What are the cheapest airlines flying from St. Louis to Harlingen, Texas round-trip?

Southwest, at $196, was found to be the cheapest airline from St. Louis to Harlingen, Texas.Alternate airlines to your destination round-trip include American Airlines and Delta. Southwest is 39% cheaper than the average price of flights available within the next 90 days to this destination.

What is the cheapest day to fly from St. Louis to Harlingen, Texas?

Travelers seeking maximum savings on their St. Louis to Harlingen, Texas flight should consider departing on Monday mornings when fares are most often at their lowest. Friday afternoons flights should be avoided if possible as fares are typically the most expensive at this time.

In terms of precipitation, rainfall in Harlingen, Texas ranges from 1.1 - 5.2 inches per month. September is typically the wettest month, when rainfall can reach 5.2 in. January is typically the driest time to visit Harlingen, Texas when rainfall is around 1.1 in.

If weather is an important factor for your trip to Harlingen, Texas, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 84.2 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 60.8 F).

What are the most popular airlines that fly from St. Louis to Harlingen, Texas?

When booking a flight from St. Louis to Harlingen, Texas, you may want to consider flying on American Airlines, Delta or Southwest as they are the most popular for this route.

What is the cheapest day to fly round-trip from St. Louis to Harlingen, Texas?

Departing on a Sunday is a good option for securing a great price. You can expect to save up to 45% when planning your travel around this day of the week.

What is the cheapest month to fly from St. Louis to Harlingen, Texas?

Flights from St. Louis to Harlingen, Texas lean towards being more expensive in March. Prices are generally better when you fly from St. Louis to Harlingen, Texas in May, with the cheapest ticket starting at $196.

Can I find deals for flights from St. Louis to Harlingen that include hotel bookings?

Yes. In addition to deals on St. Louis to Harlingen flights, Cheapflights offers vacation packages that include both flights and hotel.

How can I find direct flights from St. Louis to Harlingen?

After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from St. Louis to Harlingen.

Can I find deals for business class flights from St. Louis to Harlingen?

Yes. Cheapflights offers flight deals from St. Louis to Harlingen by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

$243+ Cheap Flights from St. Louis to Harlingen, TX

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Cheap flight deals from St. Louis to Harlingen

Round-trip from	$243 (Southwest)
Popular in	March
Cheapest in	May
Average price	$217

From Lambert-St Louis to Harlingen Valley Intl

Search Deals

Highest demand for flights based on searches. 15% potential increase in price ($60 potential increase over avg. RT price).

Search Deals

Cheapest flight prices on average. 8% potential price decrease ($27 potential savings vs. average RT price).

Search Deals

Average for round-trip flights in August 2025

Search Deals

Find flight deals from St. Louis to Harlingen

Cheapest flights from St. Louis to Harlingen
Explore the most affordable flight options available from St. Louis to Harlingen. Find the lowest fares from popular airlines and budget airlines, with prices last updated on agosto 14, 2025.

dom. 9/145:35 amSTL - HRL

1 stop4h 05mSouthwest

dom. 9/144:00 pmHRL - STL

1 stop6h 40mSouthwest

Deal found 8/12

$243

mié. 8/274:32 pmSTL - HRL

1 stop5h 20mUnited Airlines

dom. 8/315:20 pmHRL - STL

1 stop4h 48mUnited Airlines

Deal found 8/12

$339

jue. 8/285:15 amSTL - HRL

1 stop4h 17mAmerican Airlines

lun. 9/15:30 amHRL - STL

1 stop6h 20mAmerican Airlines

Deal found 8/13

$369

mar. 12/234:17 pmSTL - HRL

1 stop27h 19mUnited Airlines

dom. 12/285:00 amHRL - STL

1 stop4h 49mUnited Airlines

Deal found 8/14

$440

jue. 8/2811:30 amSTL - HRL

2 stops10h 22mUnited Airlines

lun. 9/15:00 amHRL - STL

1 stop5h 01mUnited Airlines

Deal found 8/13

$481

Best flights from St. Louis to Harlingen
Discover carefully curated flight deals from St. Louis to Harlingen that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated agosto 14, 2025.

