What are the cheapest airlines flying from St. Louis to Chicago O'Hare Intl Airport round-trip?

Flying on American Airlines is currently your cheapest option to Chicago O'Hare Intl Airport, with prices starting at $91. Additional round-trip tickets that might be worth considering are offered by Southwest and Frontier, with the lowest prices starting at $111 and $112, respectively. American Airlines is 66% cheaper than the average price of flights available within the next 90 days to this destination.

What are the cheapest airlines to fly from St. Louis to Chicago O'Hare Intl Airport one-way?

For one-way options, check prices for American Airlines. According to our data, you can fly for as low as $49. Users have also found prices from $56 and $69 on Southwest and Frontier, respectively.

In terms of precipitation, rainfall in Chicago O'Hare Intl Airport ranges from 1.7 - 4.9 inches per month. August is typically the wettest month, when rainfall can reach 4.9 in. January is typically the driest time to visit Chicago O'Hare Intl Airport when rainfall is around 1.7 in.

If weather is an important factor for your trip to Chicago O'Hare Intl Airport, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 73.4 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 23.0 F).

What are the cheapest flights from St. Louis to Chicago O'Hare Intl Airport?

The cheapest flight price from St. Louis to Chicago O'Hare Intl Airport is $134. On average you can expect to pay $2,041. The most popular route, (Lambert-St Louis - Chicago O'Hare Intl), can usually be booked for $91.

What are the most reliable airlines from St. Louis to Chicago O'Hare Intl Airport?

Before booking your flight to Chicago O'Hare Intl Airport from St. Louis, check out the most reliable airlines to get you to your destination on time: Republic Airways (94%), Qatar Airways (85%), Aer Lingus( 85%).

What are the most popular airlines that fly from St. Louis to Chicago O'Hare Intl Airport?

Consider Southern / Mokulele, American Airlines or United Airlines when booking your flight. These represent the most popular airlines when flying from St. Louis to Chicago O'Hare Intl Airport.

What is the cheapest day to fly round-trip from St. Louis to Chicago O'Hare Intl Airport?

Wednesday is generally a great day to depart. Flying on this day could help you save up to 20%.

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

Users have found that booking a flight from St. Louis to Chicago O'Hare Intl Airport at least 52 days early can save you up to 220% on average compared to booking a flight this week. If booking 52 days before your flight isn’t an option for you, users have found flights from St. Louis to Chicago O'Hare Intl Airport for as little as $125 when booking for a departure date within the next two weeks. You can also check prices now. Some users have found airline tickets as low as $274 for flights departing within the next 3 days.

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

August can be a great time to fly to Chicago O'Hare Intl Airport from St. Louis with a flight ticket averaging about $247. Cheapflights users have found deals in the month of August for as cheap as $108. The most expensive prices can be found in the month of June.

What airport do you fly from for flights from St. Louis to Chicago O'Hare Intl?

If you book a flight to Chicago O'Hare Intl from St. Louis, you will be flying from 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 43 flights from Lambert-St Louis to Chicago O'Hare Intl per day from 3 different airlines.

Can I find deals for flights from St. Louis to O'Hare Intl that include hotel bookings?

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

How can I find direct flights from St. Louis to O'Hare Intl?

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

Can I find deals for business class flights from St. Louis to O'Hare Intl?

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

$49+ Flights from St. Louis to Chicago O'Hare Intl Airport

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Cheapflights Tip: The best prices from Lambert-St Louis to Chicago O'Hare Intl are usually found in August or September, booked 62 days in advance, depart on a Thursday or Friday and return on a Friday

Cheap flight deals from St. Louis to O'Hare Intl

Round-trip from	$91 (American Airlines)
One-way from	$49 (American Airlines)
Popular in	June
Cheapest in	August
Average price	$297
Good round-trip deal	$490 or less
Good one-way deal	$221 or less

From Lambert-St Louis to Chicago O'Hare Intl

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One-way flight from Lambert-St Louis to Chicago O'Hare Intl

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Highest demand for flights based on searches. 11% potential increase in price ($35 potential increase over avg. RT price).

