₩134,100 Cheap Flights from St. Louis (STL) to Seattle (SEA)

View ₩134,100 flight on Fri, Jun 20, 2025Opens in a new window

Popular airlines from St. Louis Lambert Intl. Airport (STL) to Seattle-Tacoma International Airport (SEA)

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Cheap Flights from St. Louis to Seattle (STL-SEA)

Prices were available within the past 7 days and start at ₩134,100 for one-way flights and ₩366,400 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

American Airlines
Sat, Jun 14 - Fri, Jun 20
STL
St. Louis
SEA
Seattle
₩366,400 Roundtrip, found 2 days ago
₩366,400
Roundtrip
found 2 days ago
Select American Airlines flight, departing Sat, Jun 14 from St. Louis to Seattle, returning Fri, Jun 20, priced at ₩366,400 found 2 days ago
United
Sat, May 3 - Mon, May 12
STL
St. Louis
SEA
Seattle
₩382,800 Roundtrip, found 5 days ago
₩382,800
Roundtrip
found 5 days ago
Select United flight, departing Sat, May 3 from St. Louis to Seattle, returning Mon, May 12, priced at ₩382,800 found 5 days ago
Delta
Wed, Aug 20 - Sat, Aug 23
STL
St. Louis
SEA
Seattle
₩387,100 Roundtrip, found 6 days ago
₩387,100
Roundtrip
found 6 days ago
Select Delta flight, departing Wed, Aug 20 from St. Louis to Seattle, returning Sat, Aug 23, priced at ₩387,100 found 6 days ago
Delta
Sat, Jun 14 - Fri, Jun 20
STL
St. Louis
SEA
Seattle
₩388,900 Roundtrip, found 2 days ago
₩388,900
Roundtrip
found 2 days ago
Select Delta flight, departing Sat, Jun 14 from St. Louis to Seattle, returning Fri, Jun 20, priced at ₩388,900 found 2 days ago
United
Sat, May 3 - Mon, May 12
STL
St. Louis
SEA
Seattle
₩390,400 Roundtrip, found 5 days ago
₩390,400
Roundtrip
found 5 days ago
Select United flight, departing Sat, May 3 from St. Louis to Seattle, returning Mon, May 12, priced at ₩390,400 found 5 days ago
Delta
Sat, May 3 - Mon, May 12
STL
St. Louis
SEA
Seattle
₩398,800 Roundtrip, found 5 days ago
₩398,800
Roundtrip
found 5 days ago
Select Delta flight, departing Sat, May 3 from St. Louis to Seattle, returning Mon, May 12, priced at ₩398,800 found 5 days ago
American Airlines
Sat, Jun 14 - Fri, Jun 20
STL
St. Louis
SEA
Seattle
₩416,100 Roundtrip, found 2 days ago
₩416,100
Roundtrip
found 2 days ago
Select American Airlines flight, departing Sat, Jun 14 from St. Louis to Seattle, returning Fri, Jun 20, priced at ₩416,100 found 2 days ago
Delta
Wed, Aug 20 - Sat, Aug 23
STL
St. Louis
SEA
Seattle
₩418,000 Roundtrip, found 6 days ago
₩418,000
Roundtrip
found 6 days ago
Select Delta flight, departing Wed, Aug 20 from St. Louis to Seattle, returning Sat, Aug 23, priced at ₩418,000 found 6 days ago
Delta
Wed, Aug 20 - Sat, Aug 23
STL
St. Louis
SEA
Seattle
₩425,300 Roundtrip, found 6 days ago
₩425,300
Roundtrip
found 6 days ago
Select Delta flight, departing Wed, Aug 20 from St. Louis to Seattle, returning Sat, Aug 23, priced at ₩425,300 found 6 days ago
Delta
Wed, Aug 20 - Sat, Aug 23
STL
St. Louis
SEA
Seattle
₩438,600 Roundtrip, found 6 days ago
₩438,600
Roundtrip
found 6 days ago
Select Delta flight, departing Wed, Aug 20 from St. Louis to Seattle, returning Sat, Aug 23, priced at ₩438,600 found 6 days ago
Flights from St. Louis (STL) to Seattle (SEA)
Origin airport
Lambert-St. Louis Intl.
Destination airport
Seattle - Tacoma Intl.
Airlines serving
American Airlines, Delta, United
Roundtrip price
₩366,400
Distance
2728 km

St. Louis to Seattle Flights

Sometimes you just need to get out of town or maybe you’re looking for a change of scenery. Regardless of the reason, a flight from St. Louis to Seattle will do just the trick! Go on, plan to see all the famous landmarks and eat your weight in the local cuisine. Your trip is beckoning, so answer the call by packing your suitcase and filling your travel itinerary with exploring Seattle.

Whether you’re flying for business or jet-setting on your personal time, you’ve come to the right place. Here at Expedia.com, we’ll pair you up with STL to SEA flights that won’t make your bank account wince. Ready to temporarily leave behind St. Louis for new horizons? Browse through our cheap airfare, and filter by flight times and dates until you find just what you had in mind. From flights without layovers to ones that arrive early in the morning, you’ll come across plane tickets that suit your travel preferences. You can even bundle your flight to SEA with hotels and car rentals to score even bigger savings.

All set to hit the clouds? Book your travel arrangements with us today and have left-over money to put toward your travel outings and adventures.

Frequently asked questions

How much is a flight from St. Louis Lambert International Airport to Sea-Tac Airport?
If you’re traveling between Lambert-St. Louis Intl. Airport (STL) and SEA, round-trip flights start from ₩366,400. This price is based on airfares available within the last 7 days on Expedia for flights departing within the next year, so don’t delay. Book now and save yourself money and time. Prices and availability are subject to change. Additional terms apply.
Do I need to pay a cancellation fee if I cancel my flight from Lambert-St. Louis Intl. Airport (STL) to Seattle - Tacoma Intl. Airport (SEA)?
Each airline has different terms and conditions. If you decide to cancel your vacation, visit our Customer Service Portal.
How do I find cheap flights from St. Louis Lambert International Airport to SEA that have flexible change policies?
Many airlines offer the option to reschedule your flight without a change fee. All you pay is the difference between the original flight and the new flight. When you’re searching for Lambert Field to Sea-Tac Airport flights, you’ll see a “no change fees” filter for you to select.
How far is the flight from St. Louis Lambert International Airport to Sea-Tac Airport?
It’s around 2,700 kilometers between STL and SEA, so you’ll be strapped into your seat for a while. Keep yourself entertained with things like your e-reader or a thrilling novel.
Which airlines fly direct from Lambert-St. Louis Intl. Airport (STL) to Seattle - Tacoma Intl. Airport (SEA)?
Offering 30 flights each month, Alaska Airlines (AS) is a popular choice when flying directly from St. Louis Lambert International Airport to Sea-Tac Airport.
Are STL to Seattle - Tacoma Intl. Airport (SEA) flight tickets cheaper when they're purchased at the last minute?
Last-minute bookings from St. Louis Lambert International Airport to Sea-Tac Airport can be hit-or-miss. It is possible to find a bargain, but then again, you could miss out altogether! If you’d rather play it safe and start planning your trip ahead of time, Expedia compares flight deals up to 12 months in advance. Just bear in mind that not all airlines publish their prices so far in advance. Our advice? Check back often as prices are updated regularly.

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