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St. Louis

$73+ Cheap flights from Illinois 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 5/29. Fares are subject to change and may not be available on all flights or dates of travel.
ORD — STL
May 6 — May 131
Tue 5/6
Tue 5/13
1 adult, Economy
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Cheap flight deals from Illinois to St. Louis

Keep the following information in mind while searching for Illinois to St. Louis flight deals. Data was last updated May 1, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$140
(Southern / Mokulele)

One-way from

$73
(Southern / Mokulele)

Popular in

March

Cheapest in

May

Average price

$233

Good round-trip deal

$213 or less

Good one-way deal

$121 or less
Provider with most accurate pricing for Chicago (CHI)-Lambert-St Louis flight deals.
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Provider most trusted by Cheapflights users for Chicago (CHI)-Lambert-St Louis flights.
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From Illinois to Lambert-St Louis
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One-way flight from Illinois to Lambert-St Louis
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Highest demand for flights based on searches. 4% potential increase in price ($13 potential increase over avg. RT price).
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Cheapest flight prices on average. 1% potential price decrease ($4 potential savings vs. average RT price).
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Average for round-trip flights in May 2025
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Price to beat on a round-trip flight from Illinois to Lambert-St Louis.
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Price to beat on a one-way flight from Illinois to Lambert-St Louis.
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Find flight deals from Illinois to St. Louis

Cheapest flights from Illinois to St. Louis
Explore the most affordable flight options available from Illinois to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on May 1, 2025.

This Southern / Mokulele deal was found by Cheapflights users on 5/1. 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 Southern / Mokulele is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/298:25 amORD - STL
1 stop11h 45mSouthern / Mokulele
Thu 6/512:15 pmSTL - ORD
1 stop3h 35mSouthern / Mokulele
Deal found 5/1$140
This Frontier deal was found by Cheapflights users on 4/30. 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.
Sat 6/146:20 amMDW - STL
1 stop7h 47mFrontier
Sat 6/212:52 pmSTL - MDW
1 stop7h 36mFrontier
Deal found 4/30$161
This Frontier deal was found by Cheapflights users on 4/30. 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.
Wed 5/285:03 pmORD - STL
1 stop6h 41mFrontier
Wed 6/45:45 pmSTL - ORD
1 stop6h 51mFrontier
Deal found 4/30$162
This CheapOair deal was found by Cheapflights users on 4/30. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/174:15 pmORD - STL
1 stop7h 51mMultiple Airlines
Mon 5/191:00 pmSTL - ORD
1 stop3h 32mMultiple Airlines
Deal found 4/30$190
This Southwest deal was found by Cheapflights users on 4/30. 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.
Sat 5/246:35 amMDW - STL
Nonstop1h 10mSouthwest
Sun 5/257:00 amSTL - MDW
Nonstop1h 05mSouthwest
Deal found 4/30$217
This American Airlines deal was found by Cheapflights users on 4/30. 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.
Sat 5/2411:47 amORD - STL
Nonstop1h 20mAmerican Airlines
Sun 5/257:30 amSTL - ORD
Nonstop1h 19mAmerican Airlines
Deal found 4/30$218
This Delta deal was found by Cheapflights users on 4/30. 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.
Sat 5/241:08 pmMDW - STL
1 stop3h 29mDelta
Sun 5/256:00 amSTL - MDW
2 stops6h 28mDelta
Deal found 4/30$242
This Delta deal was found by Cheapflights users on 4/30. 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.
Sat 5/241:45 pmORD - STL
2 stops9h 41mDelta
Sun 5/256:00 amSTL - ORD
1 stop6h 20mDelta
Deal found 4/30$242
This United Airlines deal was found by Cheapflights users on 4/30. 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.
Thu 6/1210:54 amORD - STL
Nonstop1h 26mUnited Airlines
Mon 6/165:00 amSTL - ORD
Nonstop1h 30mUnited Airlines
Deal found 4/30$263
This Southwest deal was found by Cheapflights users on 4/30. 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.
Sat 9/202:55 pmORD - STL
1 stop5h 35mSouthwest
Sat 10/41:45 pmSTL - ORD
2 stops8h 15mSouthwest
Deal found 4/30$292
This Mytrip deal was found by Cheapflights users on 5/1. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/1412:41 pmORD - STL
1 stop20h 34mSpirit Airlines
Sat 5/1710:10 amSTL - ORD
3 stops22h 45mSpirit Airlines
Deal found 5/1$294
This American Airlines deal was found by Cheapflights users on 4/30. 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.
Wed 5/1410:16 amSPI - STL
1 stop13h 35mAmerican Airlines
Wed 5/216:00 amSTL - SPI
1 stop11h 55mAmerican Airlines
Deal found 4/30$675

