฿4,090 Cheap Flights from Seattle (SEA) to St. Louis (STL)

View ฿4,090 flight on Sun, 6 Sept 2026Opens in a new window

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

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

Prices were available within the past 7 days and start at ฿4,090 for one-way flights and ฿9,650 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Delta
Sun, 6 Sept - Thu, 10 Sept
SEA
Seattle
STL
St. Louis
฿9,650 Return, found 1 day ago
฿9,650
Return
found 1 day ago
Select Delta flight, departing Sun, 6 Sept from Seattle to St. Louis, returning Thu, 10 Sept, priced at ฿9,650 found 1 day ago
Delta
Wed, 24 Jun - Wed, 1 Jul
SEA
Seattle
STL
St. Louis
฿10,960 Return, found 2 days ago
฿10,960
Return
found 2 days ago
Select Delta flight, departing Wed, 24 Jun from Seattle to St. Louis, returning Wed, 1 Jul, priced at ฿10,960 found 2 days ago
American Airlines
Sun, 6 Sept - Thu, 10 Sept
SEA
Seattle
STL
St. Louis
฿11,120 Return, found 1 day ago
฿11,120
Return
found 1 day ago
Select American Airlines flight, departing Sun, 6 Sept from Seattle to St. Louis, returning Thu, 10 Sept, priced at ฿11,120 found 1 day ago
Delta
Sun, 6 Sept - Thu, 10 Sept
SEA
Seattle
STL
St. Louis
฿11,295 Return, found 1 day ago
฿11,295
Return
found 1 day ago
Select Delta flight, departing Sun, 6 Sept from Seattle to St. Louis, returning Thu, 10 Sept, priced at ฿11,295 found 1 day ago
Delta
Sun, 6 Sept - Thu, 10 Sept
SEA
Seattle
STL
St. Louis
฿11,460 Return, found 1 day ago
฿11,460
Return
found 1 day ago
Select Delta flight, departing Sun, 6 Sept from Seattle to St. Louis, returning Thu, 10 Sept, priced at ฿11,460 found 1 day ago
Delta
Sat, 2 May - Sat, 9 May
SEA
Seattle
STL
St. Louis
฿11,535 Return, found 5 days ago
฿11,535
Return
found 5 days ago
Select Delta flight, departing Sat, 2 May from Seattle to St. Louis, returning Sat, 9 May, priced at ฿11,535 found 5 days ago
Delta
Sat, 2 May - Sat, 9 May
SEA
Seattle
STL
St. Louis
฿11,725 Return, found 5 days ago
฿11,725
Return
found 5 days ago
Select Delta flight, departing Sat, 2 May from Seattle to St. Louis, returning Sat, 9 May, priced at ฿11,725 found 5 days ago
Delta
Sun, 6 Sept - Thu, 10 Sept
SEA
Seattle
STL
St. Louis
฿11,755 Return, found 1 day ago
฿11,755
Return
found 1 day ago
Select Delta flight, departing Sun, 6 Sept from Seattle to St. Louis, returning Thu, 10 Sept, priced at ฿11,755 found 1 day ago
Delta
Sat, 2 May - Sat, 9 May
SEA
Seattle
STL
St. Louis
฿11,865 Return, found 5 days ago
฿11,865
Return
found 5 days ago
Select Delta flight, departing Sat, 2 May from Seattle to St. Louis, returning Sat, 9 May, priced at ฿11,865 found 5 days ago
United
Sun, 6 Sept - Thu, 10 Sept
SEA
Seattle
STL
St. Louis
฿12,930 Return, found 1 day ago
฿12,930
Return
found 1 day ago
Select United flight, departing Sun, 6 Sept from Seattle to St. Louis, returning Thu, 10 Sept, priced at ฿12,930 found 1 day ago

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 ฿9,650. 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.

Travel information

Origin airport
Seattle - Tacoma Intl.
Destination airport
Lambert-St. Louis Intl.
Airlines serving
American Airlines, Delta, United
Return price
฿9,650
Distance
2728 km
Average flight time
6 hours 45 mins
*Available to Expedia members.