$129+ Cheap flights from St. Louis to Harlingen, TX (STL - HRL)
This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 4/29. Fares are subject to change and may not be available on all flights or dates of travel.
STL — HRL
Apr 23 — Apr 301
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 March 24, 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 March 24, 2026.
This United Airlines deal was found by Cheapflights users on 3/19. 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 4/156:00 am
STL
- HRL
1 stop5h 23m
United Airlines
Thu 4/235:18 pm
HRL
- STL
1 stop5h 10m
United Airlines
Deal found 3/19![United Airlines logo]()
$255
This Southwest deal was found by Cheapflights users on 3/21. 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.
Thu 6/47:20 pm
STL
- HRL
1 stop4h 20m
Southwest
Tue 6/95:00 pm
HRL
- STL
1 stop4h 10m
Southwest
Deal found 3/21![Southwest logo]()
$257
This Southwest deal was found by Cheapflights users on 3/24. 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.
Tue 6/98:30 am
STL
- HRL
1 stop5h 00m
Southwest
Sat 6/135:10 pm
HRL
- STL
1 stop6h 20m
Southwest
Deal found 3/24![Southwest logo]()
$261
This Southwest deal was found by Cheapflights users on 3/21. 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.
Fri 6/57:20 pm
STL
- HRL
1 stop4h 20m
Southwest
Wed 6/102:10 pm
HRL
- STL
2 stops7h 00m
Southwest
Deal found 3/21![Southwest logo]()
$262
This United Airlines deal was found by Cheapflights users on 3/23. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/79:10 am
STL
- HRL
2 stops12h 49m
United Airlines
Sat 4/115:18 pm
HRL
- STL
1 stop5h 10m
United Airlines
Deal found 3/23![United Airlines logo]()
$270
This Southwest deal was found by Cheapflights users on 3/19. 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 4/66:40 pm
STL
- HRL
1 stop5h 25m
Southwest
Wed 4/84:40 pm
HRL
- STL
1 stop5h 40m
Southwest
Deal found 3/19![Southwest logo]()
$300
This United Airlines deal was found by Cheapflights users on 3/20. 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.
Sat 4/114:49 pm
STL
- HRL
1 stop5h 10m
United Airlines
Wed 4/155:18 pm
HRL
- STL
1 stop5h 10m
United Airlines
Deal found 3/20![United Airlines logo]()
$308
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 March 24, 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 March 24, 2026.
This United Airlines deal was found by Cheapflights users on 3/19. 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 4/156:00 am
STL
- HRL
1 stop5h 23m
United Airlines
Thu 4/235:18 pm
HRL
- STL
1 stop5h 10m
United Airlines
Deal found 3/19![United Airlines logo]()
$255
This Southwest deal was found by Cheapflights users on 3/21. 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.
Thu 6/47:20 pm
STL
- HRL
1 stop4h 20m
Southwest
Tue 6/95:00 pm
HRL
- STL
1 stop4h 10m
Southwest
Deal found 3/21![Southwest logo]()
$257
This American Airlines deal was found by Cheapflights users on 3/22. 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.
Mon 4/65:12 am
STL
- HRL
1 stop5h 00m
American Airlines
Wed 4/810:47 am
HRL
- STL
1 stop6h 34m
American Airlines
Deal found 3/22![American Airlines logo]()
$335
This Southwest deal was found by Cheapflights users on 3/24. 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.
Tue 6/98:30 am
STL
- HRL
1 stop5h 00m
Southwest
Sat 6/135:10 pm
HRL
- STL
1 stop6h 20m
Southwest
Deal found 3/24![Southwest logo]()
$261
This Southwest deal was found by Cheapflights users on 3/21. 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.
Fri 6/52:55 pm
STL
- HRL
2 stops6h 45m
Southwest
Tue 6/95:00 pm
HRL
- STL
1 stop4h 10m
Southwest
Deal found 3/21![Southwest logo]()
$262
This United Airlines deal was found by Cheapflights users on 3/20. 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.
Sat 4/119:16 am
STL
- HRL
2 stops12h 43m
United Airlines
Wed 4/155:18 pm
HRL
- STL
1 stop5h 10m
United Airlines
Deal found 3/20![United Airlines logo]()
$313
This Southwest deal was found by Cheapflights users on 3/21. 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.
