HomeSearch by dateVacation packagesHotelsFlight dealsCar rentalTravel tips & news
St. Louis

$66+ Cheap flights from Seattle to St. Louis (SEA - STL)

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 10/25. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — STL
Oct 25 — Nov 11
Sat 10/25
Sat 11/1
1 adult, Economy
We work with more than 300 partners to bring you better travel deals

Find cheap flights from Seattle to St. Louis with Cheapflights

1. Tell us where you want to go

Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”

2. Select your favorite providers

We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.

3. Compare prices and book

Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.

Cheapflights Tip: The best prices from Seattle/Tacoma Intl to Lambert-St Louis are usually found in October or June, booked 57 days in advance, depart on a Thursday or Tuesday and return on a Tuesday

Cheap flight deals from Seattle to St. Louis

Discover tips and strategies to find the most affordable flight options for your journey from Seattle (SEA) to St. Louis (STL). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated September 25, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$208
(Kiwi.com)

One-way from

$66
(United Airlines)

Popular in

December

Cheapest in

October

Average price

$372

Good round-trip deal

$281 or less

Good one-way deal

$158 or less
Provider with most accurate pricing for Seattle/Tacoma Intl-Lambert-St Louis flight deals.
Search Deals
Provider most trusted by Cheapflights users for Seattle/Tacoma Intl-Lambert-St Louis flights.
Search Deals
From Seattle/Tacoma Intl to Lambert-St Louis
Search Deals
One-way flight from Seattle/Tacoma Intl to Lambert-St Louis
Search Deals
Highest demand for flights based on searches. 4% potential increase in price ($19 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease ($7 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in September 2025
Search Deals
Price to beat on a round-trip flight from Seattle/Tacoma Intl to Lambert-St Louis.
Search Deals
Price to beat on a one-way flight from Seattle/Tacoma Intl to Lambert-St Louis.
Search Deals

Find flight deals from Seattle to St. Louis

Cheapest flights from Seattle to St. Louis
Explore the most affordable flight options available from Seattle to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 25, 2025.

This Kiwi.com deal was found by Cheapflights users on 9/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/1312:58 pmSEA - STL
1 stop18h 09mFrontier
Tue 11/187:45 pmSTL - SEA
1 stop18h 22mFrontier
Deal found 9/22$208
This American Airlines deal was found by Cheapflights users on 9/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/512:59 amSEA - STL
1 stop7h 40mAmerican Airlines
Tue 11/115:17 amSTL - SEA
1 stop9h 53mAmerican Airlines
Deal found 9/23$209
This Frontier deal was found by Cheapflights users on 9/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/1011:43 amSEA - STL
2 stops19h 24mFrontier
Sun 11/167:45 pmSTL - SEA
2 stops14h 33mFrontier
Deal found 9/22$210
This Trip.com deal was found by Cheapflights users on 9/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/49:15 amSEA - STL
Nonstop4h 03mMultiple Airlines
Sat 11/87:45 pmSTL - SEA
1 stop18h 12mMultiple Airlines
Deal found 9/22$212
This Trip.com deal was found by Cheapflights users on 9/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/119:15 amSEA - STL
Nonstop4h 03mMultiple Airlines
Sat 11/157:45 pmSTL - SEA
1 stop18h 28mMultiple Airlines
Deal found 9/22$213
This Flightnetwork deal was found by Cheapflights users on 9/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Flightnetwork is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/47:00 amSEA - STL
1 stop24h 06mFrontier
Tue 10/77:52 pmSTL - SEA
1 stop18h 15mFrontier
Deal found 9/23$214
This Expedia deal was found by Cheapflights users on 9/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/188:43 pmSEA - STL
1 stop10h 24mMultiple Airlines
Sat 10/253:57 pmSTL - SEA
Nonstop4h 28mMultiple Airlines
Deal found 9/23$215
This Frontier deal was found by Cheapflights users on 9/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/121:37 pmSEA - STL
2 stops18h 35mFrontier
Sun 11/167:45 pmSTL - SEA
2 stops14h 33mFrontier
Deal found 9/22$216
This Delta deal was found by Cheapflights users on 9/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/81:30 pmSEA - STL
1 stop5h 53mDelta
Fri 11/146:34 amSTL - SEA
1 stop8h 22mDelta
Deal found 9/22$217
This Delta deal was found by Cheapflights users on 9/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/151:30 pmSEA - STL
1 stop8h 54mDelta
Fri 10/172:15 pmSTL - SEA
1 stop9h 48mDelta
Deal found 9/24$218
This Southwest deal was found by Cheapflights users on 9/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/166:30 amSEA - STL
2 stops14h 35mSouthwest
Sun 10/197:50 pmSTL - SEA
1 stop7h 35mSouthwest
Deal found 9/24$220
This Frontier deal was found by Cheapflights users on 9/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/178:43 pmSEA - STL
1 stop10h 24mFrontier
Mon 10/209:59 pmSTL - SEA
2 stops16h 08mFrontier
Deal found 9/24$221

