CA $120 Cheap Flights from St. Louis (STL) to Seattle (SEA)

Popular airlines from Lambert-St. Louis International Airport (STL) to Seattle-Tacoma International Airport (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 $120 for one-way flights and CA $240 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Delta
Delta
Delta
Delta
Alaska Airlines
Delta
Alaska Airlines
Hawaiian Airlines
United
American Airlines

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

October is typically the cheapest month to fly

From CA $190 - CA $301 per traveller.

Graph displaying average flight prices per month

Flight from St. Louis to Seattle (STL - SEA) route information
Origin airport
Lambert-St. Louis Intl.
Destination airport
Seattle - Tacoma Intl.
Roundtrip price
CA $240
Distance
2728 km
Average flight time
3 hours 11 mins

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, Southwest Airlines, Hawaiian Airlines, Air Tahiti Nui, United Airlines 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 $240 rising to CA $437.  

Here are more money-saving tips: 

  • Fly in October 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 STL to SEA?
Pack your bags, because round-trip journeys from Lambert-St. Louis Intl. Airport (STL) to Sea-Tac Airport start from CA $240. That's based on fares listed within the last 7 days on Expedia for flights departing within the next year. Prices can increase quickly, so book today to lock in the best deal. 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 Field to Sea-Tac Airport?
The majority of flights can be cancelled online, but every air carrier has its own terms and conditions. If you do have to cancel your flight, check out our Customer Service Portal and follow the instructions.
How do I find cheap flights from Lambert Field to Seattle - Tacoma Intl. Airport (SEA) that have flexible change policies?
Select our "No change fees" filter to find flexible ticketing options for your flight from Lambert Field to Sea-Tac Airport. This allows you to snag a fantastic price in advance and still have the freedom to make changes without any extra fees. Just keep in mind that fare differences may still apply.
How many hours is the flight from STL to Seattle - Tacoma Intl. Airport (SEA)?
The flight time from STL to Sea-Tac Airport is about 7 hours and 29 minutes. Put your earphones in, listen to your favourite tunes and the hours will fly by.
How far is the flight from Lambert-St. Louis Intl. Airport (STL) to SEA?
The flying distance between Lambert Field (STL) and Seattle - Tacoma Intl. Airport (SEA) (SEA) is 2,700 kilometres. Work your way through your travel song playlist or get stuck into a book and the journey will fly by.
Which airlines fly direct from Lambert Field to Seattle - Tacoma Intl. Airport (SEA)?
Check out the airfares with Alaska Airlines (AS) if you want to travel directly from Lambert-St. Louis Intl. Airport (STL) to SEA. This airline offers 30 monthly flights, so you're sure to find one that suits your schedule.
Are Lambert-St. Louis Intl. Airport (STL) to Sea-Tac Airport flight tickets cheaper when they're purchased at the last minute?
Last-minute bookings from Lambert Field to SEA can be hit-or-miss. You may be able to find a bargain, but then again, you could miss out altogether! If you'd prefer to start your trip planning early on, Expedia compares flight deals up to 12 months in advance. Just keep in mind that not all airlines list their prices so far in advance. Our suggestion? Check back often as updates are made frequently.

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