Search Deals

Cheapest flight prices on average. 1% potential price decrease ($5 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 Lambert-St Louis to Chicago O'Hare Intl.

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Price to beat on a one-way flight from Lambert-St Louis to Chicago O'Hare Intl.

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Find flight deals from St. Louis to O'Hare Intl

Cheapest flights from St. Louis to O'Hare Intl
Explore the most affordable flight options available from St. Louis to O'Hare Intl. Find the lowest fares from popular airlines and budget airlines, with prices last updated on July 3, 2025.

Sat 8/97:44 pmSTL - ORD

Nonstop1h 31mAmerican Airlines

Tue 8/127:00 pmORD - STL

Nonstop1h 25mAmerican Airlines

Deal found 7/3

$91

Tue 8/122:25 pmSTL - ORD

1 stop7h 05mSouthwest

Tue 8/267:30 amORD - STL

1 stop7h 00mSouthwest

Deal found 7/1

$111

Thu 9/114:00 pmSTL - ORD

1 stop8h 10mFrontier

Sun 9/145:10 amORD - STL

1 stop9h 54mFrontier

Deal found 7/3

$112

Thu 7/318:00 amSTL - ORD

Nonstop1h 25mUnited Airlines

Thu 8/79:20 pmORD - STL

Nonstop1h 25mUnited Airlines

Deal found 7/1

$124

Sat 8/21:00 pmSTL - ORD

1 stop18h 37mSouthern / Mokulele

Mon 8/48:15 amORD - STL

1 stop3h 55mSouthern / Mokulele

Deal found 6/30

$165

Sat 8/910:30 amSTL - ORD

1 stop6h 03mDelta

Tue 8/127:05 amORD - STL

1 stop7h 36mDelta

Deal found 7/3

$177

Sat 7/262:52 pmSTL - ORD

1 stop8h 37mMultiple Airlines

Tue 7/291:10 pmORD - STL

1 stop3h 35mMultiple Airlines

Deal found 7/2

$180

Best flights from St. Louis to O'Hare Intl
Discover carefully curated flight deals from St. Louis to O'Hare Intl that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated July 3, 2025.

Wed 7/306:00 amSTL - ORD

Nonstop1h 24mAmerican Airlines

Wed 8/65:05 pmORD - STL

Nonstop1h 18mAmerican Airlines

Deal found 6/30

$91

Tue 8/122:25 pmSTL - ORD

1 stop7h 05mSouthwest

Tue 8/267:30 amORD - STL

1 stop7h 00mSouthwest

Deal found 7/1

$111

Thu 9/114:00 pmSTL - ORD

1 stop8h 10mFrontier

Sun 9/145:10 amORD - STL

1 stop9h 54mFrontier

Deal found 7/2

$112

Thu 7/318:00 amSTL - ORD

Nonstop1h 25mUnited Airlines

Thu 8/79:20 pmORD - STL

Nonstop1h 25mUnited Airlines

Deal found 7/1

$124

Sat 8/21:00 pmSTL - ORD

1 stop18h 37mSouthern / Mokulele

Mon 8/48:15 amORD - STL

1 stop3h 55mSouthern / Mokulele

Deal found 6/30

$165

Sat 8/96:40 amSTL - ORD

1 stop3h 36mDelta

Tue 8/125:45 amORD - STL

1 stop4h 12mDelta

Deal found 7/2

$177

Sat 7/262:52 pmSTL - ORD

1 stop8h 37mMultiple Airlines

Tue 7/291:10 pmORD - STL

1 stop3h 35mMultiple Airlines

Deal found 7/2

$180

Last-minute flights from St. Louis to O'Hare Intl
Discover last-minute flight deals from St. Louis to O'Hare Intl. Data last updated July 3, 2025 and is based on user searches.