Cheapflights Fare Finder

 
Customize your flight search to find flights from Seattle to St. Louis that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated September 25, 2025.
Use the filters below to find and compare flights from Seattle to St. Louis that are best for you.

Fly from

Seattle

Fly to

St. Louis

Route

Depart

Return

Price

SeattleSt. Louis

SEA - STL

SEASTL

Seattle/Tacoma Intl

Thu 12/4

6:15 am-5:05 pm

1 stop8h 50m

Lambert-St Louis

Sun 12/7

6:40 pm-12:30 am

1 stop7h 50m

$209

SeattleSt. Louis

SEA - STL

SEASTL

Seattle/Tacoma Intl

Wed 11/12

11:15 am-6:57 pm

1 stop5h 42m

Lambert-St Louis

Mon 11/17

7:47 pm-12:11 am

1 stop6h 24m

$217

SeattleSt. Louis

SEA - STL

SEASTL

Seattle/Tacoma Intl

Fri 10/17

8:43 pm-9:07 am

1 stop10h 24m

Lambert-St Louis

Mon 10/20

9:59 pm-12:07 pm

2 stops16h 08m

$221

SeattleSt. Louis

SEA - STL

SEASTL

Seattle/Tacoma Intl

Tue 11/11

9:15 am-3:18 pm

Nonstop4h 03m

Lambert-St Louis

Sat 11/15

7:00 am-9:33 am

Nonstop4h 33m

$237

SeattleSt. Louis

SEA - STL

SEASTL

Seattle/Tacoma Intl

Tue 11/11

9:15 am-3:18 pm

Nonstop4h 03m

Lambert-St Louis

Tue 11/18

7:00 am-9:33 am

Nonstop4h 33m

$237

SeattleSt. Louis

SEA - STL

SEASTL

Seattle/Tacoma Intl

Fri 10/17

11:55 pm-8:51 am

1 stop6h 56m

Lambert-St Louis

Mon 10/20

7:30 pm-11:59 pm

1 stop6h 29m

$238

SeattleSt. Louis

SEA - STL

SEASTL

Seattle/Tacoma Intl

Sat 11/8

9:15 am-3:18 pm

Nonstop4h 03m

Lambert-St Louis

Sun 11/16

4:14 pm-6:48 pm

Nonstop4h 34m

$247

SeattleSt. Louis

SEA - STL

SEASTL

Seattle/Tacoma Intl

Sun 11/9

6:05 pm-11:59 pm

Nonstop3h 54m

Lambert-St Louis

Tue 11/18

7:00 am-9:33 am

Nonstop4h 33m

$247

SeattleSt. Louis

SEA - STL

SEASTL

Seattle/Tacoma Intl

Thu 11/6

6:05 pm-11:59 pm

Nonstop3h 54m

Lambert-St Louis

Tue 11/11

7:00 am-9:33 am

Nonstop4h 33m

$247

SeattleSt. Louis

SEA - STL

SEASTL

Seattle/Tacoma Intl

Sat 11/8

9:15 am-3:18 pm

Nonstop4h 03m

Lambert-St Louis

Fri 11/14

4:14 pm-6:48 pm

Nonstop4h 34m

$247

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/24

Showing 1-10 of 21 results
1
2
3

Compare providers for flights from Seattle to St. Louis

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Seattle to St. Louis in September.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy2 starsTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
eDreamsPrice Accuracy3 starsTrust Score*3 stars
PricelinePrice Accuracy1 starTrust Score*3 stars
CheapTicketsDealPrice Accuracy3 starsTrust Score*3 stars
CheapflightsfaresPrice Accuracy2 starsTrust Score*1 star
JustAirTicketPrice Accuracy-Trust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on Seattle-St. Louis flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Seattle-St. Louis flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Seattle-St. Louis flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Seattle-St. Louis flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Seattle-St. Louis flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

The best insider tips for Seattle to St. Louis flights

Snippets provided in this section are AI-generated based on a summarization of Cheapflights-commissioned articles. The articles are presented as-is, for general informational purposes only, and may not be up-to-date. The opinions contained in the articles are original to the author and reflect their authentic experience, which may vary significantly from the experience of others.
