Southwest® flights from Seattle/Tacoma to St. Louis from $114

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Low fares from Seattle/Tacoma to St. Louis

$

Seattle/Tacoma (SEA)to

St. Louis (STL)
Depart: 11/21/2026

One-way

Basic

From
$114
Seen: 17 hrs ago

Seattle/Tacoma (SEA)to

St. Louis (STL)
Depart: 01/13/2027

One-way

Basic

From
$114
Seen: 4 hrs ago

Seattle/Tacoma (SEA)to

St. Louis (STL)
Depart: 01/26/2027

One-way

Basic

From
$114
Seen: 15 hrs ago

Seattle/Tacoma (SEA)to

St. Louis (STL)
Depart: 01/12/2027

One-way

Basic

From
$114
Seen: 18 hrs ago

Seattle/Tacoma (SEA)to

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

One-way

Basic

From
$114
Seen: 4 hrs ago

Seattle/Tacoma (SEA)to

St. Louis (STL)
Depart: 12/19/2026

One-way

Basic

From
$119
Seen: 1 hour ago

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Explore flights from Seattle/Tacoma to St. Louis

Oct 2026
From$224*
Seen: 18 hrs ago
One Way/Basic
Nov 2026
From$114*
Seen: 17 hrs ago
One Way/Basic
Dec 2026
From$114*
Seen: 4 hrs ago
One Way/Basic
cmp-daily-histogram-bars-legend-min-price-aria-label $114
cmp-daily-histogram-bars-legend-max-price-aria-label $294
Displaying fares for October-2026
  • SEA–STL: cmp-view-offers-disclaimer. Find Offers
    22

    Thu

    OCT

  • SEA–STL, 10/23/2026: From $263
    23

    Fri

  • SEA–STL, 10/24/2026: From $224
    24

    Sat

  • SEA–STL, 10/25/2026: From $263
    25

    Sun

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

    Mon

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

    Tue

  • SEA–STL, 10/28/2026: From $224
    28

    Wed

  • SEA–STL: cmp-view-offers-disclaimer. Find Offers
    29

    Thu

  • SEA–STL, 10/30/2026: From $263
    30

    Fri

  • SEA–STL, 10/31/2026: From $224
    31

    Sat

  • SEA–STL, 11/01/2026: From $263
    01

    Sun

    NOV

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

    Mon

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

    Tue

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

    Wed

  • SEA–STL, 11/05/2026: From $263
    05

    Thu

  • SEA–STL, 11/06/2026: From $263
    06

    Fri

  • SEA–STL, 11/07/2026: From $219
    07

    Sat

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

    Sun

  • SEA–STL, 11/09/2026: From $129
    09

    Mon

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

    Tue

  • SEA–STL, 11/11/2026: From $135
    11

    Wed

  • SEA–STL, 11/12/2026: From $216
    12

    Thu

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

    Fri

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

    Sat

  • SEA–STL, 11/15/2026: From $294
    15

    Sun

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

    Mon

  • SEA–STL: cmp-view-offers-disclaimer. Find Offers
    17

    Tue

  • SEA–STL: cmp-view-offers-disclaimer. Find Offers
    18

    Wed

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

    Thu

  • SEA–STL, 11/20/2026: From $198
    20

    Fri

  • SEA–STL, 11/21/2026: From $114
    21

    Sat

    • Range$114-$294

    *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

    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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