Wed 7/911:24 amSTL - ORD

1 stop9h 04mSpirit Airlines

Wed 7/166:02 pmORD - STL

2 stops15h 50mSpirit Airlines

Deal found 7/2

$329

Thu 7/102:36 pmSTL - ORD

1 stop9h 46mFrontier

Sun 7/135:01 amORD - STL

1 stop8h 33mFrontier

Deal found 7/2

$145

Thu 7/109:20 amSTL - ORD

1 stop7h 12mSouthern / Mokulele

Tue 7/158:15 amORD - STL

1 stop3h 55mSouthern / Mokulele

Deal found 7/1

$217

Thu 7/109:50 amSTL - ORD

3 stops14h 03mMultiple Airlines

Tue 7/155:05 amORD - STL

1 stop11h 26mMultiple Airlines

Deal found 7/1

$322

Sat 7/127:55 amSTL - ORD

Nonstop1h 25mUnited Airlines

Mon 7/289:20 pmORD - STL

Nonstop1h 25mUnited Airlines

Deal found 7/2

$470

Sat 7/128:01 pmSTL - ORD

Nonstop1h 29mAmerican Airlines

Mon 7/285:15 amORD - STL

1 stop6h 43mAmerican Airlines

Deal found 7/2

$480

Sat 7/262:52 pmSTL - ORD

1 stop8h 37mMultiple Airlines

Tue 7/291:10 pmORD - STL

1 stop3h 35mMultiple Airlines

Deal found 7/2

$180

Wed 7/306:00 amSTL - ORD

Nonstop1h 24mAmerican Airlines

Wed 8/65:05 pmORD - STL

Nonstop1h 18mAmerican Airlines

Deal found 6/30

$91

Thu 7/318:00 amSTL - ORD

Nonstop1h 25mUnited Airlines

Thu 8/79:20 pmORD - STL

Nonstop1h 25mUnited Airlines

Deal found 7/1

$124

Sat 8/21:00 pmSTL - ORD

1 stop18h 37mSouthern / Mokulele

Mon 8/48:15 amORD - STL

1 stop3h 55mSouthern / Mokulele

Deal found 6/30

$165

Sat 8/96:40 amSTL - ORD

1 stop3h 36mDelta

Tue 8/125:45 amORD - STL

1 stop4h 12mDelta

Deal found 7/2

$177

Tue 8/122:25 pmSTL - ORD

1 stop7h 05mSouthwest

Tue 8/267:30 amORD - STL

1 stop7h 00mSouthwest

Deal found 7/1

$111

One-way flights from St. Louis to O'Hare Intl
Search for one-way flight options from St. Louis to O'Hare Intl. Find affordable one-way fares based on user searches. Data last updated July 3, 2025.

