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$338+ Cheap flights from Harlingen to Seattle (HRL - SEA)

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 9/1. Fares are subject to change and may not be available on all flights or dates of travel.
HRL — SEA
Aug 29 — Sep 51
Sat 8/29
Sat 9/5
1 adult, Economy
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Cheap flight deals from Harlingen to Seattle

Cheapest flights from Harlingen to Seattle
Explore the most affordable flight options available from Harlingen to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on July 30, 2026.

This American Airlines deal was found by Cheapflights users on 7/29. 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.
Fri 9/183:35 pm
HRL
-
SEA
1 stop8h 17m
American Airlines
Sat 9/265:30 am
SEA
-
HRL
1 stop7h 35m
American Airlines
Deal found 7/29$338
This Southwest deal was found by Cheapflights users on 7/29. 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 9/13:25 pm
HRL
-
SEA
2 stops9h 40m
Southwest
Thu 9/312:35 pm
SEA
-
HRL
1 stop6h 00m
Southwest
Deal found 7/29$343
This American Airlines deal was found by Cheapflights users on 7/25. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/278:03 pm
HRL
-
SEA
1 stop6h 47m
American Airlines
Thu 9/35:00 am
SEA
-
HRL
1 stop9h 27m
American Airlines
Deal found 7/25$359
This Southwest deal was found by Cheapflights users on 7/28. 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 9/185:55 pm
HRL
-
SEA
2 stops8h 50m
Southwest
Sat 9/265:30 am
SEA
-
HRL
2 stops11h 25m
Southwest
Deal found 7/28$369
This Southwest deal was found by Cheapflights users on 7/25. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/275:55 pm
HRL
-
SEA
2 stops8h 45m
Southwest
Thu 9/312:35 pm
SEA
-
HRL
1 stop6h 00m
Southwest
Deal found 7/25$374
This Southwest deal was found by Cheapflights users on 7/27. 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.
Sun 12/65:50 pm
HRL
-
SEA
2 stops9h 05m
Southwest
Tue 12/89:20 am
SEA
-
HRL
1 stop9h 15m
Southwest
Deal found 7/27$377
This Southwest deal was found by Cheapflights users on 7/29. 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 9/185:55 pm
HRL
-
SEA
2 stops8h 50m
Southwest
Sun 9/279:25 pm
SEA
-
HRL
2 stops11h 55m
Southwest
Deal found 7/29$395

Find flight deals from Harlingen to Seattle

Discover tips and strategies to find the most affordable flight options for your journey from Harlingen (HRL) to Seattle (SEA). 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 July 30, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$338
(American Airlines)

Popular in

January

Cheapest in

February

Average price

$457
Provider with most accurate pricing for Harlingen Valley Intl-Seattle/Tacoma Intl flight deals.
Search Deals
Provider most trusted by Cheapflights users for Harlingen Valley Intl-Seattle/Tacoma Intl flights.
Search Deals
From Harlingen Valley Intl to Seattle/Tacoma Intl
Search Deals
Highest demand for flights based on searches. 3% potential increase in price ($16 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease ($16 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in July 2026
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Harlingen to Seattle 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 July 30, 2026.
Use the filters below to find and compare flights from Harlingen to Seattle that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip
Quickest round-trip

HarlingenSeattle

HRL - SEA

HRLSEA

Harlingen Valley Intl

Tue 9/1

1:45 pm-6:35 pm

1 stop6h 50m

Seattle/Tacoma Intl

Thu 9/3

12:35 pm-8:35 pm

1 stop6h 00m

$338

HarlingenSeattle

HRL - SEA

HRLSEA

Harlingen Valley Intl

Thu 8/27

8:03 pm-12:50 am

1 stop6h 47m

Seattle/Tacoma Intl

Thu 9/3

5:00 am-4:27 pm

1 stop9h 27m

$359

HarlingenSeattle

HRL - SEA

HRLSEA

Harlingen Valley Intl

Thu 8/27

5:55 pm-12:40 am

2 stops8h 45m

Seattle/Tacoma Intl

Thu 9/3

12:35 pm-8:35 pm

1 stop6h 00m

$374

HarlingenSeattle

HRL - SEA

HRLSEA

Harlingen Valley Intl

Sun 12/6

4:45 pm-12:55 am

2 stops10h 10m

Seattle/Tacoma Intl

Tue 12/8

5:45 am-5:15 pm

2 stops9h 30m

$376

HarlingenSeattle

HRL - SEA

HRLSEA

Harlingen Valley Intl

Sat 10/24

7:15 am-12:48 pm

1 stop7h 33m

Seattle/Tacoma Intl

Wed 10/28

7:05 am-4:01 pm

1 stop6h 56m

$417

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/29

Sorted by cheapest first

Compare providers for flights from Harlingen to Seattle

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 Harlingen to Seattle in July.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on Harlingen-Seattle flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Harlingen-Seattle flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Harlingen-Seattle flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Harlingen-Seattle 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 Harlingen-Seattle 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 Harlingen to Seattle

Have a flexible travel schedule? Discover the best time to fly to Seattle from Harlingen 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 Harlingen to Seattle

What is the cheapest month to book a flight from Harlingen to Seattle?

