SEA - STL

Find cheap flights from Seattle to St. Louis

1 adult
1 adult, Economy

KAYAK searches hundreds of travel sites at once for deals on flights to St. Louis

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Seattle to St. Louis, as well as popular online travel agencies
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Seattle to St. Louis, as well as popular online travel agencies
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Useful Info
Flights Deals

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

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Seattle to St. Louis that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from Seattle to St. Louis

American Airlines Logo
SEA-STL
3h 52mdirect
American Airlines Logo
STL-SEA
4h 30mdirect
American Airlines
Find Deal
Qatar Airways Logo
SEA-STL
3h 56mdirect
Qatar Airways Logo
STL-SEA
4h 30mdirect
Qatar Airways
Find Deal
Alaska Airlines Logo
SEA-STL
3h 52mdirect
Alaska Airlines Logo
STL-SEA
4h 30mdirect
Alaska Airlines
Find Deal
Japan Airlines Logo
SEA-STL
3h 49mdirect
Japan Airlines Logo
STL-SEA
4h 30mdirect
Japan Airlines
Find Deal
Southwest Logo
SEA-STL
3h 50mdirect
Southwest Logo
STL-SEA
4h 20mdirect
Southwest
Find Deal
Finnair Logo
SEA-STL
3h 56mdirect
Finnair Logo
STL-SEA
4h 29mdirect
Finnair
Find Deal
Hawaiian Airlines Logo
SEA-STL
3h 52mdirect
Hawaiian Airlines Logo
STL-SEA
4h 30mdirect
Hawaiian Airlines
Find Deal
Air Tahiti Nui Logo
SEA-STL
3h 52mdirect
Air Tahiti Nui Logo
STL-SEA
4h 30mdirect
Air Tahiti Nui
Find Deal
Expert advice

Expert advice for your flight from Seattle to St. Louis

 
Snippets provided in this section are AI-generated based on a summarisation of KAYAK-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.
KAYAK teamed up with top travel experts to share the best tips for your journey.
Airports
SEA

Use the SEA Spot Saver for free expedited security screening from 4 a.m. to 10 p.m. at Checkpoints 2, 3, and 5.

Read more about SEAby Harriet Baskas
STL

Take the MetroLink Red Line for convenient access to downtown St. Louis from STL, avoiding rush hour traffic.

Read more about STLby Yulia Denisyuk
Our travel experts
Yulia Denisyuk

Yulia Denisyuk

Expert on STL

Yulia Denisyuk

Yulia Denisyuk

Yulia is a freelance journalist who’s dispatched from 90+ countries. Her work focuses on cultures, adventure trips and air travel, appearing in NatGeo, NYT, CNTraveler, and more. For past assignments, she’s stayed with nomads in Mongolia and learned the art of Imigongo in Rwanda. She’s based in Chicago; in winter she often questions that decision.

Read more
Harriet Baskas

Harriet Baskas

Expert on SEA

Harriet Baskas

Harriet Baskas

Harriet is an award-winning journalist who is happiest in an airport or an unusual museum. Her stories about airports, air travel, and the business of travel have appeared on NBC News, CNBC, USA TODAY, The Points Guy and other outlets. She is the creator of the StuckatTheAirport.com blog and the author of nine books. When not out on the road or exploring the latest airport amenities, she’s home in Seattle getting ready for the next adventure.

Read more
Useful Info

KAYAK's insights & trends for Seattle to St. Louis flights

Get data-powered insights and trends into flights from Seattle to St. Louis to help you find the cheapest flights, the best time to fly and much more.

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

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Seattle to St. Louis, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.

The cheapest month for flights from Seattle to St. Louis is September, where tickets cost C$ 432 (return) on average. On the other hand, the most expensive months are July and December, where the average cost of round-trip tickets is C$ 637 and C$ 637 respectively.

Can I save money by flying with a layover from Seattle to St. Louis?

The average round-trip price for all non-stop flights, flights with one layover, and flights with two layovers for the route found by users searching on KAYAK in the last 2 weeks.

Yes, flying with a layover may cost you more time, but you can also save money on the route, with a 1 stop layover the cheapest option at C$ 447 on average.

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

To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights from Seattle to St. Louis, removes the top 0.1% to account for outliers, and then takes the average of all the values for each week.

To get a below average price on the flight from Seattle to St. Louis, you should book around 3 weeks before departure. For the absolute cheapest price, our data suggests you should book 21 weeks before departure.


Good to know

Low seasonJanuary
High seasonJune
Best time to beat the crowds (5% less expensive on average)
Most popular time to fly (4% more expensive on average)

When to book flights from Seattle to St. Louis

Are your dates flexible? Find out the best times to travel from Seattle to St. Louis based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price
KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or round-trips with a duration up to 40 days. While we try to provide actual minimum prices for each date, some prices are predictions and actual prices may differ.

