Southwest® flights from Harlingen/South Padre Island to St. Louis from $119

Promo Code

Low fares from Harlingen/South Padre Island to St. Louis

$

Harlingen/South Padre Island (HRL)to

St. Louis (STL)
Depart: 06/09/2026

One-way

Basic

From
$119
Seen: 8 hrs ago

Harlingen/South Padre Island (HRL)to

St. Louis (STL)
Depart: 04/05/2026

One-way

Basic

From
$123
Seen: 8 minutes ago

Harlingen/South Padre Island (HRL)to

St. Louis (STL)
Depart: 06/08/2026

One-way

Basic

From
$124
Seen: 13 hrs ago

Harlingen/South Padre Island (HRL)to

St. Louis (STL)
Depart: 06/09/2026

One-way

Choice

From
$154
Seen: 8 hrs ago

Harlingen/South Padre Island (HRL)to

St. Louis (STL)
Depart: 04/05/2026

One-way

Choice

From
$158
Seen: 8 minutes ago

Harlingen/South Padre Island (HRL)to

St. Louis (STL)
Depart: 06/08/2026

One-way

Choice

From
$159
Seen: 13 hrs ago

Looking for more low-fare flights?

Check out the Low Fare Calendar to find a fare that works for you. Just choose the month you want to depart and return, and we’ll show you the best fares available.

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Explore flights from Harlingen/South Padre Island to St. Louis

Mar 2026
From$194*
Seen: 18 hrs ago
One Way/Basic
Apr 2026
From$123*
Seen: 8 minutes ago
One Way/Basic
May 2026
From$244*
Seen: 3 hrs ago
One Way/Basic
$123
$356
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    • Range$123-$356

    *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:
    Valley International Airport
    Arriving at:
    Lambert-St Louis Int'l Airport
    Distance:
    961 miles

    Route Information

    88† 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 88 weekly flights from Harlingen/South Padre Island to St. Louis on Southwest Airlines.
    To find the lowest fares by day and time to fly Harlingen/South Padre Island 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 Harlingen/South Padre Island 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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