Southwest® flights from St. Louis to Seattle/Tacoma from $104

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Low fares from St. Louis to Seattle/Tacoma

$

St. Louis (STL)to

Seattle/Tacoma (SEA)
Depart: 09/27/2026

One-way

Basic

From
$104
Seen: 23 hrs ago

St. Louis (STL)to

Seattle/Tacoma (SEA)
Depart: 11/07/2026

One-way

Basic

From
$104
Seen: 4 hrs ago

St. Louis (STL)to

Seattle/Tacoma (SEA)
Depart: 11/17/2026

One-way

Basic

From
$109
Seen: 11 hrs ago

St. Louis (STL)to

Seattle/Tacoma (SEA)
Depart: 09/22/2026

One-way

Basic

From
$109
Seen: 7 hrs ago

St. Louis (STL)to

Seattle/Tacoma (SEA)
Depart: 11/04/2026

One-way

Basic

From
$109
Seen: 10 hrs ago

St. Louis (STL)to

Seattle/Tacoma (SEA)
Depart: 09/29/2026

One-way

Basic

From
$109
Seen: 4 hrs ago

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Explore flights from St. Louis to Seattle/Tacoma

Aug 2026
From$261*
Seen: 4 hrs ago
One Way/Basic
Sep 2026
From$104*
Seen: 23 hrs ago
One Way/Basic
Oct 2026
From$109*
Seen: 48 minutes ago
One Way/Basic
cmp-daily-histogram-bars-legend-min-price-aria-label $114
cmp-daily-histogram-bars-legend-max-price-aria-label $357
Displaying fares for August-2026
  • STL–SEA, 08/22/2026: From $261
    22

    Sat

    AUG

  • STL–SEA, 08/23/2026: From $307
    23

    Sun

  • STL–SEA, 08/24/2026: From $357
    24

    Mon

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

    Tue

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

    Wed

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

    Thu

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

    Fri

  • STL–SEA, 08/29/2026: From $261
    29

    Sat

  • STL–SEA, 08/30/2026: From $297
    30

    Sun

  • STL–SEA, 08/31/2026: From $297
    31

    Mon

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

    Tue

    SEP

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

    Wed

  • STL–SEA, 09/03/2026: From $312
    03

    Thu

  • STL–SEA, 09/04/2026: From $330
    04

    Fri

  • STL–SEA: cmp-view-offers-disclaimer. Find Offers
    05

    Sat

  • STL–SEA, 09/06/2026: From $269
    06

    Sun

  • STL–SEA, 09/07/2026: From $279
    07

    Mon

  • STL–SEA, 09/08/2026: From $261
    08

    Tue

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

    Wed

  • STL–SEA: cmp-view-offers-disclaimer. Find Offers
    10

    Thu

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

    Fri

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

    Sat

  • STL–SEA, 09/13/2026: From $224
    13

    Sun

  • STL–SEA, 09/14/2026: From $215
    14

    Mon

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

    Tue

  • STL–SEA: cmp-view-offers-disclaimer. Find Offers
    16

    Wed

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

    Thu

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

    Fri

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

    Sat

  • STL–SEA, 09/20/2026: From $260
    20

    Sun

  • STL–SEA, 09/21/2026: From $114
    21

    Mon

    • Range$114-$357

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

    Route Information

    151† 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 151 weekly flights from St. Louis to Seattle/Tacoma on Southwest Airlines.
    To find the lowest fares by day and time to fly St. Louis to Seattle/Tacoma with Southwest, check out our Low Fare Calendar.
    You can rent a car at Seattle/Tacoma International Airport book yours with your flight.
    Yes! Flights from St. Louis to Seattle/Tacoma—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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