$90 Cheap Flights from Seattle (SEA) to St. Louis (STL)

View $90 flight on Sat, Aug 30, 2025Opens in a new window

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Find available prices by choosing your travel dates.

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

Prices were available within the past 7 days and start at $90 for one-way flights and $180 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

United
Wed, Aug 20 - Wed, Aug 27
SEA
Seattle
STL
St. Louis
$180 Roundtrip, just found
$180
Roundtrip
just found
Select United flight, departing Wed, Aug 20 from Seattle to St. Louis, returning Wed, Aug 27, priced at $180 just found
United
Wed, Oct 15 - Mon, Oct 20
SEA
Seattle
STL
St. Louis
$184 Roundtrip, found 4 hours ago
$184
Roundtrip
found 4 hours ago
Select United flight, departing Wed, Oct 15 from Seattle to St. Louis, returning Mon, Oct 20, priced at $184 found 4 hours ago
United
Wed, Sep 10 - Wed, Sep 24
SEA
Seattle
STL
St. Louis
$186 Roundtrip, found 3 hours ago
$186
Roundtrip
found 3 hours ago
Select United flight, departing Wed, Sep 10 from Seattle to St. Louis, returning Wed, Sep 24, priced at $186 found 3 hours ago
American Airlines
Mon, Aug 18 - Sat, Aug 23
SEA
Seattle
STL
St. Louis
$187 Roundtrip, just found
$187
Roundtrip
just found
Select American Airlines flight, departing Mon, Aug 18 from Seattle to St. Louis, returning Sat, Aug 23, priced at $187 just found
Southwest Airlines
Wed, May 28 - Sat, May 31
SEA
Seattle
STL
St. Louis
$189 Roundtrip, found 14 hours ago
$189
Roundtrip
found 14 hours ago
Select Southwest Airlines flight, departing Wed, May 28 from Seattle to St. Louis, returning Sat, May 31, priced at $189 found 14 hours ago
Southwest Airlines
Thu, Jun 12 - Sun, Jun 15
SEA
Seattle
STL
St. Louis
$189 Roundtrip, just found
$189
Roundtrip
just found
Select Southwest Airlines flight, departing Thu, Jun 12 from Seattle to St. Louis, returning Sun, Jun 15, priced at $189 just found
Delta
Wed, Jun 11 - Thu, Jun 19
SEA
Seattle
STL
St. Louis
$189 Roundtrip, just found
$189
Roundtrip
just found
Select Delta flight, departing Wed, Jun 11 from Seattle to St. Louis, returning Thu, Jun 19, priced at $189 just found
American Airlines
Mon, Aug 18 - Sat, Aug 23
SEA
Seattle
STL
St. Louis
$189 Roundtrip, just found
$189
Roundtrip
just found
Select American Airlines flight, departing Mon, Aug 18 from Seattle to St. Louis, returning Sat, Aug 23, priced at $189 just found
American Airlines
Wed, Sep 10 - Wed, Sep 24
SEA
Seattle
STL
St. Louis
$190 Roundtrip, found 3 hours ago
$190
Roundtrip
found 3 hours ago
Select American Airlines flight, departing Wed, Sep 10 from Seattle to St. Louis, returning Wed, Sep 24, priced at $190 found 3 hours ago
Frontier Airlines
Thu, May 29 - Sat, Jun 7
SEA
Seattle
STL
St. Louis
$198 Roundtrip, found 1 hour ago
$198
Roundtrip
found 1 hour ago
Select Frontier Airlines flight, departing Thu, May 29 from Seattle to St. Louis, returning Sat, Jun 7, priced at $198 found 1 hour ago

