S$489 Cheap Flights from St. Louis to Seattle

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Popular airlines from St. Louis Lambert Intl. Airport (STL) to Seattle

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

Prices were available within the past 7 days and start at S$489 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)

January is typically the cheapest month to fly

From S$164 - S$429 per traveller.

Frequently asked questions

How much is a flight from St. Louis Lambert International Airport to Sea-Tac Airport?
If you're travelling 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 holiday, 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 kilometres 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
2 hours 36 mins

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Perfect flights from St. Louis to Seattle

Your Journey from St. Louis to Seattle

Start your unforgettable journey with Expedia. Our broad selection of flights from St. Louis to Seattle caters to every travel need. Whether you're yearning for a romantic escape, a solo adventure, or a cultural immersion, we've got you covered.
 

Choosing Your Ideal Flight

With Expedia, you have access to a wide range of airlines, including United. Our selection of flights from Lambert-St. Louis Intl. to Seattle - Tacoma Intl. caters to every traveler's requirements, ensuring your journey aligns with your schedule. With options from 1 airlines, you're bound to find the perfect flight.
 

Maximizing Value with St. Louis to Seattle Flights

Experience the joy of finding cheap flights from Lambert-St. Louis Intl. to Seattle - Tacoma Intl. that fit your budget. Keep an eye out for our special deals and discounts, and check our flexible one-way fares from S$489 and roundtrip prices *.
 

Pre-Flight Essentials

Ensure a smooth journey from St. Louis to Seattle with Expedia. From information about check-in times and in-flight amenities to guidance on baggage policies, we provide all the essentials to prepare you for your flight.
 

Experience the Vibrant Seattle

Picture yourself stepping off the plane in Seattle and immersing yourself in the unique atmosphere of . From local markets to cultural festivals, each city offers its distinct charm. Make the most of your trip by exploring local attractions and indulging in the local cuisine. With Expedia, explore all this and more, tailored to your budget.
 

Added Convenience on Your St. Louis to Seattle Flight

Traveling with Expedia is more than just a flight. We offer details about in-flight amenities, baggage policies, and more to ensure a smooth and hassle-free journey. Choose from our variety of airlines and embark on a memorable journey from St. Louis to Seattle.
 

Beyond the Flight – Exploring Seattle

With Expedia, your adventure extends beyond the flight. Explore Seattle at your own pace by renting a car or booking a hotel. Discover hidden gems off the beaten path and create unforgettable memories.
 

Book Your Flight from St. Louis to Seattle with Confidence

Planning your next great adventure is a breeze with Expedia. Our user-friendly platform, unbeatable prices, and round-the-clock customer support make your travel experience seamless and stress-free. Embark on your journey from St. Louis to Seattle with confidence. Book your travel arrangements with Expedia today.
 
*Note: Prices may vary based on availability and are subject to change.
Perfect flights from St. Louis to Seattle

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*Available to Expedia members.