Southwest® flights from St. Louis to Portland, ME from $135

Promo Code

Low fares from St. Louis to Portland, ME

$

St. Louis (STL)to

Portland, ME (PWM)
Depart: 06/10/2026

One-way

Basic

From
$135
Seen: 21 hrs ago

St. Louis (STL)to

Portland, ME (PWM)
Depart: 06/01/2026

One-way

Basic

From
$167
Seen: 19 hrs ago

St. Louis (STL)to

Portland, ME (PWM)
Depart: 06/10/2026

One-way

Choice

From
$182
Seen: 21 hrs ago

St. Louis (STL)to

Portland, ME (PWM)
Depart: 06/04/2026

One-way

Basic

From
$187
Seen: 17 hrs ago

St. Louis (STL)to

Portland, ME (PWM)
Depart: 07/22/2026

One-way

Basic

From
$200
Seen: 21 hrs ago

St. Louis (STL)to

Portland, ME (PWM)
Depart: 06/23/2026

One-way

Basic

From
$205
Seen: 2 hrs ago

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Explore flights from St. Louis to Portland, ME

Apr 2026
From$419*
Seen: 7 hrs ago
One Way/Basic
May 2026
From$225*
Seen: 21 hrs ago
One Way/Basic
Jun 2026
From$135*
Seen: 21 hrs ago
One Way/Basic
$225
$509
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    • Range$225-$509

    *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:
    Portland International Jetport
    Distance:
    1096 miles

    Route Information

    83† 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 83 weekly flights from St. Louis to Portland, ME on Southwest Airlines.
    To find the lowest fares by day and time to fly St. Louis to Portland, ME with Southwest, check out our Low Fare Calendar.
    You can rent a car at Portland International Jetport book yours with your flight.
    Yes! Flights from St. Louis to Portland, ME—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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