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Find low faresSouthwest® flights from St. Louis to Harlingen/South Padre Island from $124
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1 Passenger
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Low fares from St. Louis to Harlingen/South Padre Island
$
St. Louis (STL)to
Harlingen/South Padre Island (HRL)
Depart: 03/04/2026
One-way
Basic
From
$124
Seen: 9 hrs ago
St. Louis (STL)to
Harlingen/South Padre Island (HRL)
Depart: 03/03/2026
One-way
Basic
From
$124
Seen: 9 hrs ago
St. Louis (STL)to
Harlingen/South Padre Island (HRL)
Depart: 03/17/2026
One-way
Basic
From
$124
Seen: 12 hrs ago
St. Louis (STL)to
Harlingen/South Padre Island (HRL)
Depart: 03/06/2026
One-way
Basic
From
$124
Seen: 12 hrs ago
St. Louis (STL)to
Harlingen/South Padre Island (HRL)
Depart: 03/09/2026
One-way
Basic
From
$140
Seen: 9 hrs ago
St. Louis (STL)to
Harlingen/South Padre Island (HRL)
Depart: 02/28/2026
One-way
Basic
From
$140
Seen: 8 minutes ago
Explore flights from St. Louis to Harlingen/South Padre Island
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Flight Details
Departing from:
Lambert-St Louis Int'l Airport
Arriving at:
Valley International Airport
Distance:
961 miles
Route Information
95† 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 95 weekly flights from St. Louis to Harlingen/South Padre Island on Southwest Airlines.
To find the lowest fares by day and time to fly St. Louis to Harlingen/South Padre Island with Southwest, check out our Low Fare Calendar.
You can rent a car at Valley International Airport book yours with your flight.
Yes! Flights from St. Louis to Harlingen/South Padre Island—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.