CA $126 Cheap Flights from St. Louis (STL) to Seattle (SEA)

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Cheap flights from St. Louis (STL) to Seattle (SEA)

Prices were available within the past 7 days and start at CA $126 for one-way flights and CA $298 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Alaska Airlines
Delta
Delta
Delta
Alaska Airlines
Alaska Airlines
Alaska Airlines
Delta
American Airlines
United
Flight from St. Louis to Seattle (STL - SEA) route information
Origin airport
Lambert-St. Louis Intl.
Destination airport
Seattle - Tacoma Intl.
Airlines serving
Alaska Airlines, American Airlines, Delta
Roundtrip price
CA $297
Distance
2728 km

St. Louis to Seattle Flights

The easy way to book your flights from St. Louis to Seattle 

With Expedia, it’s simple to find and book flights to Seattle from St. Louis whether you’re traveling for business or pleasure. Enter your travel dates, hit search, and choose your flight from 20 airlines that cover this route. There are American Airlines, Qatar Airways, JAL, Alaska Airlines, Hawaiian Airlines, Air Tahiti Nui nonstop flights to Seattle - Tacoma Intl., too.  

Choose your preferred carrier and cabin class with the advanced search tool and select your ideal departure time. Then, if you want, you can see just nonstop or refundable flights. And if you’re traveling last minute, just enter the date to check out flights from St. Louis to Seattle today, tomorrow, or this week.  

 

Save dollars with cheap flights from Lambert-St. Louis Intl., STL to Seattle - Tacoma Intl., SEA 

Sort your search results by price to find great deals on your flight from St. Louis to Seattle—you get all your cheapest options first. Grab yourself a bargain now—the lowest price on flights to Seattle from St. Louis currently is just CA $298 rising to CA $433.  

Here are more money-saving tips: 

  • Fly in April when flight prices are normally at their lowest 
  • Book about a month to 6 weeks before you travel for the best prices to Seattle  
  • Avoid peak season and weekends when flights can cost more
  • Early morning and late-night flights are sometimes cheaper, so try varying your travel times 
  • One surefire way to save money on your flight is to book your flight and hotel together with Expedia. Sometimes, the savings are so large that the flight is basically free! 

 

Reasons to choose Expedia for your flight to Seattle from St. Louis 

Whatever your destination, budget, or reason to travel, in just one quick search, you can choose from loads of flights, airlines, and cabin classes. The filters make it quick and easy to find your ideal flights, and if you choose one of the flexible options, you won’t be charged to change your flight. So book your flight to Seattle with Expedia today.

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 CA $298. 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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