Cheapflights Fare Finder

Customize your flight search to find flights from Illinois 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 May 1, 2025.
Use the filters below to find and compare flights from Illinois to St. Louis that are best for you.

Fly from

Illinois

Fly to

St. Louis

Route

Depart

Return

Price

ChicagoSt. Louis

ORD - STL

ORDSTL

Chicago O'Hare Intl

Thu 5/29

8:25 am-8:10 pm

1 stop11h 45m

Lambert-St Louis

Thu 6/5

12:15 pm-3:50 pm

1 stop3h 35m

$140

ChicagoSt. Louis

MDW - STL

MDWSTL

Chicago Midway

Sat 6/14

6:20 am-2:07 pm

1 stop7h 47m

Lambert-St Louis

Sat 6/21

2:52 pm-10:28 pm

1 stop7h 36m

$161

ChicagoSt. Louis

ORD - STL

ORDSTL

Chicago O'Hare Intl

Wed 5/28

5:03 pm-11:44 pm

1 stop6h 41m

Lambert-St Louis

Wed 6/4

5:45 pm-12:36 am

1 stop6h 51m

$162

ChicagoSt. Louis

ORD - STL

ORDSTL

Chicago O'Hare Intl

Sat 5/17

4:15 pm-12:06 am

1 stop7h 51m

Lambert-St Louis

Mon 5/19

1:00 pm-4:32 pm

1 stop3h 32m

$190

ChicagoSt. Louis

MDW - STL

MDWSTL

Chicago Midway

Sat 5/24

6:35 am-7:45 am

Nonstop1h 10m

Lambert-St Louis

Sun 5/25

7:00 am-8:05 am

Nonstop1h 05m

$217

ChicagoSt. Louis

ORD - STL

ORDSTL

Chicago O'Hare Intl

Sat 5/24

8:30 am-9:51 am

Nonstop1h 21m

Lambert-St Louis

Sun 5/25

7:30 am-8:49 am

Nonstop1h 19m

$218

ChicagoSt. Louis

MDW - STL

MDWSTL

Chicago Midway

Sat 5/24

1:08 pm-4:37 pm

1 stop3h 29m

Lambert-St Louis

Sun 5/25

6:00 am-12:28 pm

2 stops6h 28m

$242

ChicagoSt. Louis

ORD - STL

ORDSTL

Chicago O'Hare Intl

Sat 5/24

1:45 pm-11:26 pm

2 stops9h 41m

Lambert-St Louis

Sun 5/25

6:00 am-12:20 pm

1 stop6h 20m

$242

ChicagoSt. Louis

ORD - STL

ORDSTL

Chicago O'Hare Intl

Thu 6/12

10:54 am-12:20 pm

Nonstop1h 26m

Lambert-St Louis

Mon 6/16

5:00 am-6:30 am

Nonstop1h 30m

$263

ChicagoSt. Louis

ORD - STL

ORDSTL

Chicago O'Hare Intl

Sat 9/20

2:55 pm-8:30 pm

1 stop5h 35m

Lambert-St Louis

Sat 10/4

1:45 pm-10:00 pm

2 stops8h 15m

$292

Flights are sorted by cheapest round-trip flights first.

Deals found on 4/30

Showing 1-10 of 26 results
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Best time to book a flight from Illinois to St. Louis

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

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

Currently, August is the cheapest month in which you can book a flight from Illinois to St. Louis (average of $311). Flying from Illinois 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 IL to STL?

Find hourly flight availability from Illinois 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 May 1, 2025.

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Illinois to St. Louis as you normally would.

Weekly flight availability from Illinois to St. Louis

Explore weekly flight availability from Illinois 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 May 1, 2025.

