Southwest® flights from Phoenix to St. Louis from $128

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Low fares from Phoenix to St. Louis

$

Phoenix (PHX)to

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

One-way

Basic

From
$128
Seen: 22 hrs ago

Phoenix (PHX)to

St. Louis (STL)
Depart: 10/06/2026

One-way

Basic

From
$128
Seen: 13 hrs ago

Phoenix (PHX)to

St. Louis (STL)
Depart: 10/13/2026

One-way

Basic

From
$128
Seen: 4 hrs ago

Phoenix (PHX)to

St. Louis (STL)
Depart: 09/16/2026

One-way

Basic

From
$128
Seen: 22 minutes ago

Phoenix (PHX)to

St. Louis (STL)
Depart: 10/28/2026

One-way

Basic

From
$128
Seen: 32 minutes ago

Phoenix (PHX)to

St. Louis (STL)
Depart: 10/24/2026

One-way

Basic

From
$128
Seen: 4 minutes ago

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Explore flights from Phoenix to St. Louis

Aug 2026
From$195*
Seen: 5 hrs ago
One Way/Basic
Sep 2026
From$128*
Seen: 9 hrs ago
One Way/Basic
Oct 2026
From$128*
Seen: 23 hrs ago
One Way/Basic
cmp-daily-histogram-bars-legend-min-price-aria-label $145
cmp-daily-histogram-bars-legend-max-price-aria-label $365
Displaying fares for August-2026
  • PHX–STL: cmp-view-offers-disclaimer. Find Offers
    12

    Wed

    AUG

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

    Thu

  • PHX–STL, 08/14/2026: From $327
    14

    Fri

  • PHX–STL, 08/15/2026: From $281
    15

    Sat

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

    Sun

  • PHX–STL, 08/17/2026: From $365
    17

    Mon

  • PHX–STL, 08/18/2026: From $281
    18

    Tue

  • PHX–STL, 08/19/2026: From $281
    19

    Wed

  • PHX–STL, 08/20/2026: From $327
    20

    Thu

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

    Fri

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

    Sat

  • PHX–STL, 08/23/2026: From $327
    23

    Sun

  • PHX–STL, 08/24/2026: From $327
    24

    Mon

  • PHX–STL, 08/25/2026: From $281
    25

    Tue

  • PHX–STL, 08/26/2026: From $281
    26

    Wed

  • PHX–STL, 08/27/2026: From $315
    27

    Thu

  • PHX–STL, 08/28/2026: From $315
    28

    Fri

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

    Sat

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

    Sun

  • PHX–STL, 08/31/2026: From $195
    31

    Mon

  • PHX–STL, 09/01/2026: From $165
    01

    Tue

    SEP

  • PHX–STL, 09/02/2026: From $165
    02

    Wed

  • PHX–STL, 09/03/2026: From $175
    03

    Thu

  • PHX–STL, 09/04/2026: From $215
    04

    Fri

  • PHX–STL, 09/05/2026: From $145
    05

    Sat

  • PHX–STL, 09/06/2026: From $177
    06

    Sun

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

    Mon

  • PHX–STL, 09/08/2026: From $265
    08

    Tue

  • PHX–STL, 09/09/2026: From $165
    09

    Wed

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

    Thu

  • PHX–STL, 09/11/2026: From $145
    11

    Fri

    • Range$145-$365

    *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:
    Sky Harbor International Airport
    Arriving at:
    Lambert-St Louis Int'l Airport
    Average flight time:
    2 hours 54 minutes
    Distance:
    1262 miles

    Route Information

    156† Weekly flights
    • 4‡ Nonstop flights per day Monday through Friday
    • 4‡ Nonstop flights on Saturday
    • 4‡ Nonstop flights on Sunday

    † 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

    The average flight time from Phoenix to St. Louis is 2 hours 54 minutes.
    There are 156 weekly flights from Phoenix to St. Louis on Southwest Airlines.
    Yes, Southwest flies nonstop from Phoenix to St. Louis 4 times per day from Monday through Friday.
    Yes, Southwest flies nonstop from Phoenix to St. Louis 4 times per day on Saturdays and Sundays.
    To find the lowest fares by day and time to fly Phoenix 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 Phoenix 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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