$100 Cheap Flights from Baltimore (BWI) to St. Louis (STL)

View $100 flight on Tue, May 20, 2025Opens in a new window

Popular airlines from Baltimore Washington Intl. Airport (BWI) to St. Louis Lambert Intl. Airport (STL)

  • Plan, book, fly with confidence

  • trending down icon
    Be in the know
    Get alerts if flight prices drop or rise*
  • bex rewards loyalty icon
    Book smarter
    Save up to 30% on select hotels after you book a flight*
  • one key icon
    Earn twice
    Earn your airline miles on top of our OneKeyCash
    Learn about One Key
Find available prices by choosing your travel dates.

Cheap Flights from Baltimore to St. Louis (BWI-STL)

Prices were available within the past 7 days and start at $100 for one-way flights and $188 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Frontier Airlines
Tue, Apr 29 - Tue, May 13
BWI
Baltimore
STL
St. Louis
$188 Roundtrip, found 9 hours ago
$188
Roundtrip
found 9 hours ago
Select Frontier Airlines flight, departing Tue, Apr 29 from Baltimore to St. Louis, returning Tue, May 13, priced at $188 found 9 hours ago
Spirit Airlines
Sun, May 4 - Sat, May 10
BWI
Baltimore
STL
St. Louis
$201 Roundtrip, found 5 days ago
$201
Roundtrip
found 5 days ago
Select Spirit Airlines flight, departing Sun, May 4 from Baltimore to St. Louis, returning Sat, May 10, priced at $201 found 5 days ago
Spirit Airlines
Sun, May 4 - Sat, May 10
BWI
Baltimore
STL
St. Louis
$203 Roundtrip, found 5 days ago
$203
Roundtrip
found 5 days ago
Select Spirit Airlines flight, departing Sun, May 4 from Baltimore to St. Louis, returning Sat, May 10, priced at $203 found 5 days ago
Frontier Airlines
Sat, May 24 - Sat, Jun 7
BWI
Baltimore
STL
St. Louis
$204 Roundtrip, found 3 days ago
$204
Roundtrip
found 3 days ago
Select Frontier Airlines flight, departing Sat, May 24 from Baltimore to St. Louis, returning Sat, Jun 7, priced at $204 found 3 days ago
Frontier Airlines
Sun, Apr 27 - Fri, May 16
BWI
Baltimore
STL
St. Louis
$208 Roundtrip, found 9 hours ago
$208
Roundtrip
found 9 hours ago
Select Frontier Airlines flight, departing Sun, Apr 27 from Baltimore to St. Louis, returning Fri, May 16, priced at $208 found 9 hours ago
Delta
Thu, May 15 - Sat, May 17
BWI
Baltimore
STL
St. Louis
$215 Roundtrip, found 1 hour ago
$215
Roundtrip
found 1 hour ago
Select Delta flight, departing Thu, May 15 from Baltimore to St. Louis, returning Sat, May 17, priced at $215 found 1 hour ago
Frontier Airlines
Tue, Apr 29 - Mon, May 12
BWI
Baltimore
STL
St. Louis
$218 Roundtrip, found 9 hours ago
$218
Roundtrip
found 9 hours ago
Select Frontier Airlines flight, departing Tue, Apr 29 from Baltimore to St. Louis, returning Mon, May 12, priced at $218 found 9 hours ago
Frontier Airlines
Wed, Jun 4 - Sat, Jun 14
BWI
Baltimore
STL
St. Louis
$221 Roundtrip, found 14 hours ago
$221
Roundtrip
found 14 hours ago
Select Frontier Airlines flight, departing Wed, Jun 4 from Baltimore to St. Louis, returning Sat, Jun 14, priced at $221 found 14 hours ago
Southwest Airlines
Thu, May 15 - Sat, May 17
BWI
Baltimore
STL
St. Louis
$228 Roundtrip, found 1 hour ago
$228
Roundtrip
found 1 hour ago
Select Southwest Airlines flight, departing Thu, May 15 from Baltimore to St. Louis, returning Sat, May 17, priced at $228 found 1 hour ago
United
Tue, Jun 10 - Wed, Jun 11
BWI
Baltimore
STL
St. Louis
$235 Roundtrip, found 1 day ago
$235
Roundtrip
found 1 day ago
Select United flight, departing Tue, Jun 10 from Baltimore to St. Louis, returning Wed, Jun 11, priced at $235 found 1 day ago