Fri 6/55:25 pm
STL
- HRL
2 stops6h 15m
Southwest
Wed 6/102:10 pm
HRL
- STL
2 stops7h 00m
Southwest
Deal found 3/21![Southwest logo]()
$267
Last-minute flights from St. Louis to HarlingenDiscover last-minute flight deals from St. Louis to Harlingen. Data last updated March 24, 2026 and is based on user searches.
Discover last-minute flight deals from St. Louis to Harlingen. Data last updated March 24, 2026 and is based on user searches.
This United Airlines deal was found by Cheapflights users on 3/24. 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.
Sat 3/284:47 pm
STL
- HRL
1 stop5h 09m
United Airlines
Mon 3/305:18 pm
HRL
- STL
1 stop5h 10m
United Airlines
Deal found 3/24![United Airlines logo]()
$337
This Southwest deal was found by Cheapflights users on 3/24. 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.
Sat 3/285:25 pm
STL
- HRL
2 stops6h 30m
Southwest
Mon 3/306:25 pm
HRL
- STL
1 stop5h 40m
Southwest
Deal found 3/24![Southwest logo]()
$342
This American Airlines deal was found by Cheapflights users on 3/19. 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 3/305:12 am
STL
- HRL
1 stop5h 00m
American Airlines
Thu 4/26:00 am
HRL
- STL
1 stop4h 59m
American Airlines
Deal found 3/19![American Airlines logo]()
$323
This Southwest deal was found by Cheapflights users on 3/19. 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 4/66:40 pm
STL
- HRL
1 stop5h 25m
Southwest
Wed 4/84:40 pm
HRL
- STL
1 stop5h 40m
Southwest
Deal found 3/19![Southwest logo]()
$300
This American Airlines deal was found by Cheapflights users on 3/22. 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.
Mon 4/65:12 am
STL
- HRL
1 stop5h 00m
American Airlines
Wed 4/810:47 am
HRL
- STL
1 stop6h 34m
American Airlines
Deal found 3/22![American Airlines logo]()
$335
This United Airlines deal was found by Cheapflights users on 3/23. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/79:10 am
STL
- HRL
2 stops12h 49m
United Airlines
Sat 4/115:18 pm
HRL
- STL
1 stop5h 10m
United Airlines
Deal found 3/23![United Airlines logo]()
$270
This American Airlines deal was found by Cheapflights users on 3/23. 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.
Tue 4/75:20 am
STL
- HRL
1 stop4h 57m
American Airlines
Sat 4/112:47 pm
HRL
- STL
1 stop4h 43m
American Airlines
Deal found 3/23![American Airlines logo]()
$329
This United Airlines deal was found by Cheapflights users on 3/20. 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.
Sat 4/114:49 pm
STL
- HRL
1 stop5h 10m
United Airlines
Wed 4/155:18 pm
HRL
- STL
1 stop5h 10m
United Airlines
Deal found 3/20![United Airlines logo]()
$308
This United Airlines deal was found by Cheapflights users on 3/19. 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 4/156:00 am
STL
- HRL
1 stop5h 23m
United Airlines
Thu 4/235:18 pm
HRL
- STL
1 stop5h 10m
United Airlines
Deal found 3/19![United Airlines logo]()
$255
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 March 24, 2026.
Search for one-way flight options from St. Louis to Harlingen. Find affordable one-way fares based on user searches. Data last updated March 24, 2026.
This United Airlines deal was found by Cheapflights users on 3/22. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/296:00 am
STL
- HRL
1 stop5h 23m
United Airlines
Deal found 3/22![United Airlines logo]()
$129
This Southwest deal was found by Cheapflights users on 3/22. 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.