dom. 9/145:35 amSTL - HRL

1 stop4h 05mSouthwest

dom. 9/144:00 pmHRL - STL

1 stop6h 40mSouthwest

Deal found 8/12

$243

mié. 8/274:32 pmSTL - HRL

1 stop5h 20mUnited Airlines

dom. 8/315:20 pmHRL - STL

1 stop4h 48mUnited Airlines

Deal found 8/12

$339

jue. 8/285:15 amSTL - HRL

1 stop4h 17mAmerican Airlines

lun. 9/15:30 amHRL - STL

1 stop6h 20mAmerican Airlines

Deal found 8/13

$369

mar. 12/234:17 pmSTL - HRL

1 stop27h 19mUnited Airlines

dom. 12/285:00 amHRL - STL

1 stop4h 49mUnited Airlines

Deal found 8/12

$440

Last-minute flights from St. Louis to Harlingen
Discover last-minute flight deals from St. Louis to Harlingen. Data last updated agosto 14, 2025 and is based on user searches.

mié. 8/274:32 pmSTL - HRL

1 stop5h 20mUnited Airlines

dom. 8/315:20 pmHRL - STL

1 stop4h 48mUnited Airlines

Deal found 8/12

$339

jue. 8/285:15 amSTL - HRL

1 stop4h 17mAmerican Airlines

lun. 9/15:30 amHRL - STL

1 stop6h 20mAmerican Airlines

Deal found 8/13

$369

jue. 8/2811:30 amSTL - HRL

2 stops10h 22mUnited Airlines

lun. 9/15:00 amHRL - STL

1 stop5h 01mUnited Airlines

Deal found 8/13

$481

dom. 9/145:35 amSTL - HRL

1 stop4h 05mSouthwest

dom. 9/144:00 pmHRL - STL

1 stop6h 40mSouthwest

Deal found 8/12

$243

Cheapflights Fare Finder

Use the filters below to find and compare flights from St. Louis to Harlingen that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

St. LouisHarlingen

STL - HRL

STLHRL

Lambert-St Louis

dom. 9/14

5:35 am-9:40 am

1 stop4h 05m

Harlingen Valley Intl

dom. 9/14

4:00 pm-10:40 pm

1 stop6h 40m

$243

St. LouisHarlingen

STL - HRL

STLHRL

Lambert-St Louis

mié. 8/27

4:32 pm-9:52 pm

1 stop5h 20m

Harlingen Valley Intl

dom. 8/31

5:20 pm-10:08 pm

1 stop4h 48m

$339

St. LouisHarlingen

STL - HRL

STLHRL

Lambert-St Louis

jue. 8/28

5:15 am-9:32 am

1 stop4h 17m

Harlingen Valley Intl

lun. 9/1

5:30 am-11:50 am

1 stop6h 20m

$369

St. LouisHarlingen

STL - HRL

STLHRL

Lambert-St Louis

mar. 12/23

4:17 pm-7:36 pm

1 stop27h 19m

Harlingen Valley Intl

dom. 12/28

5:00 am-9:49 am

1 stop4h 49m

$440

Flights are sorted by cheapest round-trip flights first.

Deals found on 8/12

Best time to book a flight from St. Louis to Harlingen

Have a flexible travel schedule? Discover the best time to fly to Harlingen from St. Louis with our price prediction graph.

Estimated round-trip price

Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from St. Louis to Harlingen

What is the cheapest month to book a flight from St. Louis to Harlingen, Texas?

Currently, April is the cheapest month in which you can book a flight from St. Louis to Harlingen, Texas (average of $267). Flying from St. Louis to Harlingen, Texas in June is currently the most expensive (average of $381). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest time of day to fly from STL to HRL?

Unlike in the morning, when flights are generally more expensive, you can save up to 6% on flights from St. Louis to Harlingen, Texas by exploring options for tickets at noon.

Reviews of airlines servicing Harlingen

Get a feel of what it's like to fly with Southwest, Delta, and American Airlines from St. Louis to Harlingen by reading reviews from past customers. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.

Southwest

8.0

Very good

4,244 reviews

Reviews

1 / 20

8.0

Excellent

Ila,Mar 2025

HOU - DAL

Our original flight was delayed. We were able to change our flight and got home at close to the same time. Looking forward to when you have assigned seating.

Southwest

8.0

Very good

4,244 reviews

Southwest

8.0

Very good

4,244 reviews

Reviews

1 / 20

8.0

Excellent

Ila,Mar 2025

HOU - DAL

Our original flight was delayed. We were able to change our flight and got home at close to the same time. Looking forward to when you have assigned seating.

Delta

8.0

Very good

7,980 reviews

Southwest

8.0

Very good

4,244 reviews

Reviews

1 / 20

8.0

Excellent

Ila,Mar 2025

HOU - DAL

Our original flight was delayed. We were able to change our flight and got home at close to the same time. Looking forward to when you have assigned seating.