Cheapflights partnered with top experts to bring you the best recommendations for your Seattle to St. Louis trip
Airports
SEA

Plan to arrive at SEA two hours before your flight. Use SEA Spot Saver for security appointments to reduce wait times.

Read more about SEAby Brandon Schultz
STL

Use the MetroLink light rail from STL for a convenient and economical way to reach downtown St. Louis in about 40 minutes.

Read more about STLby Taryn White
Our travel experts
Taryn White

Taryn White

Expert on STL

Taryn White

Taryn White

Taryn White is a freelance travel writer, digital creator, and travel advisor who has visited nearly 100 countries and all 50 states. She’s familiar with many airports and enjoys beach hopping, boutique hotels, spa experiences, and exploring local culture. Her work has appeared in Travel + Leisure, Condé Nast Traveler, National Geographic, Smithsonian Magazine, AFAR, and more.

Read more
Brandon Schultz

Brandon Schultz

Expert on SEA

Brandon Schultz

Brandon Schultz

Brandon Schultz is an award-winning food and travel writer based in New York City. His work has appeared in Forbes, AAA, Thrillist, Travel + Leisure, and The Daily Meal, among many others, and he is the author of 6 books, including 3 cookbooks.

Read more

Best time to book a flight from Seattle to St. Louis

Have a flexible travel schedule? Discover the best time to fly to St. Louis from Seattle with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from Seattle to St. Louis

How far ahead should I book a flight from Seattle to St. Louis?

Use this chart to determine the optimal time to book a round-trip flight from Seattle to St. Louis. Price data was last updated on September 19, 2025.

The best time to book flights from Seattle to St. Louis is 57 days before your desired departure date. The cost of your flight will likely increase significantly if you book two weeks in advance of your flight.

What is the cheapest month to book a flight from Seattle to St. Louis?

Currently, August is the cheapest month in which you can book a flight from Seattle to St. Louis (average of $311). Flying from Seattle to St. Louis in March is currently the most expensive (average of $356). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest time of day to fly from SEA to STL?

Find hourly flight availability from Seattle to St. Louis. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated September 25, 2025.

When flying from Seattle to St. Louis, the time of day you fly usually plays a role in the price. Save by searching for a flight in the evening, which can drop the price by up to 39% versus a flight in the morning.

What is the cheapest day to fly from Seattle to St. Louis?

Use this chart to determine the cheapest time to fly round-trip from Seattle to St. Louis. Price data was last updated on September 21, 2025.

Travelers seeking maximum savings on their Seattle to St. Louis flight should consider departing on Tuesday evenings when fares are most often at their lowest. Monday at noon flights should be avoided if possible as fares are typically the most expensive at this time.

