Cheap Flights from St. Louis (STL) to Seattle (SEA) from HK$1,058~

View HK$1,058 flight on Mon, 4 Aug 2025Opens in a new window

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

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

Prices were available within the past 7 days and start at HK$1,058 for one-way flights and for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Find the cheapest month to fly from St. Louis (STL) to Seattle (SEA)

September is typically the cheapest month to fly

From HK$1,083 - HK$1,654 per traveller.

Graph displaying average flight prices per month

St. Louis to Seattle route information
Origin airport
Lambert-St. Louis Intl.
Destination airport
Seattle - Tacoma Intl.
Distance
2728 km
Average flight time
3 hours 4 mins

Flights from St. Louis to Seattle

Book cheap flights from St. Louis (STL) to Seattle (SEA) on Expedia.com.hk. Find the best flight deals to destinations around the world for your next leisure or business travel on Expedia.com.hk.

Search for flights from St. Louis (STL) to Seattle (SEA) to find great flight deals suitable to your travel date and time. Expedia.com.hk flight booking search engine is simple to use and looking for cheap flights is as easy as a click of a mouse or on your mobile devices.

Be assured that you’re seeing the best price guaranteed! Our friendly customer service representatives are here to serve you 24 hours day to provide assistance and answer any questions that you may have about booking your St. Louis (STL) to Seattle (SEA) trip. Call us at 3077-4857 (direct number - 24 hours day for English).

Save more when combine your Seattle flight with a hotel for a package deal! Discover additional savings by booking in advance. Now you can find activities in Seattle and things to do in Seattle for your perfect vacation with Expedia Thing to Do.

If you would like to book flights to Seattle more flexibly, many prefer to purchase one-way tickets with options to take different airlines. A one way ticket to Seattle is HK$1,058 now!

 

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 . 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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