$100 Cheap Flights from St. Louis (STL) to Harlingen (HRL)

Find available prices by choosing your travel dates.

Cheap Flights from St. Louis to Harlingen (STL-HRL)

Prices were available within the past 7 days and start at $100 for one-way flights and $224 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

American Airlines
United
Southwest Airlines
Southwest Airlines
United
United
United
United
Delta
American Airlines
Flights from St. Louis (STL) to Harlingen (HRL)
Origin airport
Lambert-St. Louis Intl.
Destination airport
Valley Intl.
Airlines serving
American Airlines, Delta, Southwest Airlines, United
Roundtrip price
$224
Distance
962 mi

St. Louis to Harlingen Flights

The cheapest times to fly from St. Louis to Harlingen

On average, Thursday can be the cheapest time to fly, according to data from the Airlines Reporting Corporation (ARC), one of the world's biggest databases for global airline sales. The data reveals that you could save up to 16% by flying on a Thursday—the cheapest day to travel on average—instead of a Sunday—the most expensive. Some of the most affordable flights from St. Louis to Harlingen are during the month of May. You can find some of the cheapest flights from St. Louis to Harlingen with Expedia's search tool and vast selection of airlines.

The best time to book a flight from St. Louis to Harlingen

Sunday is one of the best days to book for cheap flights from St. Louis to Harlingen: Tickets reserved on a Sunday cost between 6% and 13% less than those reserved on a Friday, according to ARC data. The data also suggests booking early can also lead to cheaper airfares. You could save 24% by buying your tickets for domestic flights at least a month in advance and 10% by booking international flights 2 months in advance.

How to find cheap round-trip tickets from St. Louis to Harlingen

Being flexible with your dates and using Expedia's Price Drop Protection and Price Tracking features are some of the best ways of finding a cheap ticket from St. Louis to Harlingen in 2025. You can also book with separate airlines for your outbound and return journeys, from $100 one-way. Expedia also offers Price Drop Protection, so if the cost of your airfare goes down after booking, you'll receive a credit for the difference*. This is available for a small fee, and is free to One Key Gold and Platinum tier members.

Expedia's Price Tracking feature means you can stay on top of airfares without manually checking every day. It sends you automated price alerts for cheap St. Louis to Harlingen flights and uses historical data to indicate when the best time to book is. Download Expedia's free app to activate this handy tool in a few easy taps.

You could also save big by booking one of Expedia's vacation packages. Bundling together your St. Louis to Harlingen airfare with your accommodations and car rental is often cheaper than booking everything separately. There’s also One Key, Expedia's generous rewards program. Join for free and you could earn One Key cash on most bookings to save on future adventures.

*Terms apply.

Disclaimer: ARC The statistics are based on average round-trip ticket prices between January and August 2023. The percentages you see are averages.

Frequently asked questions

Is it cheaper to buy a plane ticket from STL to Valley Intl. Airport last minute?
Being a spontaneous soul is a wonderful way to travel the world, but it isn’t always the cleverest way to land a bargain flight. Think about booking your Lambert Field to Valley Intl. Airport journey in advance instead of leaving it till the last minute. Based on flight pricing and demand studies in 2022, we have found that the best time to book domestic flights is between 28 – 35 days ahead of the departure date, and international flights three to four months in advance. You can unleash your spontaneous side when you get to your destination!
What airports do you fly into for Harlingen from St. Louis?
With Valley Intl. Airport (HRL), Brownsville-South Padre Island Intl. Airport (BRO) and Miller Intl. Airport (MFE) to select from, flying from St. Louis to Harlingen is no sweat. The city’s busiest terminal, Valley Intl. Airport (HRL), is around 3 mi northeast of the downtown area. Besides ticket prices, consider things like public transportation options from the airport and the distance to your hotel before making your choice. Get your Harlingen trip off on the right foot by exploring Iwo Jima Monument and Iwo Jima Memorial Museum.
Can I change the date of my flight from STL to Valley Intl. Airport (HRL)?
We know plans can get upended, so Expedia is here to help make amending your flight as easy as possible. To start, find your STL to Valley Intl. Airport (HRL) itinerary through the Expedia Trips portal and read the ticket rules and conditions about what changes you can make. If you booked your plane ticket in the last 24 hours, some carriers will let you cancel without charge and organize new flights. If you bought your ticket more than 24 hours ago, contact us via our Customer Service portal to find out your options.

Explore a world of travel with Expedia

*Available to One Key members.