Currently, February is the cheapest month in which you can book a flight from Harlingen to Seattle (average of $263). Flying from Harlingen to Seattle in January is currently the most expensive (average of $604). 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.

Reviews of airlines servicing Seattle

Get insights into the airlines that provide service to Seattle. 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 Seattle. Reviews last updated July 30, 2026.
Read through reviews of airlines operating flights from Harlingen to Seattle, such as Southwest,United Airlines, andAmerican Airlines. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.0
Very good
4,229 reviews

Comfort

8.0

Food

7.0

Overall

8.0

Entertainment

7.5

Crew

8.6

Boarding

8.1

Reviews

1 / 20
6.0
Good

Scott,Feb 2026

HOU - FLL

Delayed by 45 minutes leaving Houston, making a 3.5 hour layover that much longer.
Southwest
8.0
Very good
4,229 reviews
Southwest
8.0
Very good
4,229 reviews

Comfort

8.0

Food

7.0

Overall

8.0

Entertainment

7.5

Crew

8.6

Boarding

8.1

Reviews

1 / 20
6.0
Good

Scott,Feb 2026

HOU - FLL

Delayed by 45 minutes leaving Houston, making a 3.5 hour layover that much longer.
United Airlines
7.4
Good
10,052 reviews
Southwest
8.0
Very good
4,229 reviews

Comfort

8.0

Food

7.0

Overall

8.0

Entertainment

7.5

Crew

8.6

Boarding

8.1

Reviews

1 / 20
6.0
Good

Scott,Feb 2026

HOU - FLL

Delayed by 45 minutes leaving Houston, making a 3.5 hour layover that much longer.
American Airlines
7.1
Good
11,848 reviews
Southwest
8.0
Very good
4,229 reviews

Comfort

8.0

Food

7.0

Overall

8.0

Entertainment

7.5

Crew

8.6

Boarding

8.1

Reviews

1 / 20
6.0
Good

Scott,Feb 2026

HOU - FLL

Delayed by 45 minutes leaving Houston, making a 3.5 hour layover that much longer.

Related info for your journey

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

  • How long is the flight from Harlingen to Seattle?

    Southwest and American Airlines can get you from Harlingen to Seattle in just under 6h 47m. Your travel time can differ by up to 03m. There are 1984 mi between Harlingen and Seattle. Both multi-stop and nonstop flights can be found to your destination and back.

  • What are the cheapest airlines flying from Harlingen to Seattle round-trip?

    Flying on American Airlines is currently your cheapest option to Seattle, with prices starting at $215. Additional round-trip tickets that might be worth considering are offered by United Airlines and Southwest, with the lowest prices starting at $236 and $297, respectively. American Airlines is currently priced 49% below the average price you’ll pay for this route.

  • Can I find deals for flights from Harlingen to Seattle that include hotel bookings?

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

  • How can I find direct flights from Harlingen to Seattle?

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

  • Can I find deals for business class flights from Harlingen to Seattle?

    Yes. Cheapflights offers flight deals from Harlingen to Seattle 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 Harlingen to Seattle?

    Currently, February is the cheapest month in which you can book a flight from Harlingen to Seattle (average of $263). Flying from Harlingen to Seattle in January is currently the most expensive (average of $604). 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

Traveling to a place near Seattle?

Book flights to Seattle if you plan to visit one of these locations
SeaTac
Renton
Tacoma
Lacey
Leavenworth
Olympia
Edmonds
Tukwila
Snoqualmie
Tumwater
Centralia
Puyallup
Kent
Ellensburg
Fife
Marysville
Ocean Shores
Lakewood
Lynnwood
Shoreline

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Top 3 airlines flying from Harlingen to Seattle

Discover the top 3 airlines that operate flights from Harlingen to Seattle. 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 July 30, 2026.
AirlineCheapestAverageFlexibilityOn-time
American AirlinesCheapest$215Average$426FlexibilityNo cancel feeOn-time71%
United AirlinesCheapest$236Average$397FlexibilityNo cancel feeOn-time69%
SouthwestCheapest$297Average$423FlexibilityNo cancel feeOn-time63%

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