S$128 Cheap Flights from Seattle to St. Louis

View S$128 flight on Thu, 3 Jul,2025Opens in a new window

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

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

Prices were available within the past 7 days and start at S$128 for one-way flights and S$340 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Delta
Tue, 13 May - Tue, 20 May
SEA
Seattle
STL
St. Louis
S$340 Return, found 3 days ago
S$340
Return
found 3 days ago
Select Delta flight, departing Tue, 13 May from Seattle to St. Louis, returning Tue, 20 May, priced at S$340 found 3 days ago
Delta
Tue, 13 May - Tue, 20 May
SEA
Seattle
STL
St. Louis
S$387 Return, found 3 days ago
S$387
Return
found 3 days ago
Select Delta flight, departing Tue, 13 May from Seattle to St. Louis, returning Tue, 20 May, priced at S$387 found 3 days ago
American Airlines
Tue, 13 May - Tue, 20 May
SEA
Seattle
STL
St. Louis
S$401 Return, found 3 days ago
S$401
Return
found 3 days ago
Select American Airlines flight, departing Tue, 13 May from Seattle to St. Louis, returning Tue, 20 May, priced at S$401 found 3 days ago
American Airlines
Tue, 13 May - Tue, 20 May
SEA
Seattle
STL
St. Louis
S$433 Return, found 3 days ago
S$433
Return
found 3 days ago
Select American Airlines flight, departing Tue, 13 May from Seattle to St. Louis, returning Tue, 20 May, priced at S$433 found 3 days ago
Delta
Tue, 13 May - Tue, 20 May
SEA
Seattle
STL
St. Louis
S$441 Return, found 3 days ago
S$441
Return
found 3 days ago
Select Delta flight, departing Tue, 13 May from Seattle to St. Louis, returning Tue, 20 May, priced at S$441 found 3 days ago
American Airlines
Tue, 13 May - Tue, 20 May
SEA
Seattle
STL
St. Louis
S$460 Return, found 3 days ago
S$460
Return
found 3 days ago
Select American Airlines flight, departing Tue, 13 May from Seattle to St. Louis, returning Tue, 20 May, priced at S$460 found 3 days ago
Delta
Tue, 13 May - Tue, 20 May
SEA
Seattle
STL
St. Louis
S$467 Return, found 3 days ago
S$467
Return
found 3 days ago
Select Delta flight, departing Tue, 13 May from Seattle to St. Louis, returning Tue, 20 May, priced at S$467 found 3 days ago
Delta
Tue, 13 May - Tue, 20 May
SEA
Seattle
STL
St. Louis
S$473 Return, found 3 days ago
S$473
Return
found 3 days ago
Select Delta flight, departing Tue, 13 May from Seattle to St. Louis, returning Tue, 20 May, priced at S$473 found 3 days ago
Delta
Thu, 3 Jul - Sun, 13 Jul
SEA
Seattle
STL
St. Louis
S$483 Return, found 2 days ago
S$483
Return
found 2 days ago
Select Delta flight, departing Thu, 3 Jul from Seattle to St. Louis, returning Sun, 13 Jul, priced at S$483 found 2 days ago
United
Tue, 13 May - Tue, 20 May
SEA
Seattle
STL
St. Louis
S$519 Return, found 3 days ago
S$519
Return
found 3 days ago
Select United flight, departing Tue, 13 May from Seattle to St. Louis, returning Tue, 20 May, priced at S$519 found 3 days ago
Seattle to St. Louis route information
Origin airport
Seattle - Tacoma Intl.
Destination airport
Lambert-St. Louis Intl.
Return price
S$340
Distance
2728 km

Flights from Seattle to St. Louis

When looking for plane tickets from Seattle to St. Louis, the ease and convenience of using Expedia simply can’t be beat. With tons of departure points and flights options from the top airline carriers, Expedia gives you the widest array of cheap flights to St. Louis. Look for SEA to STL airfare with the assurance that you have the largest online travel agency working for you.

Expedia lets you search across the largest number of airlines and St. Louis flights, which means that you’ll be able to find a great flight deal at the perfect travel date and time. Our simple-to-use booking engine makes looking for terrific bargains easy and hassle-free; just enter your travel dates and departure city, and let Expedia do the rest! Adjust your travel dates and explore connecting flights to find an even better deal on your Seattle St. Louis flight!

Browse through dozens of options and rest 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 Seattle to St. Louis trip. There’s simply no substitute for great prices suited to your travel needs and backed by excellent customer support.

Combine your St. Louis flight with a hotel and/or car rental for a package deal designed to save you even more money! Discover additional savings by booking in advance or find a last minute deal. There are tons of ways to save on your flights from Seattle to St. Louis with Expedia. Use us as your stop travel destination and have the confidence that you’re getting a bargain!

Frequently asked questions

How much is a flight from SEA to STL?
Based on fares listed within the last 7 days on Expedia for flights departing within the next year, round-trip flights between SEA and Lambert Field start from S$340. Book now to get the best price for your big adventure. Prices and availability are subject to change. Additional terms apply.
Do I need to pay a cancellation fee if I cancel my flight from SEA to Lambert-St. Louis Intl. Airport (STL)?
The majority of flights can be cancelled online, but whether you incur a fee differs between airlines. If you do have to cancel your getaway, follow the instructions in the Customer Service Portal.
How do I find cheap flights from Seattle - Tacoma Intl. Airport (SEA) to Lambert Field 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 Seattle - Tacoma Intl. Airport (SEA) to STL flights, you’ll see a “no change fees” filter for you to select.
How far is the flight from Seattle - Tacoma Intl. Airport (SEA) to Lambert-St. Louis Intl. Airport (STL)?
The flight distance from SeaTac to St. Louis is 2,700 kilometres. Pack yourself a drink, a snack and an interesting book to read. Keep yourself entertained and the hours will zip by.
Which airlines fly direct from Sea-Tac Airport to STL?
A favourite with many savvy travellers, Alaska Airlines (AS) operates 30 monthly flights from SEA to STL. Pick the one that fits in with your travel plans and book your ticket today.
Are SEA to St. Louis Lambert International Airport flight tickets cheaper when they're purchased at the last minute?
Booking your trip from Sea-Tac Airport to St. Louis Lambert International Airport at the last minute could be your ticket to an awesome deal. However, it might cost you a whole lot more! If you’d prefer not to take any chances, book well ahead of your departure date. In fact, Expedia has some of the best bargains as far ahead as 12 months in advance. If your preferred air carrier hasn’t released tickets yet, check back regularly as deals are updated on Expedia all the time.

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