Mon 9/17:23 amSTL - ORD

Nonstop1h 25mAmerican Airlines

Deal found 7/3

$49

Sat 8/96:35 amSTL - ORD

1 stop6h 10mSouthwest

Deal found 7/3

$56

Sun 9/214:00 pmSTL - ORD

1 stop8h 10mFrontier

Deal found 7/1

$69

Mon 9/83:20 pmSTL - ORD

Nonstop1h 25mUnited Airlines

Deal found 7/1

$79

Thu 7/241:00 pmSTL - ORD

1 stop3h 32mSouthern / Mokulele

Deal found 7/3

$83

Wed 9/106:40 amSTL - ORD

1 stop6h 05mDelta

Deal found 7/3

$89

Mon 8/410:47 amSTL - ORD

2 stops20h 17mSpirit Airlines

Deal found 6/30

$110

Fri 7/259:50 amSTL - ORD

2 stops11h 40mMultiple Airlines

Deal found 7/1

$122

Cheapflights Fare Finder

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

Sat 8/9

7:44 pm-9:15 pm

Nonstop1h 31m

Chicago O'Hare Intl

Tue 8/12

7:00 pm-8:25 pm

Nonstop1h 25m

$91

St. LouisChicago

STL - ORD

STLORD

Lambert-St Louis

Tue 8/12

2:25 pm-9:30 pm

1 stop7h 05m

Chicago O'Hare Intl

Tue 8/26

7:30 am-2:30 pm

1 stop7h 00m

$111

St. LouisChicago

STL - ORD

STLORD

Lambert-St Louis

Thu 9/11

4:00 pm-12:10 am

1 stop8h 10m

Chicago O'Hare Intl

Sun 9/14

5:10 am-3:04 pm

1 stop9h 54m

$112

St. LouisChicago

STL - ORD

STLORD

Lambert-St Louis

Thu 7/31

8:00 am-9:25 am

Nonstop1h 25m

Chicago O'Hare Intl

Thu 8/7

9:20 pm-10:45 pm

Nonstop1h 25m

$124

St. LouisChicago

STL - ORD

STLORD

Lambert-St Louis

Sat 8/2

1:00 pm-7:37 am

1 stop18h 37m

Chicago O'Hare Intl

Mon 8/4

8:15 am-12:10 pm

1 stop3h 55m

$165

St. LouisChicago

STL - ORD

STLORD

Lambert-St Louis

Sat 8/9

10:30 am-4:33 pm

1 stop6h 03m

Chicago O'Hare Intl

Tue 8/12

7:05 am-2:41 pm

1 stop7h 36m

$177

St. LouisChicago

STL - ORD

STLORD

Lambert-St Louis

Sat 7/26

2:52 pm-11:29 pm

1 stop8h 37m

Chicago O'Hare Intl

Tue 7/29

1:10 pm-4:45 pm

1 stop3h 35m

$180

St. LouisChicago

STL - ORD

STLORD

Lambert-St Louis

Mon 8/18

8:00 am-9:25 am

Nonstop1h 25m

$49

St. LouisChicago

STL - ORD

STLORD

Lambert-St Louis

Sat 8/9

6:35 am-12:45 pm

1 stop6h 10m

$56

St. LouisChicago

STL - ORD

STLORD

Lambert-St Louis

Sun 9/21

4:00 pm-12:10 am

1 stop8h 10m

$69

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/2

Showing 1-10 of 15 results

The best insider tips for St. Louis to Chicago O'Hare Intl Airport flights

Cheapflights partnered with top experts to bring you the best recommendations for your St. Louis to Chicago O'Hare Intl Airport trip

Airlines

Lufthansa

Lufthansa's Economy Flex offers preferred seating and same-day flight changes.

Lufthansa's Free Neighbor Seat allows extra space for a fee on long-haul flights.

Read more about Lufthansaby Blane Bachelor

United Airlines

Basic Economy on United allows no carry-on bags, only a personal item.

Prepay checked bag fees 24 hours before to save money on United flights.

Read more about United Airlinesby Harriet Baskas

Airports

STL

Security lines at STL are straightforward, averaging 5-10 minutes off-peak. Check real-time wait times online before heading to the airport.

ORD

For a quick city trip from ORD, take the 'L' train. It's often faster than taxis due to Chicago traffic.

Our travel experts

Blane Bachelor

Expert on Lufthansa

Harriet Baskas

Expert on United Airlines

Ramsey Qubein

Expert on ORD

Taryn White

Expert on STL

Best time to book a flight from St. Louis to O'Hare Intl

Have a flexible travel schedule? Discover the best time to fly to O'Hare Intl from St. Louis 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 St. Louis to Chicago O'Hare Intl Airport

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

To ensure you get the cheapest price possible for a flight from St. Louis to Chicago O'Hare Intl Airport, you should look to book at least 62 days in advance of your intended travel date. The price of your flight may increase if you delay and leave booking until a week or so before departure.

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

Currently, August is the cheapest month in which you can book a flight from St. Louis to Chicago O'Hare Intl Airport (average of $245). Flying from St. Louis to Chicago O'Hare Intl Airport in March is currently the most expensive (average of $321). 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 STL to ORD?

It’s typically best to fly out from St. Louis to Chicago O'Hare Intl Airport in the morning. Doing so could potentially save you 48% on the flight price compared to flying at noon, which is usually more expensive.

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

Travelers seeking maximum savings on their St. Louis to Chicago O'Hare Intl Airport flight should consider departing on Thursday mornings when fares are most often at their lowest. Saturday at noon flights should be avoided if possible as fares are typically the most expensive at this time.

