Southwest® flights from Portland, OR to St. Louis from $149

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Low fares from Portland, OR to St. Louis

$

Portland, OR (PDX)to

St. Louis (STL)
Depart: 09/05/2026

One-way

Basic

From
$149
Seen: 7 hrs ago

Portland, OR (PDX)to

St. Louis (STL)
Depart: 08/29/2026

One-way

Basic

From
$149
Seen: 17 hrs ago

Portland, OR (PDX)to

St. Louis (STL)
Depart: 11/04/2026

One-way

Basic

From
$159
Seen: 7 hrs ago

Portland, OR (PDX)to

St. Louis (STL)
Depart: 11/03/2026

One-way

Basic

From
$159
Seen: 5 hrs ago

Portland, OR (PDX)to

St. Louis (STL)
Depart: 09/26/2026

One-way

Basic

From
$159
Seen: 14 hrs ago

Portland, OR (PDX)to

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

One-way

Basic

From
$159
Seen: 9 hrs ago

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Explore flights from Portland, OR to St. Louis

Jul 2026
From$320*
Seen: 20 hrs ago
One Way/Basic
Aug 2026
From$149*
Seen: 17 hrs ago
One Way/Basic
Sep 2026
From$149*
Seen: 7 hrs ago
One Way/Basic
cmp-daily-histogram-bars-legend-min-price-aria-label $149
cmp-daily-histogram-bars-legend-max-price-aria-label $320
Displaying fares for July-2026
  • PDX–STL, 07/31/2026: From $320
    31

    Fri

    JUL

  • PDX–STL, 08/01/2026: From $310
    01

    Sat

  • PDX–STL, 08/02/2026: From $310
    02

    Sun

  • PDX–STL, 08/03/2026: From $320
    03

    Mon

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

    Tue

  • PDX–STL, 08/05/2026: From $320
    05

    Wed

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

    Thu

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

    Fri

  • PDX–STL, 08/08/2026: From $312
    08

    Sat

  • PDX–STL, 08/09/2026: From $312
    09

    Sun

  • PDX–STL, 08/10/2026: From $307
    10

    Mon

  • PDX–STL, 08/11/2026: From $307
    11

    Tue

  • PDX–STL, 08/12/2026: From $307
    12

    Wed

  • PDX–STL, 08/13/2026: From $204
    13

    Thu

  • PDX–STL, 08/14/2026: From $209
    14

    Fri

  • PDX–STL: cmp-view-offers-disclaimer. Find Offers
    15

    Sat

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

    Sun

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

    Mon

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

    Tue

  • PDX–STL, 08/19/2026: From $204
    19

    Wed

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

    Thu

  • PDX–STL: cmp-view-offers-disclaimer. Find Offers
    21

    Fri

  • PDX–STL: cmp-view-offers-disclaimer. Find Offers
    22

    Sat

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

    Sun

  • PDX–STL, 08/24/2026: From $175
    24

    Mon

  • PDX–STL, 08/25/2026: From $175
    25

    Tue

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

    Wed

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

    Thu

  • PDX–STL, 08/28/2026: From $175
    28

    Fri

  • PDX–STL, 08/29/2026: From $149
    29

    Sat

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

    Sun

    • Range$149-$320

    *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:
    Portland International Airport
    Arriving at:
    Lambert-St Louis Int'l Airport
    Distance:
    1708 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 Portland, OR to St. Louis on Southwest Airlines.
    To find the lowest fares by day and time to fly Portland, OR 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 Portland, OR 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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