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$63+ Cheap flights from Baltimore to St. Louis (BWI - 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 5/19. Fares are subject to change and may not be available on all flights or dates of travel.
BWI — STL
May 7 — May 141
Thu 5/7
Thu 5/14
1 adult, Economy
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Find cheap flights from Baltimore to St. Louis with Cheapflights

1. Tell us where you want to go

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Cheapflights Tip: The best prices from Baltimore/Washington to Lambert-St Louis are usually found in October or September, booked 70 days in advance, depart on a Wednesday or Thursday and return on a Tuesday

Cheap flight deals from Baltimore to St. Louis

Cheapest flights from Baltimore to St. Louis
Explore the most affordable flight options available from Baltimore to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on April 7, 2026.

This Kiwi.com deal was found by Cheapflights users on 4/5. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/59:13 pm
BWI
-
STL
1 stop12h 42m
Frontier
Wed 5/135:27 pm
STL
-
BWI
1 stop13h 16m
Frontier
Deal found 4/5$127
This Kiwi.com deal was found by Cheapflights users on 4/6. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/69:13 pm
BWI
-
STL
1 stop20h 41m
Frontier
Wed 5/135:27 pm
STL
-
BWI
1 stop13h 16m
Frontier
Deal found 4/6$128
This Kiwi.com deal was found by Cheapflights users on 4/5. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/59:13 pm
BWI
-
STL
1 stop12h 42m
Frontier
Mon 5/115:27 pm
STL
-
BWI
1 stop13h 16m
Frontier
Deal found 4/5$129
This Kiwi.com deal was found by Cheapflights users on 4/3. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/69:13 pm
BWI
-
STL
1 stop20h 41m
Frontier
Mon 5/115:27 pm
STL
-
BWI
1 stop13h 16m
Frontier
Deal found 4/3$136
This Frontier deal was found by Cheapflights users on 4/6. 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.
Fri 5/15:35 pm
BWI
-
STL
1 stop6h 44m
Frontier
Mon 5/48:23 pm
STL
-
BWI
1 stop10h 20m
Frontier
Deal found 4/6$140
This Kiwi.com deal was found by Cheapflights users on 4/7. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/139:13 pm
BWI
-
STL
1 stop20h 41m
Frontier
Wed 5/205:27 pm
STL
-
BWI
1 stop13h 16m
Frontier
Deal found 4/7$141
This CheapOair deal was found by Cheapflights users on 4/3. 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.
Fri 4/2410:32 am
BWI
-
STL
1 stop13h 47m
Frontier
Sat 5/28:23 pm
STL
-
BWI
1 stop10h 44m
Frontier
Deal found 4/3$151
This Kiwi.com deal was found by Cheapflights users on 4/5. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/59:13 pm
BWI
-
STL
1 stop12h 42m
Frontier
Thu 5/146:55 pm
STL
-
BWI
1 stop11h 48m
Frontier
Deal found 4/5$158
This Kiwi.com deal was found by Cheapflights users on 4/7. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/119:23 pm
BWI
-
STL
1 stop21h 10m
Frontier
Thu 5/146:55 pm
STL
-
BWI
1 stop11h 48m
Frontier
Deal found 4/7$159
This Frontier deal was found by Cheapflights users on 4/6. 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.
Mon 4/272:23 pm
BWI
-
STL
1 stop9h 56m
Frontier
Thu 4/3011:21 am
STL
-
BWI
1 stop4h 50m
Frontier
Deal found 4/6$160

Find flight deals from Baltimore to St. Louis

Discover tips and strategies to find the most affordable flight options for your journey from Baltimore (BWI) to St. Louis (STL). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated April 7, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$127
(Kiwi.com)

One-way from

$63
(Kiwi.com)

Popular in

December

Cheapest in

October

Average price

$393
Provider with most accurate pricing for Baltimore/Washington-Lambert-St Louis flight deals.
Search Deals
Provider most trusted by Cheapflights users for Baltimore/Washington-Lambert-St Louis flights.
Search Deals
From Baltimore/Washington to Lambert-St Louis
Search Deals
One-way flight from Baltimore/Washington to Lambert-St Louis
Search Deals
Highest demand for flights based on searches. 19% potential increase in price ($86 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease ($9 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in April 2026
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Baltimore 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 April 7, 2026.
Use the filters below to find and compare flights from Baltimore to St. Louis that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

