Southwest® flights from St. Louis to Phoenix from $139

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Low fares from St. Louis to Phoenix

$

St. Louis (STL)to

Phoenix (PHX)
Depart: 10/31/2026

One-way

Basic

From
$139
Seen: 20 hrs ago

St. Louis (STL)to

Phoenix (PHX)
Depart: 09/30/2026

One-way

Basic

From
$139
Seen: 19 hrs ago

St. Louis (STL)to

Phoenix (PHX)
Depart: 11/18/2026

One-way

Basic

From
$139
Seen: 19 hrs ago

St. Louis (STL)to

Phoenix (PHX)
Depart: 09/29/2026

One-way

Basic

From
$139
Seen: 21 hrs ago

St. Louis (STL)to

Phoenix (PHX)
Depart: 10/24/2026

One-way

Basic

From
$139
Seen: 8 hrs ago

St. Louis (STL)to

Phoenix (PHX)
Depart: 11/10/2026

One-way

Basic

From
$139
Seen: 23 hrs ago

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Explore flights from St. Louis to Phoenix

Aug 2026
From$281*
Seen: 3 hrs ago
One Way/Basic
Sep 2026
From$139*
Seen: 17 hrs ago
One Way/Basic
Oct 2026
From$139*
Seen: 12 hrs ago
One Way/Basic
cmp-daily-histogram-bars-legend-min-price-aria-label $139
cmp-daily-histogram-bars-legend-max-price-aria-label $327
Displaying fares for August-2026
  • STL–PHX, 08/22/2026: From $281
    22

    Sat

    AUG

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

    Sun

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

    Mon

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

    Tue

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

    Wed

  • STL–PHX, 08/27/2026: From $327
    27

    Thu

  • STL–PHX, 08/28/2026: From $327
    28

    Fri

  • STL–PHX, 08/29/2026: From $281
    29

    Sat

  • STL–PHX, 08/30/2026: From $327
    30

    Sun

  • STL–PHX, 08/31/2026: From $327
    31

    Mon

  • STL–PHX, 09/01/2026: From $281
    01

    Tue

    SEP

  • STL–PHX, 09/02/2026: From $281
    02

    Wed

  • STL–PHX, 09/03/2026: From $327
    03

    Thu

  • STL–PHX, 09/04/2026: From $315
    04

    Fri

  • STL–PHX, 09/05/2026: From $203
    05

    Sat

  • STL–PHX, 09/06/2026: From $203
    06

    Sun

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

    Mon

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

    Tue

  • STL–PHX, 09/09/2026: From $203
    09

    Wed

  • STL–PHX, 09/10/2026: From $203
    10

    Thu

  • STL–PHX, 09/11/2026: From $183
    11

    Fri

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

    Sat

  • STL–PHX, 09/13/2026: From $254
    13

    Sun

  • STL–PHX, 09/14/2026: From $159
    14

    Mon

  • STL–PHX, 09/15/2026: From $139
    15

    Tue

  • STL–PHX, 09/16/2026: From $139
    16

    Wed

  • STL–PHX, 09/17/2026: From $149
    17

    Thu

  • STL–PHX, 09/18/2026: From $183
    18

    Fri

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

    Sat

  • STL–PHX, 09/20/2026: From $199
    20

    Sun

  • STL–PHX, 09/21/2026: From $159
    21

    Mon

    • Range$139-$327

    *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:
    Sky Harbor International Airport
    Average flight time:
    3 hours 19 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 St. Louis to Phoenix is 3 hours 19 minutes.
    There are 156 weekly flights from St. Louis to Phoenix on Southwest Airlines.
    Yes, Southwest flies nonstop from St. Louis to Phoenix 4 times per day from Monday through Friday.
    Yes, Southwest flies nonstop from St. Louis to Phoenix 4 times per day on Saturdays and Sundays.
    To find the lowest fares by day and time to fly St. Louis to Phoenix with Southwest, check out our Low Fare Calendar.
    You can rent a car at Sky Harbor International Airport book yours with your flight.
    Yes! Flights from St. Louis to Phoenix—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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