Cheap Flights from Baltimore (BWI) to St. Louis (CPS)

Popular airlines from Baltimore Washington Intl. Airport (BWI) to St. Louis, MO (CPS-St. Louis Downtown)

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Alternative airports near St. Louis

Prices were available within the past 7 days. Prices and availability are subject to change.

Select flight to Lambert-St. Louis Intl. STL. Cheapest option available. Average driving time to city center is 20 minutes. Flights from $187
STL
Lambert-St. Louis Intl.
Cheapest
Average driving time to city center20 min
Flights from $187
Flights from Baltimore (BWI) to St. Louis (CPS)
Origin airport
Baltimore Washington Intl. Thurgood Marshall
Destination airport
St. Louis Downtown
Distance
726 mi

Baltimore to St. Louis Flights

The cheapest times to fly from Baltimore to St. Louis

On average, Thursday can be the cheapest time to fly, according to data from the Airlines Reporting Corporation (ARC), one of the world's biggest databases for global airline sales. The data reveals that you could save up to 16% by flying on a Thursday—the cheapest day to travel on average—instead of a Sunday—the most expensive. Some of the most affordable flights from Baltimore to St. Louis are during the month of . You can find some of the cheapest flights from Baltimore to St. Louis with Expedia's search tool and vast selection of airlines.

 

The best time to book a flight from Baltimore to St. Louis

Sunday is one of the best days to book for cheap flights from Baltimore to St. Louis: Tickets reserved on a Sunday cost between 6% and 13% less than those reserved on a Friday, according to ARC data. The data also suggests booking early can also lead to cheaper airfares. You could save 24% by buying your tickets for domestic flights at least a month in advance and 10% by booking international flights 2 months in advance.

 

How to find cheap round-trip tickets from Baltimore to St. Louis

Being flexible with your dates and using Expedia's Price Drop Protection and Price Tracking features are some of the best ways of finding a cheap ticket from Baltimore to St. Louis in 2025. You can also book with separate airlines for your outbound and return journeys, from one-way. Expedia also offers Price Drop Protection, so if the cost of your airfare goes down after booking, you'll receive a credit for the difference*. This is available for a small fee, and is free to One Key Gold and Platinum tier members.

 

Expedia's Price Tracking feature means you can stay on top of airfares without manually checking every day. It sends you automated price alerts for cheap Baltimore to St. Louis flights and uses historical data to indicate when the best time to book is. Download Expedia's free app to activate this handy tool in a few easy taps.

 

You could also save big by booking one of Expedia's vacation packages. Bundling together your Baltimore to St. Louis airfare with your accommodations and car rental is often cheaper than booking everything separately. There’s also One Key, Expedia's generous rewards program. Join for free and you could earn One Key cash on most bookings to save on future adventures.

 

*Terms apply.

 

Disclaimer: ARC The statistics are based on average round-trip ticket prices between January and August 2023. The percentages you see are averages.

 

Frequently asked questions

How much does a flight from Baltimore Washington Intl. Thurgood Marshall Airport (BWI) to St. Louis Downtown Airport (CPS) cost?
Discover the latest flight deals from BWI to CPS by entering your preferred travel dates and searching on Expedia. Easily compare prices by departure date if you have flexibility with your schedule and use handy filters to explore prices for your preferred journey. As a member of One Key™, our free loyalty program, you can use Price Tracking to watch fares and receive notifications if prices go up or down.
What is the cheapest month to fly from BWI to CPS?
The cheapest flights from BWI to CPS are usually during off-peak season, when demand is lower. To save money, avoid flying during public holidays, school breaks and major local events.
What is the cheapest airline that flies from BWI to CPS?
Use the filter tool on Expedia to compare airlines and find the cheapest carrier that'll take you from BWI to CPS. Sort your results by "Price (lowest to highest)" to snap up a great deal.
How many flights per day from Baltimore Washington Intl. Thurgood Marshall Airport (BWI) to St. Louis Downtown Airport (CPS)?
You'll need to take a flight with a layover if you're traveling from Baltimore Washington Intl. Thurgood Marshall Airport (BWI) to St. Louis Downtown Airport (CPS). There are no daily direct flights on this route. However, simply filter your search to include one or more stops to find an option that works for you.
What day of the week has the most flights from BWI to CPS?
You'll usually find Tuesday the quietest day for flights, while Fridays are often the busiest.* However this can vary from season to season and during public holidays or peak travel times.*Busiest/quietest day to travel is based on Expedia flight demand through January to December 2024.
What is the best time to fly from Baltimore Washington Intl. Thurgood Marshall Airport (BWI) to St. Louis Downtown Airport (CPS)?
Opt for a flight from Baltimore Washington Intl. Thurgood Marshall Airport (BWI) to St. Louis Downtown Airport (CPS) that leaves before 3 PM to reduce the likelihood of delays and cancellations. Departures after this hour have a 22% higher chance of being canceled, on average.**Most reliable time of the day and month to travel recommendation is based on January through August 2024 flight status data sourced from OAG's global flight data platform.
What airports do you fly into for East St. Louis from Baltimore Washington Intl. Thurgood Marshall Airport (BWI)?
Lambert-St. Louis Intl. Airport (STL) is the only airport in East St. Louis with direct flights from Baltimore Washington Intl. Thurgood Marshall Airport (BWI). Check out the available options and find affordable fares on Expedia.
Is it cheaper to buy a plane ticket from Baltimore Washington Intl. Thurgood Marshall Airport (BWI) to St. Louis Downtown Airport (CPS) last-minute?
Last-minute bookings from BWI to CPS are generally more expensive. To secure the lowest rates, start searching for flights well ahead of time. That being said, if you're flexible with your travel plans, you may score a cheap ticket right before your trip.
Is it cheaper to book a BWI to CPS flight and hotel package?
Securing a BWI to CPS flight and hotel package tends to be cheaper than booking separately. With Expedia, you can enjoy the ease of organizing your trip in one place. Choose from our wide range of hotels and then add activities, flights and car rentals to your booking. Bundle it all together, and you could save hundreds of dollars.
Can I cancel or change the date of my flight from Baltimore Washington Intl. Thurgood Marshall Airport (BWI) to St. Louis Downtown Airport (CPS)?
If you reserved your BWI to CPS flight in the last 24 hours, you may be able to cancel or modify it without any fees. Depending on the airline and the type of ticket you purchased, additional charges may apply for changes beyond that time. Airline policies and contact information can be found in your itinerary or confirmation email. Or, visit our Customer Service portal if you'd like more information.

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St. Louis nearby Airports

St. Louis

Baltimore to Lambert-St. Louis Intl.
$170.81
*Available to One Key members.