Reviews of airlines servicing St. Louis

Get insights into the airlines that provide service to St. Louis. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to St. Louis. Reviews last updated September 25, 2025.
Peruse reviews from past customers who have flown with Alaska Airlines, Southwest, and Delta from Seattle to St. Louis to help guide your decision. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Alaska Airlines
8.0
Very good
10,000 reviews

Boarding

8.1

Crew

8.5

Overall

8.0

Comfort

7.8

Food

7.1

Entertainment

7.0

Reviews

1 / 20
8.0
Excellent

Anonymous,Sep 2025

SEA - MKE

The crew were excellent, flight good, but the actual space for a person to occupy for 4 hours seems to get smaller and smaller 🤣. I am not overweight, and average height….very uncomfortable,, especially when I couldn’t recliner the seat at all, and the pocket in front doesn’t accommodate a water bottle.
Alaska Airlines
8.0
Very good
10,000 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Boarding

8.1

Crew

8.5

Overall

8.0

Comfort

7.8

Food

7.1

Entertainment

7.0

Reviews

1 / 20
8.0
Excellent

Anonymous,Sep 2025

SEA - MKE

The crew were excellent, flight good, but the actual space for a person to occupy for 4 hours seems to get smaller and smaller 🤣. I am not overweight, and average height….very uncomfortable,, especially when I couldn’t recliner the seat at all, and the pocket in front doesn’t accommodate a water bottle.
Southwest
8.0
Very good
4,246 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Boarding

8.1

Crew

8.5

Overall

8.0

Comfort

7.8

Food

7.1

Entertainment

7.0

Reviews

1 / 20
8.0
Excellent

Anonymous,Sep 2025

SEA - MKE

The crew were excellent, flight good, but the actual space for a person to occupy for 4 hours seems to get smaller and smaller 🤣. I am not overweight, and average height….very uncomfortable,, especially when I couldn’t recliner the seat at all, and the pocket in front doesn’t accommodate a water bottle.
Delta
8.0
Very good
7,973 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Boarding

8.1

Crew

8.5

Overall

8.0

Comfort

7.8

Food

7.1

Entertainment

7.0

Reviews

1 / 20
8.0
Excellent

Anonymous,Sep 2025

SEA - MKE

The crew were excellent, flight good, but the actual space for a person to occupy for 4 hours seems to get smaller and smaller 🤣. I am not overweight, and average height….very uncomfortable,, especially when I couldn’t recliner the seat at all, and the pocket in front doesn’t accommodate a water bottle.
Hawaiian Airlines
7.8
Good
2,751 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Boarding

8.1

Crew

8.5

Overall

8.0

Comfort

7.8

Food

7.1

Entertainment

7.0

Reviews

1 / 20
8.0
Excellent

Anonymous,Sep 2025

SEA - MKE

The crew were excellent, flight good, but the actual space for a person to occupy for 4 hours seems to get smaller and smaller 🤣. I am not overweight, and average height….very uncomfortable,, especially when I couldn’t recliner the seat at all, and the pocket in front doesn’t accommodate a water bottle.
American Airlines
7.2
Good
10,000 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Boarding

8.1

Crew

8.5

Overall

8.0

Comfort

7.8

Food

7.1

Entertainment

7.0

Reviews

1 / 20
8.0
Excellent

Anonymous,Sep 2025

SEA - MKE

The crew were excellent, flight good, but the actual space for a person to occupy for 4 hours seems to get smaller and smaller 🤣. I am not overweight, and average height….very uncomfortable,, especially when I couldn’t recliner the seat at all, and the pocket in front doesn’t accommodate a water bottle.

Related info for your journey

Find useful and relevant information for your journey from Seattle to St. Louis. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • What airports do I use to fly from Seattle to St. Louis?

    If you book a flight from Seattle to St. Louis, you will be flying from Seattle/Tacoma Intl to Lambert-St Louis. Flights to Lambert-St Louis (STL) from Seattle/Tacoma Intl (SEA) take 3h 52m for a nonstop flight. There are 11 flights from Seattle/Tacoma Intl to St. Louis per day from 7 airlines.