Frequently asked questions

How much does a flight from Baltimore Washington Intl. Thurgood Marshall Airport (BWI) to Lambert-St. Louis Intl. Airport (STL) cost?
You’ll find affordable return tickets from Baltimore Washington Intl. Thurgood Marshall Airport (BWI) to Lambert-St. Louis Intl. Airport (STL) starting from $221. Grab your seat and set off on your next adventure. This information is based on the cheapest price found on Expedia for this return journey departing within the next three months. This airfare is for a Southwest Airlines flight leaving BWI on May 21 2025 and touching down at STL. The price was last updated on April 24 2025 and has not changed since.
What is the cheapest month to fly from BWI to STL?
The cheapest flights from BWI to STL are usually during off-peak season, when demand is lower. To save money, avoid flying during public holidays, school breaks and major local events.
Which airlines fly direct from Baltimore Washington Intl. Thurgood Marshall Airport (BWI) to Lambert-St. Louis Intl. Airport (STL)?
You can fly directly from Baltimore Washington Intl. Thurgood Marshall Airport (BWI) to Lambert-St. Louis Intl. Airport (STL) on a Southwest Airlines flight.
What is the cheapest airline that flies from BWI to STL?
At the moment, the cheapest airline offering one-way flights from BWI to STL is Southwest Airlines. You can take off on this route from $132. This fare is based on the lowest price found on Expedia departing within the next three months. The flight takes off from BWI on June 11 2025. Prices were last updated on April 24 2025 and have not changed since.
How many flights per day from Baltimore Washington Intl. Thurgood Marshall Airport (BWI) to Lambert-St. Louis Intl. Airport (STL)?
With, on average, 2 nonstop flights that operate from Baltimore Washington Intl. Thurgood Marshall Airport (BWI) to Lambert-St. Louis Intl. Airport (STL) every day, you’ll be on your way in no time.
What are the most popular departure times for flights from Baltimore Washington Intl. Thurgood Marshall Airport (BWI) to Lambert-St. Louis Intl. Airport (STL)?
Flights between BWI and STL tend to be busiest at 6 AM. If you’re after a quieter experience and possibly cheaper fares, choose a time outside the usual busy windows.
What day of the week has the most flights from BWI to STL?
If you fly on a Friday, you’ll get the biggest range of options for flights from Baltimore Washington Intl. Thurgood Marshall Airport (BWI) to Lambert-St. Louis Intl. Airport (STL).
What is the earliest flight from Baltimore Washington Intl. Thurgood Marshall Airport (BWI) to Lambert-St. Louis Intl. Airport (STL)?
The first flight of the day out of Baltimore Washington Intl. Thurgood Marshall Airport (BWI) is at around 6:30AM UTC-5. Board this flight and you’ll reach Lambert-St. Louis Intl. Airport (STL) at approximately 8:05AM UTC-6. The overall travel time is 2h 35m.
How long does it take to fly from Baltimore Washington Intl. Thurgood Marshall Airport (BWI) to Lambert-St. Louis Intl. Airport (STL)?
Flights from BWI to STL have an average travel time of 2 hours and 29 minutes. The total distance between the two is 740 mi.
What is the best time to fly from Baltimore Washington Intl. Thurgood Marshall Airport (BWI) to Lambert-St. Louis Intl. Airport (STL)?
To avoid potential delays on the Baltimore Washington Intl. Thurgood Marshall Airport (BWI) to Lambert-St. Louis Intl. Airport (STL) route, aim to travel before 3 PM. Departures after this hour have a 22% higher chance of being canceled.**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 St. Louis from Baltimore Washington Intl. Thurgood Marshall Airport (BWI)?
Lambert-St. Louis Intl. Airport (STL) is the only airport in 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 Lambert-St. Louis Intl. Airport (STL) last-minute?
Waiting until just before your departure to book your flight from BWI to STL generally means paying more. While you may find some last-minute offers, they’re not always guaranteed. Keep your travel schedule open to maximize your chances of getting a bargain.
Is it cheaper to book a BWI to STL flight and hotel package?
Compared with arranging hotels and flights separately, booking a BWI to STL flight and hotel package with Expedia could result in significant savings. Better still, having everything in one place will take the hassle out of planning your trip. Simply secure your flights and select from our extensive range of hotels, then personalize your trip with extras like activities and car rentals.
Can I cancel or change the date of my flight from Baltimore Washington Intl. Thurgood Marshall Airport (BWI) to Lambert-St. Louis Intl. Airport (STL)?
Generally, it’s possible to cancel or reschedule your BWI to STL flight. However, for bookings made more than 24 hours ago, additional charges may apply. Refer to your airline’s policies in your itinerary to see what changes are possible and if any costs are involved. You’ll also find more details on our Customer Service portal.
*Available to One Key members.