Weekly flight availability from St. Louis to Chicago O'Hare Intl Airport

The most flights from STL to ORD are scheduled on a Wednesday (63 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (11 on average).

Reviews of airlines servicing O'Hare Intl

See what other customers who have flown with Southwest, Delta, and United Airlines from St. Louis to Chicago O'Hare Intl Airport 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

4,266 reviews

Reviews

1 / 20

8.0

Excellent

John,May 2025

PVD - BNA

It’s southwest so no frills but clean, efficient and got me to my location.

Southwest

8.0

Very good

4,266 reviews

Southwest

8.0

Very good

4,266 reviews

Reviews

1 / 20

8.0

Excellent

John,May 2025

PVD - BNA

It’s southwest so no frills but clean, efficient and got me to my location.

Delta

8.0

Very good

7,982 reviews

Southwest

8.0

Very good

4,266 reviews

Reviews

1 / 20

8.0

Excellent

John,May 2025

PVD - BNA

It’s southwest so no frills but clean, efficient and got me to my location.

United Airlines

7.4

Good

8,861 reviews

Southwest

8.0

Very good

4,266 reviews

Reviews

1 / 20

8.0

Excellent

John,May 2025

PVD - BNA

It’s southwest so no frills but clean, efficient and got me to my location.

American Airlines

7.2

Good

10,000 reviews

Southwest

8.0

Very good

4,266 reviews

Reviews

1 / 20

8.0

Excellent

John,May 2025

PVD - BNA

It’s southwest so no frills but clean, efficient and got me to my location.

Related info for your journey

What airport do you fly from for flights from St. Louis to Chicago O'Hare Intl?
If you book a flight to Chicago O'Hare Intl from St. Louis, you will be flying from 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 43 flights from Lambert-St Louis to Chicago O'Hare Intl per day from 3 different airlines.
What are the cheapest airlines flying from St. Louis to Chicago O'Hare Intl Airport round-trip?
Flying on American Airlines is currently your cheapest option to Chicago O'Hare Intl Airport, with prices starting at $91. Additional round-trip tickets that might be worth considering are offered by Southwest and Frontier, with the lowest prices starting at $111 and $112, respectively. American Airlines is 66% cheaper than the average price of flights available within the next 90 days to this destination.
What are the cheapest airlines to fly from St. Louis to Chicago O'Hare Intl Airport one-way?
For one-way options, check prices for American Airlines. According to our data, you can fly for as low as $49. Users have also found prices from $56 and $69 on Southwest and Frontier, respectively.
What are the most reliable airlines from St. Louis to Chicago O'Hare Intl Airport?
Before booking your flight to Chicago O'Hare Intl Airport from St. Louis, check out the most reliable airlines to get you to your destination on time: Republic Airways (94%), Qatar Airways (85%), Aer Lingus( 85%).
What are the cheapest flights from St. Louis to Chicago O'Hare Intl Airport?
The cheapest flight price from St. Louis to Chicago O'Hare Intl Airport is $134. On average you can expect to pay $2,041. The most popular route, (Lambert-St Louis - Chicago O'Hare Intl), can usually be booked for $91.
Can I find deals for flights from St. Louis to O'Hare Intl that include hotel bookings?
Yes. In addition to deals on St. Louis to O'Hare Intl flights, Cheapflights offers vacation packages that include both flights and hotel.
How can I find direct flights from St. Louis to O'Hare Intl?
After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from St. Louis to O'Hare Intl.
Can I find deals for business class flights from St. Louis to O'Hare Intl?
Yes. Cheapflights offers flight deals from St. Louis to O'Hare Intl 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 St. Louis to Chicago O'Hare Intl Airport?
Currently, August is the cheapest month in which you can book a flight from St. Louis to Chicago O'Hare Intl Airport (average of $245). Flying from St. Louis to Chicago O'Hare Intl Airport in March is currently the most expensive (average of $321). 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.

