Southwest® flights from Boston to St. Louis from $149

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Low fares from Boston to St. Louis

$

Boston (BOS)to

St. Louis (STL)
Depart: 10/20/2026

One-way

Basic

From
$149
Seen: 19 hrs ago

Boston (BOS)to

St. Louis (STL)
Depart: 10/06/2026

One-way

Basic

From
$149
Seen: 8 hrs ago

Boston (BOS)to

St. Louis (STL)
Depart: 12/17/2026

One-way

Basic

From
$149
Seen: 22 hrs ago

Boston (BOS)to

St. Louis (STL)
Depart: 10/07/2026

One-way

Basic

From
$149
Seen: 12 hrs ago

Boston (BOS)to

St. Louis (STL)
Depart: 12/12/2026

One-way

Basic

From
$149
Seen: 11 hrs ago

Boston (BOS)to

St. Louis (STL)
Depart: 11/12/2026

One-way

Basic

From
$149
Seen: 10 hrs ago

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Explore flights from Boston to St. Louis

Sep 2026
From$291*
Seen: 9 hrs ago
One Way/Basic
Oct 2026
From$149*
Seen: 12 hrs ago
One Way/Basic
Nov 2026
From$149*
Seen: 21 hrs ago
One Way/Basic
cmp-daily-histogram-bars-legend-min-price-aria-label $149
cmp-daily-histogram-bars-legend-max-price-aria-label $350
Displaying fares for September-2026
  • BOS–STL, 09/11/2026: From $340
    11

    Fri

    SEP

  • BOS–STL, 09/12/2026: From $301
    12

    Sat

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

    Sun

  • BOS–STL, 09/14/2026: From $340
    14

    Mon

  • BOS–STL, 09/15/2026: From $291
    15

    Tue

  • BOS–STL, 09/16/2026: From $291
    16

    Wed

  • BOS–STL, 09/17/2026: From $350
    17

    Thu

  • BOS–STL, 09/18/2026: From $340
    18

    Fri

  • BOS–STL: cmp-view-offers-disclaimer. Find Offers
    19

    Sat

  • BOS–STL, 09/20/2026: From $340
    20

    Sun

  • BOS–STL, 09/21/2026: From $340
    21

    Mon

  • BOS–STL, 09/22/2026: From $291
    22

    Tue

  • BOS–STL, 09/23/2026: From $291
    23

    Wed

  • BOS–STL, 09/24/2026: From $301
    24

    Thu

  • BOS–STL, 09/25/2026: From $301
    25

    Fri

  • BOS–STL: cmp-view-offers-disclaimer. Find Offers
    26

    Sat

  • BOS–STL, 09/27/2026: From $316
    27

    Sun

  • BOS–STL, 09/28/2026: From $311
    28

    Mon

  • BOS–STL, 09/29/2026: From $301
    29

    Tue

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

    Wed

  • BOS–STL, 10/01/2026: From $149
    01

    Thu

    OCT

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

    Fri

  • BOS–STL: cmp-view-offers-disclaimer. Find Offers
    03

    Sat

  • BOS–STL, 10/04/2026: From $291
    04

    Sun

  • BOS–STL, 10/05/2026: From $159
    05

    Mon

  • BOS–STL, 10/06/2026: From $149
    06

    Tue

  • BOS–STL, 10/07/2026: From $149
    07

    Wed

  • BOS–STL, 10/08/2026: From $179
    08

    Thu

  • BOS–STL, 10/09/2026: From $350
    09

    Fri

  • BOS–STL, 10/10/2026: From $293
    10

    Sat

    • Range$149-$350

    *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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