Cheap Flights from St. Louis (STL) to Seattle (SEA) from HK$985~

View HK$985 flight on Wed, 8 Jul 2026Opens 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$985 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)

April is typically the cheapest month to fly

From HK$1,385 - HK$2,247 per traveller.

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.

Travel information

Origin airport
Lambert-St. Louis Intl.
Destination airport
Seattle - Tacoma Intl.
Distance
2728 km
Average flight time
3 hours 11 mins

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