicago to Appleton made our night really enjoyable Thanks for making our trip enjoyable

It was good..clean, comfy seat. Friendly warm welcoming crew. Was able to check my cabin luggage at the gate which I was able to pickup in a decent time from baggage claim. The app gave all updates from delays to baggage claim info. Overall smooth flight.

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