Southwest® flights from Seattle/Tacoma to St. Louis from $94

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Low fares from Seattle/Tacoma to St. Louis

$

Seattle/Tacoma (SEA)to

St. Louis (STL)
Depart: 09/02/2026

One-way

Basic

From
$94
Seen: 19 hrs ago

Seattle/Tacoma (SEA)to

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

One-way

Basic

From
$94
Seen: 16 hrs ago

Seattle/Tacoma (SEA)to

St. Louis (STL)
Depart: 09/10/2026

One-way

Basic

From
$94
Seen: 2 hrs ago

Seattle/Tacoma (SEA)to

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

One-way

Basic

From
$94
Seen: 2 hrs ago

Seattle/Tacoma (SEA)to

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

One-way

Basic

From
$94
Seen: 10 hrs ago

Seattle/Tacoma (SEA)to

St. Louis (STL)
Depart: 10/22/2026

One-way

Basic

From
$99
Seen: 16 hrs ago

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Explore flights from Seattle/Tacoma to St. Louis

Aug 2026
From$224*
Seen: 7 hrs ago
One Way/Basic
Sep 2026
From$94*
Seen: 19 hrs ago
One Way/Basic
Oct 2026
From$94*
Seen: 2 hrs ago
One Way/Basic
cmp-daily-histogram-bars-legend-min-price-aria-label $224
cmp-daily-histogram-bars-legend-max-price-aria-label $384
Displaying fares for August-2026
  • SEA–STL: cmp-view-offers-disclaimer. Find Offers
    02

    Sun

    AUG

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

    Mon

  • SEA–STL, 08/04/2026: From $384
    04

    Tue

  • SEA–STL, 08/05/2026: From $384
    05

    Wed

  • SEA–STL, 08/06/2026: From $384
    06

    Thu

  • SEA–STL, 08/07/2026: From $384
    07

    Fri

  • SEA–STL, 08/08/2026: From $344
    08

    Sat

  • SEA–STL, 08/09/2026: From $344
    09

    Sun

  • SEA–STL, 08/10/2026: From $344
    10

    Mon

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

    Tue

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

    Wed

  • SEA–STL, 08/13/2026: From $344
    13

    Thu

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

    Fri

  • SEA–STL, 08/15/2026: From $279
    15

    Sat

  • SEA–STL, 08/16/2026: From $284
    16

    Sun

  • SEA–STL, 08/17/2026: From $279
    17

    Mon

  • SEA–STL, 08/18/2026: From $279
    18

    Tue

  • SEA–STL, 08/19/2026: From $279
    19

    Wed

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

    Thu

  • SEA–STL, 08/21/2026: From $269
    21

    Fri

  • SEA–STL, 08/22/2026: From $224
    22

    Sat

  • SEA–STL, 08/23/2026: From $229
    23

    Sun

  • SEA–STL: cmp-view-offers-disclaimer. Find Offers
    24

    Mon

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

    Tue

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

    Wed

  • SEA–STL, 08/27/2026: From $224
    27

    Thu

  • SEA–STL, 08/28/2026: From $224
    28

    Fri

  • SEA–STL, 08/29/2026: From $224
    29

    Sat

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

    Sun

  • SEA–STL: cmp-view-offers-disclaimer. Find Offers
    31

    Mon

  • SEA–STL: cmp-view-offers-disclaimer. Find Offers
    01

    Tue

    SEP

    • Range$224-$384

    *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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