Frequently asked questions

How much does a flight from Seattle - Tacoma Intl. Airport (SEA) to Lambert-St. Louis Intl. Airport (STL) cost?
Book cheap return fares starting from $246 from Seattle - Tacoma Intl. Airport (SEA) to Lambert-St. Louis Intl. Airport (STL). This information is based on the cheapest price found on Expedia for this return journey departing within the next three months. This airfare is for a Alaska Airlines flight leaving SEA on May 5 2025 and touching down at STL. The price was last updated on April 22 2025 and has not changed since.
What is the cheapest month to fly from SEA to STL?
The cheapest flights from SEA to STL are usually during off-peak season, when demand is lower. To save money, avoid flying during public holidays, school breaks and major local events.
Which airlines fly direct from Seattle - Tacoma Intl. Airport (SEA) to Lambert-St. Louis Intl. Airport (STL)?
Hop on a nonstop flight with Alaska Airlines and head straight from Seattle - Tacoma Intl. Airport (SEA) to Lambert-St. Louis Intl. Airport (STL).
What is the cheapest airline that flies from SEA to STL?
Take off from SEA to STL with Alaska Airlines. This airline currently offers the lowest one-way fare on this route, starting at $119. This fare is based on the lowest price found on Expedia departing within the next three months. The flight takes off from SEA on May 28 2025. Prices were last updated on April 22 2025 and have not changed since.
How many flights per day from Seattle - Tacoma Intl. Airport (SEA) to Lambert-St. Louis Intl. Airport (STL)?
On average, just 1 nonstop flight departs each day from Seattle - Tacoma Intl. Airport (SEA) to Lambert-St. Louis Intl. Airport (STL). Looking for more options? Use our filter tool to find flights with layovers and squeeze in a visit to another city along the way.
What are the most popular departure times for flights from Seattle - Tacoma Intl. Airport (SEA) to Lambert-St. Louis Intl. Airport (STL)?
More people fly between SEA and STL at 8 AM than at any other point in the day. Prefer a quieter experience? Travel outside of rush hours and it’s possible you’ll save on your fare as well.
What day of the week has the most flights from SEA to STL?
If you depart on a Friday, you’ll get the largest range of choices for flights from Seattle - Tacoma Intl. Airport (SEA) to Lambert-St. Louis Intl. Airport (STL).
What is the earliest flight from Seattle - Tacoma Intl. Airport (SEA) to Lambert-St. Louis Intl. Airport (STL)?
Seattle - Tacoma Intl. Airport (SEA)’s earliest flight to Lambert-St. Louis Intl. Airport (STL) takes off at approximately 8:00AM UTC-8. With a flight time of 3h 53m, you’ll touch down at around 1:53PM UTC-6.
How long does it take to fly from Seattle - Tacoma Intl. Airport (SEA) to Lambert-St. Louis Intl. Airport (STL)?
The average flight time from SEA to STL is 3 hours and 52 minutes, covering a total distance of 1,700 mi.
What airline has the least delays from SEA to STL?
American Airlines has the best performance for on-time direct flights from Seattle - Tacoma Intl. Airport (SEA) to Lambert-St. Louis Intl. Airport (STL), with an on-time rating of 98%. Use the Expedia App to look up your flight status before you jet off and receive notifications about any changes.
What is the best time to fly from Seattle - Tacoma Intl. Airport (SEA) to Lambert-St. Louis Intl. Airport (STL)?
To land at Lambert-St. Louis Intl. Airport (STL) on schedule, pick a flight that leaves Seattle - Tacoma Intl. Airport (SEA) before 3 PM. The likelihood of cancellations is 22% higher, on average, for departures after this time.**Most reliable time of the day and month to travel recommendation is based on January through August 2024 flight status data sourced from OAG’s global flight data platform.
What airports do you fly into for St. Louis from Seattle - Tacoma Intl. Airport (SEA)?
If you’re traveling on a direct flight from Seattle - Tacoma Intl. Airport (SEA) to St. Louis, Lambert-St. Louis Intl. Airport (STL) is the only airport you can touch down at.
Is it cheaper to buy a plane ticket from Seattle - Tacoma Intl. Airport (SEA) to Lambert-St. Louis Intl. Airport (STL) last-minute?
Last-minute fares from SEA to STL are generally more expensive. To secure the lowest prices, start looking for flights well ahead of time. That said, if you can play around with your travel dates, you may land a cheap fare right before your journey.
Is it cheaper to book a SEA to STL flight and hotel package?
You can save money by booking a SEA to STL flight and hotel package compared to booking separately. In fact, you could save hundreds of dollars by bundling with Expedia. And it’s simple to manage it all in one place. After selecting your ideal accommodations and flights, consider other add-ons like car rentals, tours and activities.
Can I cancel or change the date of my flight from Seattle - Tacoma Intl. Airport (SEA) to Lambert-St. Louis Intl. Airport (STL)?
In most instances, you can cancel or modify your SEA to STL flight. However, there may be additional fees, especially if you made your booking over 24 hours ago. Double-check your itinerary for the airline’s rules and fees on flight changes, or if you’d like more information, visit our Customer Service portal.
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