Southwest® flights from Boston to St. Louis from $157

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Low fares from Boston to St. Louis

$

Boston (BOS)to

St. Louis (STL)
Depart: 09/04/2026

One-way

Basic

From
$157
Seen: 19 minutes ago

Boston (BOS)to

St. Louis (STL)
Depart: 09/05/2026

One-way

Basic

From
$159
Seen: 17 hrs ago

Boston (BOS)to

St. Louis (STL)
Depart: 09/11/2026

One-way

Basic

From
$159
Seen: 6 hrs ago

Boston (BOS)to

St. Louis (STL)
Depart: 08/26/2026

One-way

Basic

From
$185
Seen: 18 hrs ago

Boston (BOS)to

St. Louis (STL)
Depart: 09/22/2026

One-way

Basic

From
$185
Seen: 15 hrs ago

Boston (BOS)to

St. Louis (STL)
Depart: 09/17/2026

One-way

Basic

From
$185
Seen: 14 hrs ago

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Explore flights from Boston to St. Louis

Aug 2026
From$185*
Seen: 18 hrs ago
One Way/Basic
Sep 2026
From$157*
Seen: 19 minutes ago
One Way/Basic
Oct 2026
From$185*
Seen: 13 hrs ago
One Way/Basic
cmp-daily-histogram-bars-legend-min-price-aria-label $185
cmp-daily-histogram-bars-legend-max-price-aria-label $415
Displaying fares for August-2026
  • BOS–STL, 08/01/2026: From $281
    01

    Sat

    AUG

  • BOS–STL, 08/02/2026: From $340
    02

    Sun

  • BOS–STL, 08/03/2026: From $330
    03

    Mon

  • BOS–STL, 08/04/2026: From $281
    04

    Tue

  • BOS–STL, 08/05/2026: From $291
    05

    Wed

  • BOS–STL, 08/06/2026: From $340
    06

    Thu

  • BOS–STL, 08/07/2026: From $415
    07

    Fri

  • BOS–STL, 08/08/2026: From $314
    08

    Sat

  • BOS–STL, 08/09/2026: From $345
    09

    Sun

  • BOS–STL, 08/10/2026: From $282
    10

    Mon

  • BOS–STL, 08/11/2026: From $281
    11

    Tue

  • BOS–STL: cmp-view-offers-disclaimer. Find Offers
    12

    Wed

  • BOS–STL, 08/13/2026: From $267
    13

    Thu

  • BOS–STL: cmp-view-offers-disclaimer. Find Offers
    14

    Fri

  • BOS–STL, 08/15/2026: From $277
    15

    Sat

  • BOS–STL, 08/16/2026: From $291
    16

    Sun

  • BOS–STL, 08/17/2026: From $291
    17

    Mon

  • BOS–STL, 08/18/2026: From $281
    18

    Tue

  • BOS–STL, 08/19/2026: From $281
    19

    Wed

  • BOS–STL, 08/20/2026: From $291
    20

    Thu

  • BOS–STL, 08/21/2026: From $211
    21

    Fri

  • BOS–STL, 08/22/2026: From $185
    22

    Sat

  • BOS–STL, 08/23/2026: From $264
    23

    Sun

  • BOS–STL, 08/24/2026: From $185
    24

    Mon

  • BOS–STL: cmp-view-offers-disclaimer. Find Offers
    25

    Tue

  • BOS–STL, 08/26/2026: From $185
    26

    Wed

  • BOS–STL: cmp-view-offers-disclaimer. Find Offers
    27

    Thu

  • BOS–STL, 08/28/2026: From $211
    28

    Fri

  • BOS–STL, 08/29/2026: From $185
    29

    Sat

  • BOS–STL: cmp-view-offers-disclaimer. Find Offers
    30

    Sun

  • BOS–STL, 08/31/2026: From $185
    31

    Mon

    • Range$185-$415

    *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:
    Logan International Airport
    Arriving at:
    Lambert-St Louis Int'l Airport
    Average flight time:
    3 hours 3 minutes
    Distance:
    1047 miles

    Route Information

    149† Weekly flights
    • 3‡ Nonstop flights per day Monday through Friday
    • 3‡ Nonstop flights on Saturday
    • 3‡ 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 Boston to St. Louis is 3 hours 3 minutes.
    There are 149 weekly flights from Boston to St. Louis on Southwest Airlines.
    Yes, Southwest flies nonstop from Boston to St. Louis 3 times per day from Monday through Friday.
    Yes, Southwest flies nonstop from Boston to St. Louis 3 times per day on Saturdays and Sundays.
    To find the lowest fares by day and time to fly Boston 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 Boston 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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