Book flights from Harlingen/South Padre Island to Seattle/Tacoma with Southwest Airlines®. It’s easy to find the Valley International Airport to Seattle-Tacoma International Airport flight to make your booking and travel a breeze. Whether you’re traveling for business or pleasure, solo or with the whole family, you’ll enjoy flying Southwest®. Have flexible travel dates? Plug them into the Low Fare Calendar and see the lowest fares available within your travel window. You may also want to browse Southwest Vacations® to see special offers and package deals on flights, hotels, rental cars, and more.
Explore your options and book your Harlingen/South Padre Island to Seattle/Tacoma flight with Southwest today!
Best Airline in the U.S. and North America & Best Economy Class and Low Cost Airline in North America.
During the ongoing COVID-19 pandemic, the availability, health and safety procedures, operations, and schedules for local attractions are changing constantly. Please contact attractions directly for hours of operation, potential temperature screenings, and other possible health and safety procedures and restrictions. Visit our COVID-19 Travel Information page for information about potential restrictions on air travel.
Departing from: Valley International Airport (HRL)
Arriving at: Seattle-Tacoma International Airport (SEA)
Other popular flights from Harlingen/South Padre Island
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One child over 14 days and under two (2) years of age, not occupying a seat, may be carried free of charge when traveling with an adult (12 years of age or older). Learn more.
Customers flying with a pet are subject to a pet fare. To learn more about traveling with your furry friend, explore the Southwest® pet policy.
Minors under the age of 18 are not permitted to fly unaccompanied on international flights or any itinerary that includes an international flight. Learn more.
Start packing! Every ticketed Customer’s first two checked bags are free. Learn more.
At Southwest, we know it takes more than great deals on Seattle/Tacoma airfares and convenient scheduling options to make your trip memorable. So from booking to boarding, we offer services and features designed to make your travel from Harlingen/South Padre Island to Seattle/Tacoma the best it can be. Learn more about the Southwest® travel experience before you book your flight from Valley International Airport to Seattle-Tacoma International Airport.
Flying with Southwest is simple and fun, no matter which of our dozens of exciting destinations you choose. When you search for your next flight to Seattle/Tacoma, know that you won’t be surprised at checkout. Low fares and no hidden fees. That's Transfarency®. And as always, two bags fly free®1. Want the latest news, information, and promotional offers from Southwest? Sign up to receive email from us. Looking for tours, activities, and more hidden gems to add to your Seattle/Tacoma adventure? Explore getaways with Southwest®. Book your flight today and know that you'll earn Rapid Rewards® points when you fly.
1First and second checked bags. Weight and size limits apply.
2Fare difference may apply.
To find the cheapest day and time to fly Harlingen/South Padre Island to Seattle/Tacoma with Southwest, check out our Low Fare Calendar.
You can rent a car at Seattle-Tacoma International Airport—book yours with your flight.
Yes! Flights from Harlingen/South Padre Island to Seattle/Tacoma—or from here or there to anywhere—can be changed with no change fees. Fare difference may apply.
Check the status of your upcoming Southwest flight here.
Check out the Southwest Airlines® FAQs for answers about everything Southwest.
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