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Top 3 airlines flying from St. Louis to O'Hare Intl

Airline	Cheapest	Average	Flexibility	On-time
American Airlines	Cheapest$115	Average$271	FlexibilityNo cancel fee	On-time71%
Southern / Mokulele	Cheapest$118	Average$190	FlexibilityNo cancel fee	On-timeN/A
United Airlines	Cheapest$133	Average$312	FlexibilityNo cancel fee	On-time69%

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$49+ Cheap flights from St. Louis (STL) to O'Hare Intl (ORD)

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 8/18. Fares are subject to change and may not be available on all flights or dates of travel.

Find cheap flights from St. Louis to O'Hare Intl with Cheapflights

1. Tell us where you want to go

2. Select your favorite providers

3. Compare prices and book

Cheapflights Tip: The best prices from Lambert-St Louis to Chicago O'Hare Intl are usually found in August or September, booked 62 days in advance, depart on a Thursday or Friday and return on a Friday

Cheap flight deals from St. Louis to O'Hare Intl

Round-trip from

One-way from

Popular in

Cheapest in

Average price

Good round-trip deal

Good one-way deal

Find flight deals from St. Louis to O'Hare Intl

Cheapest flights from St. Louis to O'Hare IntlExplore the most affordable flight options available from St. Louis to O'Hare Intl. Find the lowest fares from popular airlines and budget airlines, with prices last updated on July 3, 2025.

Explore the most affordable flight options available from St. Louis to O'Hare Intl. Find the lowest fares from popular airlines and budget airlines, with prices last updated on July 3, 2025.

Cheapflights Fare Finder

Use the filters below to find and compare flights from St. Louis to Chicago O'Hare Intl Airport that are best for you.

The best insider tips for St. Louis to Chicago O'Hare Intl Airport flights

Cheapflights partnered with top experts to bring you the best recommendations for your St. Louis to Chicago O'Hare Intl Airport trip

Airlines

Lufthansa

United Airlines

Airports

STL

ORD

Our travel experts

Best time to book a flight from St. Louis to O'Hare Intl

Have a flexible travel schedule? Discover the best time to fly to O'Hare Intl from St. Louis with our price prediction graph.

Cheapflights Insights

Everything you need to know about your flight from St. Louis to Chicago O'Hare Intl Airport

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

Use this chart to determine the optimal time to book a round-trip flight from St. Louis to O'Hare Intl. Price data was last updated on June 27, 2025.

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

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

Find hourly flight availability from St. Louis to O'Hare Intl. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated July 3, 2025.

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

Use this chart to determine the cheapest time to fly round-trip from St. Louis to O'Hare Intl. Price data was last updated on June 29, 2025.

Weekly flight availability from St. Louis to Chicago O'Hare Intl Airport

Explore weekly flight availability from St. Louis to O'Hare Intl. 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 July 3, 2025.

Reviews of airlines servicing O'Hare Intl

See what other customers who have flown with Southwest, Delta, and United Airlines from St. Louis to Chicago O'Hare Intl Airport have to say. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.

Related info for your journey

Find useful and relevant information for your journey from St. Louis to O'Hare Intl. 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 from for flights from St. Louis to Chicago O'Hare Intl?

What are the cheapest airlines flying from St. Louis to Chicago O'Hare Intl Airport round-trip?

What are the cheapest airlines to fly from St. Louis to Chicago O'Hare Intl Airport one-way?

What are the most reliable airlines from St. Louis to Chicago O'Hare Intl Airport?

What are the cheapest flights from St. Louis to Chicago O'Hare Intl Airport?

Can I find deals for flights from St. Louis to O'Hare Intl that include hotel bookings?

How can I find direct flights from St. Louis to O'Hare Intl?

Can I find deals for business class flights from St. Louis to O'Hare Intl?

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

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Alternative routes for St. Louis to O'Hare Intl

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Top 3 airlines flying from St. Louis to O'Hare Intl

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Cheapest flights from St. Louis to O'Hare Intl
Explore the most affordable flight options available from St. Louis to O'Hare Intl. Find the lowest fares from popular airlines and budget airlines, with prices last updated on July 3, 2025.