Southwest® flights from Baltimore/Washington to St. Louis from $143

Promo Code

Low fares from Baltimore/Washington to St. Louis

$

Baltimore/Washington (BWI)to

St. Louis (STL)
Depart: 11/02/2026

One-way

Basic

From
$143
Seen: 11 hrs ago

Baltimore/Washington (BWI)to

St. Louis (STL)
Depart: 10/08/2026

One-way

Basic

From
$143
Seen: 17 hrs ago

Baltimore/Washington (BWI)to

St. Louis (STL)
Depart: 10/01/2026

One-way

Basic

From
$143
Seen: 3 hrs ago

Baltimore/Washington (BWI)to

St. Louis (STL)
Depart: 10/03/2026

One-way

Basic

From
$143
Seen: 6 hrs ago

Baltimore/Washington (BWI)to

St. Louis (STL)
Depart: 11/04/2026

One-way

Basic

From
$143
Seen: 15 hrs ago

Baltimore/Washington (BWI)to

St. Louis (STL)
Depart: 10/28/2026

One-way

Basic

From
$143
Seen: 8 hrs ago

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Explore flights from Baltimore/Washington to St. Louis

Jul 2026
From$501*
Seen: 18 hrs ago
One Way/Basic
Aug 2026
From$143*
Seen: 13 hrs ago
One Way/Basic
Sep 2026
From$143*
Seen: 10 hrs ago
One Way/Basic
cmp-daily-histogram-bars-legend-min-price-aria-label $143
cmp-daily-histogram-bars-legend-max-price-aria-label $506
Displaying fares for July-2026
  • BWI–STL, 07/31/2026: From $501
    31

    Fri

    JUL

  • BWI–STL, 08/01/2026: From $501
    01

    Sat

  • BWI–STL: cmp-view-offers-disclaimer. Find Offers
    02

    Sun

  • BWI–STL, 08/03/2026: From $501
    03

    Mon

  • BWI–STL, 08/04/2026: From $506
    04

    Tue

  • BWI–STL, 08/05/2026: From $411
    05

    Wed

  • BWI–STL, 08/06/2026: From $406
    06

    Thu

  • BWI–STL: cmp-view-offers-disclaimer. Find Offers
    07

    Fri

  • BWI–STL, 08/08/2026: From $406
    08

    Sat

  • BWI–STL, 08/09/2026: From $406
    09

    Sun

  • BWI–STL, 08/10/2026: From $411
    10

    Mon

  • BWI–STL: cmp-view-offers-disclaimer. Find Offers
    11

    Tue

  • BWI–STL, 08/12/2026: From $411
    12

    Wed

  • BWI–STL: cmp-view-offers-disclaimer. Find Offers
    13

    Thu

  • BWI–STL, 08/14/2026: From $270
    14

    Fri

  • BWI–STL, 08/15/2026: From $270
    15

    Sat

  • BWI–STL, 08/16/2026: From $270
    16

    Sun

  • BWI–STL: cmp-view-offers-disclaimer. Find Offers
    17

    Mon

  • BWI–STL: cmp-view-offers-disclaimer. Find Offers
    18

    Tue

  • BWI–STL, 08/19/2026: From $275
    19

    Wed

  • BWI–STL: cmp-view-offers-disclaimer. Find Offers
    20

    Thu

  • BWI–STL, 08/21/2026: From $169
    21

    Fri

  • BWI–STL, 08/22/2026: From $143
    22

    Sat

  • BWI–STL, 08/23/2026: From $208
    23

    Sun

  • BWI–STL, 08/24/2026: From $148
    24

    Mon

  • BWI–STL, 08/25/2026: From $148
    25

    Tue

  • BWI–STL, 08/26/2026: From $148
    26

    Wed

  • BWI–STL, 08/27/2026: From $148
    27

    Thu

  • BWI–STL, 08/28/2026: From $169
    28

    Fri

  • BWI–STL, 08/29/2026: From $143
    29

    Sat

  • BWI–STL, 08/30/2026: From $189
    30

    Sun

    • Range$143-$506

    *Fares displayed have been collected within the last 24 hours and may no longer be available at time of booking. Additional fees and charges for optional products and services may apply. Modifying this information may result in a different fare. To find the most updated fare, please visit Southwest.com. Fares listed are Basic, which are subject to additional terms and conditions.

    Flight Details

    Departing from:
    Balt./Wash. International Airport
    Arriving at:
    Lambert-St Louis Int'l Airport
    Average flight time:
    2 hours 17 minutes
    Distance:
    738 miles

    Route Information

    156† Weekly flights
    • 3‡ Nonstop flights per day Monday through Friday
    • 3‡ Nonstop flights on Saturday
    • 4‡ Nonstop flights on Sunday

    † Weekly flights based on DOT published scheduled average flights Monday through Sunday between 9/1/2025 and 9/30/2025. Note: route may not operate every day of the week.

    ‡ Nonstop flights based on DOT published scheduled average flights Monday through Sunday between 9/1/2025 and 9/30/2025.

    Questions we hear the most

    The average flight time from Baltimore/Washington to St. Louis is 2 hours 17 minutes.
    There are 156 weekly flights from Baltimore/Washington to St. Louis on Southwest Airlines.
    Yes, Southwest flies nonstop from Baltimore/Washington to St. Louis 3 times per day from Monday through Friday.
    Yes, Southwest flies nonstop from Baltimore/Washington to St. Louis 3 times per day on Saturdays and 4 times per day on Sundays.
    To find the lowest fares by day and time to fly Baltimore/Washington to St. Louis with Southwest, check out our Low Fare Calendar.
    You can rent a car at Lambert-St Louis Int'l Airport book yours with your flight.
    Yes! Flights from Baltimore/Washington to St. Louis—or from here or there to anywhere—can be changed with no change fees. Fare difference may apply.
    Check the status of your upcoming Southwest flight.
    Check out the Southwest Airlines® Help Center for answers about everything Southwest.

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