$165+ Cheap flights from St. Louis to Harlingen (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 12/11. Fares are subject to change and may not be available on all flights or dates of travel.
STL — HRL
Oct 25 — Nov 11
Round-trip
1 adult, Economy
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Find cheap flights from St. Louis to Harlingen with Cheapflights
1. Tell us where you want to go
Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”2. Select your favorite providers
We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.3. Compare prices and book
Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.Cheap flight deals from St. Louis to Harlingen
Cheapest
Best
Last-minute
One-way
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 September 25, 2026.
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 September 25, 2026.
This American Airlines deal was found by Cheapflights users on 9/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/235:00 am -
1 stop5h 10m
Tue 12/16:46 pm -
1 stop4h 49m
Deal found 9/23![American Airlines logo]()
$305
This American Airlines deal was found by Cheapflights users on 9/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/245:40 am -
1 stop4h 28m
Fri 10/306:42 pm -
1 stop5h 00m
Deal found 9/23![American Airlines logo]()
$307
This Southwest deal was found by Cheapflights users on 9/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/115:40 am -
1 stop6h 40m
Mon 12/147:25 am -
1 stop6h 55m
Deal found 9/24![Southwest logo]()
$327
This American Airlines deal was found by Cheapflights users on 9/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/35:00 am -
1 stop5h 14m
Sun 11/86:41 pm -
1 stop4h 52m
Deal found 9/20![American Airlines logo]()
$332
This American Airlines deal was found by Cheapflights users on 9/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/103:20 pm -
1 stop7h 30m
Sat 10/176:42 pm -
1 stop5h 00m
Deal found 9/22![American Airlines logo]()
$355
This Southwest deal was found by Cheapflights users on 9/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/236:50 pm -
1 stop4h 45m
Tue 12/17:25 am -
2 stops6h 25m
Deal found 9/24![Southwest logo]()
$379
This United Airlines deal was found by Cheapflights users on 9/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/2311:00 am -
1 stop5h 01m
Tue 12/14:39 pm -
1 stop5h 51m
Deal found 9/20![United Airlines logo]()
$382
This United Airlines deal was found by Cheapflights users on 9/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/176:15 am -
1 stop7h 06m
Wed 11/185:05 am -
1 stop4h 57m
Deal found 9/24![United Airlines logo]()
$385
Best flights from St. Louis to HarlingenDiscover 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 September 25, 2026.
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 September 25, 2026.
This American Airlines deal was found by Cheapflights users on 9/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/245:40 am -
1 stop4h 28m
Fri 10/306:42 pm -
1 stop5h 00m
Deal found 9/23![American Airlines logo]()
$307
This Southwest deal was found by Cheapflights users on 9/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/114:30 pm -
2 stops7h 00m
Mon 12/147:25 am -
2 stops6h 25m
Deal found 9/24![Southwest logo]()
$337
This United Airlines deal was found by Cheapflights users on 9/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/176:15 am -
1 stop7h 06m
Wed 11/185:05 am -
1 stop4h 57m
Deal found 9/24![United Airlines logo]()
$385
This American Airlines deal was found by Cheapflights users on 9/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/35:00 am -
1 stop5h 14m
Sun 11/86:41 pm -
1 stop4h 52m
Deal found 9/20![American Airlines logo]()
$332
This Southwest deal was found by Cheapflights users on 9/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/236:50 pm -
1 stop4h 45m
Tue 12/111:35 am -
2 stops7h 55m
Deal found 9/20![Southwest logo]()
$409
Last-minute flights from St. Louis to HarlingenDiscover last-minute flight deals from St. Louis to Harlingen. Data last updated September 25, 2026 and is based on user searches.
Discover last-minute flight deals from St. Louis to Harlingen. Data last updated September 25, 2026 and is based on user searches.
This United Airlines deal was found by Cheapflights users on 9/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/73:12 pm -
1 stop6h 40m
Sun 10/115:05 am -
1 stop5h 05m
Deal found 9/21![United Airlines logo]()
$424
This Southwest deal was found by Cheapflights users on 9/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/76:00 am -
2 stops6h 25m
Sun 10/116:25 pm -
2 stops6h 15m
Deal found 9/21![Southwest logo]()
$482
This American Airlines deal was found by Cheapflights users on 9/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/103:20 pm -
1 stop7h 30m
Sat 10/176:42 pm -
1 stop5h 00m
Deal found 9/22![American Airlines logo]()
$355
This American Airlines deal was found by Cheapflights users on 9/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/245:40 am -
1 stop4h 28m
Fri 10/306:42 pm -
1 stop5h 00m
Deal found 9/23![American Airlines logo]()
$307
This United Airlines deal was found by Cheapflights users on 9/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/246:00 am -
2 stops9h 59m
Fri 10/301:59 pm -
2 stops9h 25m
Deal found 9/25![United Airlines logo]()
$501
One-way flights from St. Louis to HarlingenSearch for one-way flight options from St. Louis to Harlingen. Find affordable one-way fares based on user searches. Data last updated September 25, 2026.
Search for one-way flight options from St. Louis to Harlingen. Find affordable one-way fares based on user searches. Data last updated September 25, 2026.