The most flights from USIL to STL are scheduled on a Thursday (59 on average). You will have fewer flight options on Monday, which is when the least amount of flights are scheduled (25 on average).

Rainfall in St. Louis by month

Plan your trip to St. Louis by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in St. Louis ranges from 2.2 - 4.7 inches per month. May is typically the wettest month, when rainfall can reach 4.7 in. February is typically the driest time to visit St. Louis when rainfall is around 2.2 in.

Temperature in St. Louis by month

Plan your trip to St. Louis by taking into account the average temperature totals by month.

If weather is an important factor for your trip to St. Louis, 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 80.6 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 32.0 F).

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 May 1, 2025.
Get a feel of what it's like to fly with Alaska Airlines, Southwest and Delta from Illinois to St. Louis by reading reviews from past customers. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.
Alaska Airlines
8.0
Very good
9,972 reviews

Crew

8.5

Overall

8.0

Food

7.1

Boarding

8.1

Entertainment

7.1

Comfort

7.9

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Alaska Airlines
8.0
Very good
9,972 reviews
Alaska Airlines
8.0
Very good
9,972 reviews

Crew

8.5

Overall

8.0

Food

7.1

Boarding

8.1

Entertainment

7.1

Comfort

7.9

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Southwest
8.0
Very good
4,293 reviews
Alaska Airlines
8.0
Very good
9,972 reviews

Crew

8.5

Overall

8.0

Food

7.1

Boarding

8.1

Entertainment

7.1

Comfort

7.9

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Delta
8.0
Very good
7,934 reviews
Alaska Airlines
8.0
Very good
9,972 reviews

Crew

8.5

Overall

8.0

Food

7.1

Boarding

8.1

Entertainment

7.1

Comfort

7.9

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
United Airlines
7.4
Good
8,696 reviews
Alaska Airlines
8.0
Very good
9,972 reviews

Crew

8.5

Overall

8.0

Food

7.1

Boarding

8.1

Entertainment

7.1

Comfort

7.9

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
American Airlines
7.2
Good
10,000 reviews
Alaska Airlines
8.0
Very good
9,972 reviews

Crew

8.5

Overall

8.0

Food

7.1

Boarding

8.1

Entertainment

7.1

Comfort

7.9

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.

Related info for your journey

Find useful and relevant information for your journey from Illinois 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 Illinois?

    If you book a flight to St. Louis from Illinois, 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.

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

    The cheapest airline one-way is Southern / Mokulele, with whom users have recently found tickets for as low as $73. However, be on the lookout for offers from Frontier and Southwest, as they are both options that can get you from Illinois to St. Louis for a low price.

  • What are the most popular routes from Illinois to St. Louis?

    When deciding which route to take from Illinois to St. Louis consider Chicago O'Hare Intl - Lambert-St Louis, Chicago Midway - Lambert-St Louis or Springfield Capital - Lambert-St Louis as they are the most popular.

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

    Looking for the most reliable airlines to get you to your destination on time? Our data shows these are most likely to get you from Illinois to St. Louis on time: Republic Airways (84%), Turkish Airlines (83%), Alaska Airlines (82%).

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

    Looking at all options, your cheapest flight can be booked for $48. While the most popular route (Chicago O'Hare Intl - Lambert-St Louis) can be booked for $140 on average our data indicates $342 when flying from Illinois to St. Louis.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from Illinois 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 Illinois to St. Louis?

    Currently, August is the cheapest month in which you can book a flight from Illinois to St. Louis (average of $311). Flying from Illinois 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 Illinois?

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

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Alternative routes for Illinois to St. Louis

See prices for flight routes from nearby airports that may be better suited for you.
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Top 4 airlines flying from Illinois to St. Louis

Discover the top 4 airlines that operate flights from Illinois 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 May 1, 2025.
AirlineCheapestAverageFlexibilityOn-time
American AirlinesCheapest$115Average$271FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$116Average$328FlexibilityNo cancel feeOn-time63%
Southern / MokuleleCheapest$117Average$176FlexibilityNo cancel feeOn-timeN/A
United AirlinesCheapest$141Average$319FlexibilityNo cancel feeOn-time69%

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