Southwest® flights from Seattle/Tacoma to St. Louis from $69

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Low fares from Seattle/Tacoma to St. Louis

$

Seattle/Tacoma (SEA)to

St. Louis (STL)
Depart: 09/24/2026

One-way

Basic

From
$69
Seen: 4 hrs ago

Seattle/Tacoma (SEA)to

St. Louis (STL)
Depart: 10/21/2026

One-way

Basic

From
$69
Seen: 8 minutes ago

Seattle/Tacoma (SEA)to

St. Louis (STL)
Depart: 10/26/2026

One-way

Basic

From
$74
Seen: 4 hrs ago

Seattle/Tacoma (SEA)to

St. Louis (STL)
Depart: 09/25/2026

One-way

Basic

From
$86
Seen: 3 hrs ago

Seattle/Tacoma (SEA)to

St. Louis (STL)
Depart: 09/24/2026

One-way

Choice

From
$104
Seen: 4 hrs ago

Seattle/Tacoma (SEA)to

St. Louis (STL)
Depart: 10/21/2026

One-way

Choice

From
$104
Seen: 8 minutes ago

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Explore flights from Seattle/Tacoma to St. Louis

Aug 2026
From$251*
Seen: 9 hrs ago
One Way/Basic
Sep 2026
From$69*
Seen: 4 hrs ago
One Way/Basic
Oct 2026
From$69*
Seen: 9 minutes ago
One Way/Basic
cmp-daily-histogram-bars-legend-min-price-aria-label $144
cmp-daily-histogram-bars-legend-max-price-aria-label $307
Displaying fares for August-2026
  • SEA–STL, 08/22/2026: From $251
    22

    Sat

    AUG

  • SEA–STL: cmp-view-offers-disclaimer. Find Offers
    23

    Sun

  • SEA–STL, 08/24/2026: From $307
    24

    Mon

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

    Tue

  • SEA–STL, 08/26/2026: From $261
    26

    Wed

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

    Thu

  • SEA–STL, 08/28/2026: From $307
    28

    Fri

  • SEA–STL, 08/29/2026: From $251
    29

    Sat

  • SEA–STL, 08/30/2026: From $307
    30

    Sun

  • SEA–STL, 08/31/2026: From $307
    31

    Mon

  • SEA–STL, 09/01/2026: From $261
    01

    Tue

    SEP

  • SEA–STL, 09/02/2026: From $261
    02

    Wed

  • SEA–STL, 09/03/2026: From $297
    03

    Thu

  • SEA–STL: cmp-view-offers-disclaimer. Find Offers
    04

    Fri

  • SEA–STL, 09/05/2026: From $251
    05

    Sat

  • SEA–STL: cmp-view-offers-disclaimer. Find Offers
    06

    Sun

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

    Mon

  • SEA–STL: cmp-view-offers-disclaimer. Find Offers
    08

    Tue

  • SEA–STL, 09/09/2026: From $261
    09

    Wed

  • SEA–STL, 09/10/2026: From $269
    10

    Thu

  • SEA–STL, 09/11/2026: From $224
    11

    Fri

  • SEA–STL, 09/12/2026: From $215
    12

    Sat

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

    Sun

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

    Mon

  • SEA–STL, 09/15/2026: From $215
    15

    Tue

  • SEA–STL, 09/16/2026: From $215
    16

    Wed

  • SEA–STL, 09/17/2026: From $215
    17

    Thu

  • SEA–STL, 09/18/2026: From $224
    18

    Fri

  • SEA–STL, 09/19/2026: From $215
    19

    Sat

  • SEA–STL, 09/20/2026: From $224
    20

    Sun

  • SEA–STL, 09/21/2026: From $144
    21

    Mon

    • Range$144-$307

    *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:
    Seattle/Tacoma International Airport
    Arriving at:
    Lambert-St Louis Int'l Airport
    Distance:
    1709 miles

    Route Information

    145† Weekly flights

    † 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

    There are 145 weekly flights from Seattle/Tacoma to St. Louis on Southwest Airlines.
    To find the lowest fares by day and time to fly Seattle/Tacoma 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 Seattle/Tacoma 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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