  • How popular is this Seattle to St. Louis flight route?

    The Seattle/Tacoma Intl to Lambert-St Louis flight path was viewed by 6 users in the past month. Keep an eye out for changes in search interest prior to high and low season.

  • How long is the flight from Seattle to St. Louis?

    Southwest, Delta, and Frontier can get you from Seattle to St. Louis in just under 5h 42m. Your travel time can differ by up to 4h 42m. Airlines will cover a distance of 1704 mi. This flight may include one or multiple stops.

  • What are the cheapest airlines flying from Seattle to St. Louis round-trip?

    Cheapflights users have booked flights from Seattle to St. Louis round-trip from $137. Other airlines that can offer you cheap pricing are Delta, from $149, and American Airlines, from $186. These flights start at 65% lower than the current average price 3 months from now.

  • What are the most reliable airlines from Seattle to St. Louis?

    Looking for the most reliable airlines to get you to your destination on time? Our data shows these are most likely to get you from Seattle to St. Louis on time: Alaska Airlines (76%), Hawaiian Airlines (76%), American Airlines (68%).

  • What are the cheapest flights from Seattle to St. Louis?

    The cheapest flight price from Seattle to St. Louis is $128. On average you can expect to pay $298. The most popular route, (Seattle/Tacoma Intl - Lambert-St Louis), can usually be booked for $136.

  • Can I find deals for flights from Seattle to St. Louis that include hotel bookings?

    Yes. In addition to deals on Seattle to St. Louis flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Seattle to St. Louis?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Seattle to St. Louis.

  • Can I find deals for business class flights from Seattle to St. Louis?

    Yes. Cheapflights offers flight deals from Seattle to St. Louis by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from Seattle to St. Louis?

    Currently, August is the cheapest month in which you can book a flight from Seattle to St. Louis (average of $311). Flying from Seattle to St. Louis in March is currently the most expensive (average of $356). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

Traveling to a place near St. Louis?

Book flights to St. Louis if you plan to visit one of these locations
Edwardsville
O'Fallon
Fairview Heights
Maryland Heights
Collinsville
Eureka
Glencoe
St. Peters
Chesterfield
Alton
Farmington
Festus

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Alternative routes for Seattle to St. Louis

See prices for flight routes from nearby airports that may be better suited for you.
Seattle to Kansas City flights
Portland to Kansas City flights
Portland to St. Louis flights
Seattle to Springfield flights
Spokane to St. Louis flights
Spokane to Kansas City flights
Pullman to St. Louis flights
Seattle to Branson flights
Portland to Springfield flights
Seattle to Columbia flights
Spokane to Springfield flights
Seattle to Joplin flights
Pasco to Kansas City flights
Pasco to Springfield flights
Pasco to St. Louis flights
Portland to Columbia flights
Bellingham to Kansas City flights
Yakima to Springfield flights
Walla Walla to St. Louis flights
Pullman to Kansas City flights
Portland to Joplin flights
Portland to Branson flights
Bellingham to St. Louis flights
Seattle to Quincy flights

Top 7 airlines flying from Seattle to St. Louis

Discover the top 7 airlines that operate flights from Seattle to St. Louis. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated September 25, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$137Average$285FlexibilityNo cancel feeOn-time62%
DeltaCheapest$149Average$300FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$186Average$453FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$186Average$381FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$216Average$371FlexibilityNo cancel feeOn-time69%
Hawaiian AirlinesCheapest$219Average$393FlexibilityNo cancel feeOn-time85%
Alaska AirlinesCheapest$246Average$421FlexibilityNo cancel feeOn-time75%

100% Free

Cheapflights is completely free to use, so you can start saving the moment you arrive.

Book with Flexibility

Our users can plan ahead with confidence and find flights with no change fees

Travel Smart

Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.