BaltimoreSt. Louis

BWI - STL

BWISTL

Baltimore/Washington

Mon 6/1

5:00 pm-8:55 pm

1 stop4h 55m

Lambert-St Louis

Tue 6/9

1:10 pm-4:15 pm

Nonstop2h 05m

$320

BaltimoreSt. Louis

BWI - STL

BWISTL

Baltimore/Washington

Sun 5/3

6:00 pm-8:35 pm

1 stop3h 35m

Lambert-St Louis

Wed 5/6

6:45 pm-9:45 pm

Nonstop2h 00m

$344

BaltimoreSt. Louis

BWI - STL

BWISTL

Baltimore/Washington

Sun 4/12

6:55 pm-11:11 pm

1 stop5h 16m

Lambert-St Louis

Mon 4/13

9:10 am-5:33 pm

1 stop7h 23m

$351

BaltimoreSt. Louis

BWI - STL

BWISTL

Baltimore/Washington

Mon 4/13

2:00 pm-6:55 pm

1 stop5h 55m

Lambert-St Louis

Tue 4/14

8:25 am-2:00 pm

1 stop4h 35m

$351

BaltimoreSt. Louis

BWI - STL

BWISTL

Baltimore/Washington

Wed 4/15

9:25 am-12:50 pm

1 stop4h 25m

Lambert-St Louis

Thu 4/16

10:50 am-5:05 pm

2 stops5h 15m

$356

BaltimoreSt. Louis

BWI - STL

BWISTL

Baltimore/Washington

Mon 5/4

11:50 am-3:30 pm

1 stop4h 40m

Lambert-St Louis

Mon 5/11

5:00 am-8:05 am

Nonstop2h 05m

$360
Quickest round-trip

BaltimoreSt. Louis

BWI - STL

BWISTL

Baltimore/Washington

Wed 6/3

7:40 pm-9:05 pm

Nonstop2h 25m

Lambert-St Louis

Sun 6/7

8:00 pm-11:00 pm

Nonstop2h 00m

$361

BaltimoreSt. Louis

BWI - STL

BWISTL

Baltimore/Washington

Fri 5/15

10:45 am-3:25 pm

2 stops5h 40m

Lambert-St Louis

Sun 5/17

5:25 am-11:40 am

2 stops5h 15m

$361

BaltimoreSt. Louis

BWI - STL

BWISTL

Baltimore/Washington

Fri 5/29

2:00 pm-6:50 pm

1 stop5h 50m

Lambert-St Louis

Mon 6/1

4:00 pm-7:05 pm

Nonstop2h 05m

$364

BaltimoreSt. Louis

BWI - STL

BWISTL

Baltimore/Washington

Tue 5/5

3:27 pm-9:13 pm

1 stop6h 46m

Lambert-St Louis

Wed 5/6

7:45 am-2:13 pm

1 stop5h 28m

$375

Flights are sorted by cheapest round-trip flights first.

Deals found on 4/3

Showing 1-10 of 21 resultsSorted by cheapest first
1
2
3

Compare providers for flights from Baltimore to St. Louis

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Baltimore to St. Louis in April.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on Baltimore-St. Louis flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Baltimore-St. Louis flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Baltimore-St. Louis flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Baltimore-St. Louis flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Baltimore-St. Louis flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

Best time to book a flight from Baltimore to St. Louis

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

How far ahead should I book a flight from Baltimore to St. Louis?

Use this chart to determine the optimal time to book a round-trip flight from Baltimore to St. Louis. Price data was last updated on April 3, 2026.

To ensure you get the cheapest price possible for a flight from Baltimore to St. Louis, you should look to book at least 70 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 Baltimore to St. Louis?

Currently, September is the cheapest month in which you can book a flight from Baltimore to St. Louis (average of $109). Flying from Baltimore to St. Louis in March is currently the most expensive (average of $244). 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 BWI to STL?

Find hourly flight availability from Baltimore 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 April 7, 2026.

One of the essential ways to save on airfare from Baltimore to St. Louis is to remain as flexible as possible. Flights that are in the afternoon tend to be the most expensive. A flight at noon could potentially save you up to 8% on airfare.

What is the cheapest day to fly from Baltimore to St. Louis?

Use this chart to determine the cheapest time to fly round-trip from Baltimore to St. Louis. Price data was last updated on April 4, 2026.