Wed 4/292:30 pm
STL
- HRL
2 stops7h 30m
Southwest
Deal found 3/22![Southwest logo]()
$134
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 March 24, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $255 (United Airlines) |
One-way from | $129 (United Airlines) |
Popular in | December |
Cheapest in | May |
Average price | $420 |
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 2,558,603 searches. Data last updated March 24, 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
St. LouisHarlingen
STL - HRL
STLHRL
Lambert-St Louis
Wed 4/15
6:00 am-11:23 am
1 stop5h 23m
Harlingen Valley Intl
Thu 4/23
5:18 pm-10:28 pm
1 stop5h 10m
$255
Quickest round-trip
St. LouisHarlingen
STL - HRL
STLHRL
Lambert-St Louis
Thu 6/4
7:20 pm-11:40 pm
1 stop4h 20m
Harlingen Valley Intl
Tue 6/9
5:00 pm-9:10 pm
1 stop4h 10m
$257
St. LouisHarlingen
STL - HRL
STLHRL
Lambert-St Louis
Tue 6/9
8:30 am-1:30 pm
1 stop5h 00m
Harlingen Valley Intl
Sat 6/13
5:10 pm-11:30 pm
1 stop6h 20m
$261
St. LouisHarlingen
STL - HRL
STLHRL
Lambert-St Louis
Fri 6/5
2:55 pm-9:40 pm
2 stops6h 45m
Harlingen Valley Intl
Tue 6/9
5:00 pm-9:10 pm
1 stop4h 10m
$262
St. LouisHarlingen
STL - HRL
STLHRL
Lambert-St Louis
Fri 6/5
5:25 pm-11:40 pm
2 stops6h 15m
Harlingen Valley Intl
Wed 6/10
2:10 pm-9:10 pm
2 stops7h 00m
$267
St. LouisHarlingen
STL - HRL
STLHRL
Lambert-St Louis
Sat 4/11
9:16 am-9:59 pm
2 stops12h 43m
Harlingen Valley Intl
Wed 4/15
5:18 pm-10:28 pm
1 stop5h 10m
$313
St. LouisHarlingen
STL - HRL
STLHRL
Lambert-St Louis
Mon 4/6
5:12 am-10:12 am
1 stop5h 00m
Harlingen Valley Intl
Wed 4/8
10:47 am-5:21 pm
1 stop6h 34m
$335
Cheapest one-way
Quickest one-way
St. LouisHarlingen
STL - HRL
STLHRL
Lambert-St Louis
Wed 4/29
6:00 am-11:23 am
1 stop5h 23m
$129
St. LouisHarlingen
STL - HRL
STLHRL
Lambert-St Louis
Wed 4/29
2:30 pm-10:00 pm
2 stops7h 30m
$134
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 March.
| 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, Texas 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, Texas flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from St. Louis-Harlingen, Texas flight searches over the past month and is updated monthly.
- Most trusted provider: When it comes to deals on St. Louis-Harlingen, Texas 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, Texas 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.
Cheapflights Insights
Everything you need to know about your flight from St. Louis to Harlingen
Prices
More
What’s the top layover airport for flights from St. Louis to Harlingen, Texas?
Share of 1-stop round-trip flights from St. Louis to Harlingen, Texas chosen by Cheapflights users in the past 12 months, using the same layover each way.
Houston (IAH) – chosen by Cheapflights users on 50% of 1-stop itineraries from St. Louis to Harlingen, Texas on Cheapflights.
What’s the cheapest layover airport for flights from St. Louis to Harlingen, Texas?
Average round-trip fare for 1-stop flights from St. Louis to Harlingen, Texas, chosen by Cheapflights users in the past 12 months, with the same layover each way.
Houston (HOU) is the most affordable 1-stop option, with an average round-trip price of $217.
What’s the fastest layover option from St. Louis to Harlingen, Texas?
Shortest average travel time for 1-stop one-way flights from St. Louis to Harlingen, Texas, based on itineraries clicked by Cheapflights users over the past 12 months, grouped by layover airport.
Flights via Houston (HOU) have the shortest average one-way travel time for 1-stop routes: 4h 55m.
Which airport typically offers the quickest layover for flights from St. Louis to Harlingen, Texas?
Average layover duration for 1-stop one-way flights from St. Louis to Harlingen, Texas, chosen by Cheapflights users in the last 12 months, grouped by stopover airport.
Flights via Houston (IAH) offer the fastest connection on this route, with an average layover time of 1h 17m.
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 March 24, 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.
Food
7.0
Boarding
8.1
Comfort
8.0
Entertainment
7.5
Crew
8.6
Overall
8.0
Reviews
1 / 20
2.0
MediocreMike,Aug 2025
OKC - AUS
Food
7.0
Boarding
8.1
Comfort
8.0
Entertainment
7.5
Crew
8.6
Overall
8.0
Reviews
1 / 20
2.0
MediocreMike,Aug 2025
OKC - AUS
Food
7.0
Boarding
8.1
Comfort
8.0
Entertainment
7.5
Crew
8.6
Overall
8.0
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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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 March 24, 2026.
St. Louis and Harlingen flights
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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 2,558,603 searches. Data last updated March 24, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$212 | Average$390 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$216 | Average$362 | FlexibilityNo cancel fee | On-time63% |