This Southwest deal was found by Cheapflights users on 9/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/116:50 pm -
1 stop4h 40m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/22![Southwest logo]()
$165
This Southwest deal was found by Cheapflights users on 9/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/205:40 am -
1 stop6h 40m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/20![Southwest logo]()
$200
Find flight deals from St. Louis to Harlingen
Discover tips and strategies to find the most affordable flight options for your journey from St. Louis (STL) to Harlingen (HRL). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated September 25, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $305 (American Airlines) |
One-way from | $165 (Southwest) |
Popular in | July |
Cheapest in | January |
Cheapflights Fare Finder
Customize your flight search to find flights from St. Louis to Harlingen that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 7,457,451 searches. Data last updated September 25, 2026.
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
Cheapest round-trip
Quickest round-trip
St. LouisHarlingen
STL Lambert-St Louis - HRL Harlingen Valley Intl
STLHRL
Lambert-St Louis
Fri 12/11
6:50 pm-11:30 pm
1 stop4h 40m
Harlingen Valley Intl
Wed 12/31
12:00 am-12:00 am
Nonstop0h 00m
$165
St. LouisHarlingen
STL Lambert-St Louis - HRL Harlingen Valley Intl
STLHRL
Lambert-St Louis
Fri 11/20
5:40 am-12:20 pm
1 stop6h 40m
Harlingen Valley Intl
Wed 12/31
12:00 am-12:00 am
Nonstop0h 00m
$200
St. LouisHarlingen
STL Lambert-St Louis - HRL Harlingen Valley Intl
STLHRL
Lambert-St Louis
Sat 10/24
5:40 am-10:08 am
1 stop4h 28m
Harlingen Valley Intl
Fri 10/30
6:42 pm-11:42 pm
1 stop5h 00m
$307
St. LouisHarlingen
STL Lambert-St Louis - HRL Harlingen Valley Intl
STLHRL
Lambert-St Louis
Tue 11/3
5:00 am-10:14 am
1 stop5h 14m
Harlingen Valley Intl
Sun 11/8
6:41 pm-11:33 pm
1 stop4h 52m
$332
St. LouisHarlingen
STL Lambert-St Louis - HRL Harlingen Valley Intl
STLHRL
Lambert-St Louis
Fri 12/11
4:30 pm-11:30 pm
2 stops7h 00m
Harlingen Valley Intl
Mon 12/14
7:25 am-1:50 pm
2 stops6h 25m
$337
St. LouisHarlingen
STL Lambert-St Louis - HRL Harlingen Valley Intl
STLHRL
Lambert-St Louis
Tue 11/17
6:15 am-1:21 pm
1 stop7h 06m
Harlingen Valley Intl
Wed 11/18
5:05 am-10:02 am
1 stop4h 57m
$385
St. LouisHarlingen
STL Lambert-St Louis - HRL Harlingen Valley Intl
STLHRL
Lambert-St Louis
Mon 11/23
6:50 pm-11:35 pm
1 stop4h 45m
Harlingen Valley Intl
Tue 12/1
11:35 am-7:30 pm
2 stops7h 55m
$409
Sorted by cheapest first
Compare providers for flights from St. Louis to Harlingen
Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from St. Louis to Harlingen in September.
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars |
- Most accurate provider: When it comes to deals on St. Louis-Harlingen flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on St. Louis-Harlingen flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from St. Louis-Harlingen flight searches over the past month and is updated monthly.
- Most trusted provider: When it comes to deals on St. Louis-Harlingen flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for St. Louis-Harlingen flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.
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.
STL-HRL
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.
Reviews of airlines servicing Harlingen
Get insights into the airlines that provide service to Harlingen. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Harlingen. Reviews last updated September 25, 2026.
Get a feel of what it's like to fly with Southwest 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.
Overall
8.0
Crew
8.6
Food
7.0
Comfort
8.0
Boarding
8.1
Entertainment
7.5
Reviews
1 / 20
2.0
MediocreMike,Aug 2025
OKC - AUS
Overall
8.0
Crew
8.6
Food
7.0
Comfort
8.0
Boarding
8.1
Entertainment
7.5
Reviews
1 / 20
2.0
MediocreMike,Aug 2025
OKC - AUS
Overall
8.0
Crew
8.6
Food
7.0
Comfort
8.0
Boarding
8.1
Entertainment
7.5
Reviews
1 / 20
2.0
MediocreMike,Aug 2025
OKC - AUS
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.
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Complete your trip
Complete your trip to Harlingen by adding a car rental and/or hotel reservation to your travel itinerary.
Search flights from St. Louis to Harlingen by cabin class
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Other flights to Harlingen
Explore flights to Harlingen departing from other origins. Flights are based on user searches made on Cheapflights and were last updated on September 25, 2026.
St. Louis and Harlingen flights
Browse other St. Louis and Harlingen flight options. Last updated on September 25, 2026.
Other flights from St. Louis
Browse through other flights departing from St. Louis. Flights are based on user searches made on Cheapflights and were last updated on September 25, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
Top 2 airlines flying from St. Louis to Harlingen
Discover the top 2 airlines that operate flights from St. Louis to Harlingen. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 7,457,451 searches. Data last updated September 25, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$212 | Average$390 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$244 | Average$417 | FlexibilityNo cancel fee | On-time63% |