Travelers seeking maximum savings on their Baltimore to St. Louis flight should consider departing on Wednesday afternoons when fares are most often at their lowest. Monday at noon flights should be avoided if possible as fares are typically the most expensive at this time.

How much does it cost to fly round-trip from Baltimore to St. Louis?

The best insider tips for Baltimore to St. Louis flights

AI-powered summary based on content written by travel experts. AI can make mistakes.
Cheapflights partnered with top experts to bring you the best recommendations for your Baltimore to St. Louis trip
Our travel experts
Emily Zemler

Emily Zemler

Expert on BWI

Emily is a freelance writer and book author based in London covering entertainment and travel. Her work has appeared in Los Angeles Times, Observer, and Conde Nast Traveler She has ventured to more than 40 countries and all seven continents, always in search of a great art museum. She has written extensively about hotels, luxury travel, and aviation.

Read more
Taryn White

Taryn White

Expert on STL

Taryn White is a freelance travel writer, digital creator, and travel advisor who has visited nearly 100 countries and all 50 states. She’s familiar with many airports and enjoys beach hopping, boutique hotels, spa experiences, and exploring local culture. Her work has appeared in Travel + Leisure, Condé Nast Traveler, National Geographic, Smithsonian Magazine, AFAR, and more.

Read more

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 April 7, 2026.
Peruse reviews from past customers who have flown with Southwest,Delta, andAmerican Airlines from Baltimore to St. Louis to help guide your decision. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.0
Very good
4,337 reviews

Entertainment

7.5

Food

7.0

Comfort

8.0

Overall

8.0

Boarding

8.1

Crew

8.6

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.
Southwest
8.0
Very good
4,337 reviews
Southwest
8.0
Very good
4,337 reviews

Entertainment

7.5

Food

7.0

Comfort

8.0

Overall

8.0

Boarding

8.1

Crew

8.6

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.
Delta
7.9
Good
8,387 reviews
Southwest
8.0
Very good
4,337 reviews

Entertainment

7.5

Food

7.0

Comfort

8.0

Overall

8.0

Boarding

8.1

Crew

8.6

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.
American Airlines
7.1
Good
11,552 reviews
Southwest
8.0
Very good
4,337 reviews

Entertainment

7.5

Food

7.0

Comfort

8.0

Overall

8.0

Boarding

8.1

Crew

8.6

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.
Frontier
5.7
Fair
3,000 reviews
Southwest
8.0
Very good
4,337 reviews

Entertainment

7.5

Food

7.0

Comfort

8.0

Overall

8.0

Boarding

8.1

Crew

8.6

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.

Related info for your journey

Find useful and relevant information for your journey from Baltimore to St. Louis. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • How popular is this Baltimore to St. Louis flight route?

    Flights from Baltimore/Washington to Lambert-St Louis have been viewed 17 times in the past calendar month.

  • How long is the flight from Baltimore to St. Louis?

    For as low as $320, Southwest can have you in St. Louis from Baltimore in 4h 55m. Airlines will cover a distance of 736 mi. When browsing for deals, the options you’ll see will be for both nonstop flights and flights with stops.

  • What are the cheapest airlines flying from Baltimore to St. Louis round-trip?

    Flying on Frontier is currently your cheapest option to St. Louis, with prices starting at $112. Additional round-trip tickets that might be worth considering are offered by Delta and American Airlines, with the lowest prices starting at $130 and $178, respectively. Users have found that Frontier is 68% cheaper than the other options available to this destination.

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

    The cheapest airlines for a one-way flight from Baltimore to St. Louis are Frontier ($69), American Airlines ($88), and Southwest ($103).

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

    Looking for the cheapest flight from Baltimore to St. Louis? While on average our users pay $361, our data indicates the cheapest price to be $172. The most popular route (Baltimore/Washington - Lambert-St Louis), is priced around $175.

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

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

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

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

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

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

    Currently, September is the cheapest month in which you can book a flight from Baltimore to St. Louis (average of $109). Flying from Baltimore to St. Louis in March is currently the most expensive (average of $244). 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 St. Louis?

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

Browse thousands of different options on Cheapflights for your next trip

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Top 4 airlines flying from Baltimore to St. Louis

Discover the top 4 airlines that operate flights from Baltimore 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 April 7, 2026.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$112Average$173FlexibilityNo cancel feeOn-time62%
DeltaCheapest$130Average$229FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$178Average$351FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$247Average$390FlexibilityNo cancel feeOn-time63%

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