American Airlines

7.2

Good

10,000 reviews

Southwest

8.0

Very good

4,244 reviews

Reviews

1 / 20

8.0

Excellent

Ila,Mar 2025

HOU - DAL

Our original flight was delayed. We were able to change our flight and got home at close to the same time. Looking forward to when you have assigned seating.

Related info for your journey

What are the cheapest airlines flying from St. Louis to Harlingen, Texas round-trip?
Southwest, at $196, was found to be the cheapest airline from St. Louis to Harlingen, Texas.Alternate airlines to your destination round-trip include American Airlines and Delta. Southwest is 39% cheaper than the average price of flights available within the next 90 days to this destination.
Can I find deals for flights from St. Louis to Harlingen that include hotel bookings?
Yes. In addition to deals on St. Louis to Harlingen flights, Cheapflights offers vacation packages that include both flights and hotel.
How can I find direct flights from St. Louis to Harlingen?
After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from St. Louis to Harlingen.
Can I find deals for business class flights from St. Louis to Harlingen?
Yes. Cheapflights offers flight deals from St. Louis to Harlingen by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.
What is the cheapest month to book a flight from St. Louis to Harlingen, Texas?
Currently, April is the cheapest month in which you can book a flight from St. Louis to Harlingen, Texas (average of $267). Flying from St. Louis to Harlingen, Texas in June is currently the most expensive (average of $381). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

Browse thousands of different options on Cheapflights for your next trip

Top 3 airlines flying from St. Louis to Harlingen

Airline	Cheapest	Average	Flexibility	On-time
Southwest	Cheapest$196	Average$313	FlexibilityNo cancel fee	On-time63%
American Airlines	Cheapest$208	Average$328	FlexibilityNo cancel fee	On-time71%
Delta	Cheapest$353	Average$421	FlexibilityNo cancel fee	On-timeN/A

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$243+ Cheap flights from St. Louis to Harlingen, TX (STL - HRL)

This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 9/14. Fares are subject to change and may not be available on all flights or dates of travel.

Find cheap flights from St. Louis to Harlingen with Cheapflights

1. Tell us where you want to go

2. Select your favorite providers

3. Compare prices and book

Cheap flight deals from St. Louis to Harlingen

Round-trip from

Popular in

Cheapest in

Average price

Find flight deals from St. Louis to Harlingen

Cheapest flights from St. Louis to HarlingenExplore the most affordable flight options available from St. Louis to Harlingen. Find the lowest fares from popular airlines and budget airlines, with prices last updated on agosto 14, 2025.

Explore the most affordable flight options available from St. Louis to Harlingen. Find the lowest fares from popular airlines and budget airlines, with prices last updated on agosto 14, 2025.

Cheapflights Fare Finder

Use the filters below to find and compare flights from St. Louis to Harlingen that are best for you.

Best time to book a flight from St. Louis to Harlingen

Have a flexible travel schedule? Discover the best time to fly to Harlingen from St. Louis with our price prediction graph.

Cheapflights Insights

Everything you need to know about your flight from St. Louis to Harlingen

What is the cheapest month to book a flight from St. Louis to Harlingen, Texas?

What is the cheapest time of day to fly from STL to HRL?

Find hourly flight availability from St. Louis to Harlingen. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated agosto 14, 2025.

Reviews of airlines servicing Harlingen

Get a feel of what it's like to fly with Southwest, Delta, and American Airlines from St. Louis to Harlingen by reading reviews from past customers. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.

Related info for your journey

Find useful and relevant information for your journey from St. Louis to Harlingen. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

What are the cheapest airlines flying from St. Louis to Harlingen, Texas round-trip?

Can I find deals for flights from St. Louis to Harlingen that include hotel bookings?

How can I find direct flights from St. Louis to Harlingen?

Can I find deals for business class flights from St. Louis to Harlingen?

What is the cheapest month to book a flight from St. Louis to Harlingen, Texas?

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Alternative routes for St. Louis to Harlingen

See prices for flight routes from nearby airports that may be better suited for you.

Top 3 airlines flying from St. Louis to Harlingen

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Book with Flexibility

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Cheapest flights from St. Louis to Harlingen
Explore the most affordable flight options available from St. Louis to Harlingen. Find the lowest fares from popular airlines and budget airlines, with prices last updated on agosto 14, 2025.