FAQs for booking flights from Seattle to St. Louis

  • Where can I find car rentals from St. Louis Lambert International Airport (STL)?

    The use of car rentals is one of the most efficient methods of connecting travelers from STL Airport to the city center and St. Louis downtown. Car Rental Town-Saint Louis Airport is one car rental agency that provides affordable services to travelers arriving at STL Airport in St. Louis. This agency is located in STL Airport, along terminal 1.

  • How can I connect to St. Louis downtown from STL Airport?

    The use of the Metrolink bus system is the most efficient and inexpensive method of connecting travelers to St. Louis downtown from STL Airport. Travelers connecting to St. Louis downtown from STL Airport pay approximately $4.00 on Metrolink buses. Apart from buses, travelers can also use rental cars to connect to St. Louis downtown from STL Airport. Consider renting a car at Car Rental Town-Saint Louis Airport Agency.

  • Are there kid-friendly amenities on flights from Seattle to St. Louis?

    The availability of on-demand kid-friendly entertainment options on American Airlines makes it the most preferred airline for travelers flying from Seattle to St. Louis in the company of their kids. This airline offers free in-flight WI-FI services, which allows your kids to stream their favorite video games, TV shows, and music albums, eliminating boredom.

  • Which hotel can I stay in from STL Airport in St. Louis?

    There are several hotels where travelers landing at STL Airport can stay. One hotel that is easily accessible to travelers from STL Airport is the Quality Inn Airport. This hotel is located along Natural Bridge Rd, St. Louis, and it provides free airport shuttle services to customers.

  • Which airlines offer Wi-Fi service onboard planes from Seattle to St. Louis?

    Alaska Airlines, Hawaiian Airlines, and American Airlines offer inflight Wi-Fi service on the Seattle to St. Louis flight route.

  • Which aircraft models fly most regularly from Seattle to St. Louis?

    The Boeing 737 is the aircraft model that flies most regularly on the Seattle to St. Louis flight route.

  • Which airline alliances offer flights from Seattle to St. Louis?

    oneworld, and Star Alliance are the airline alliances operating flights between Seattle and St. Louis, with oneworld being the most commonly used for this route.

  • On which days can I fly direct from Seattle to St. Louis?

    There are direct flights from Seattle to St. Louis on a daily basis.

  • How does KAYAK find such low prices on flights from Seattle to St. Louis?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Seattle to St. Louis.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Seattle to St. Louis?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to St. Louis from Seattle is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from Seattle to St. Louis?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to St. Louis with an airline and back to Seattle with another airline.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Seattle to St. Louis?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to St. Louis from Seattle up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

KAYAK’s top tips for finding a cheap flight from Seattle to St. Louis

  • Despite having other airports that serve similar flights from Seattle to St. Louis, like Renton Municipal Airport and King County International Airport, travelers from Seattle prefer using Seattle-Tacoma International Airport (SEA) as their departure airport to St. Louis. This airport is widely preferred due to the availability of several cheaper means of transport that connect travelers from the city center and Seattle downtown to the airport, such as taxis, buses, and airport shuttles.
  • Travelers who plan to catch the earliest flight that departs SEA Airport for St. Louis should consider spending their night in a nearby hotel. One hotel that guarantees travelers quick access to SEA Airport is the DoubleTree by Hilton Hotel Seattle Airport. This hotel is located along International Blvd, Seattle, a 4min drive from SEA Airport and offers airport shuttle services.
  • Are you planning to travel from Seattle to St. Louis in the company of a person with reduced mobility? Worry no more. SEA Airport offers curb-to-aircraft services to persons with reduced mobility. All airlines serving flights from SEA Airport to St. Louis, like American Airlines, Qatar Airways, and Southwest, have deployed personnel across the airport to assist persons with reduced mobility.
  • Travelers who wish to shop before taking a flight from Seattle to St. Louis shouldn’t get worried. SeaTac Shopping Mall is one shopping mall that offers quality and affordable products to travelers flying from SEA Airport in Seattle. This shopping mall is located along International Blvd, SeaTac, just a walking distance from SEA Airport.
  • If you plan to take care of your stomach and have some rest as you wait for your flight from SEA Airport to St. Louis, consider visiting Dish D'lish Restaurant. Dish D'lish is one restaurant that offers the best food at an affordable price to travelers at SEA Airport as they wait for their flights to St. Louis.

Prefer to fly direct from Seattle to St. Louis?

Find which airlines fly direct from Seattle/Tacoma Intl Airport to Lambert-St Louis Airport, which days they fly and book direct flights.

Direct departures

Seattle/Tacoma Intl to Lambert-St Louis

Monday

Air Tahiti Nui,Alaska Airlines,American Airlines, +5 more

Air Tahiti Nui,Alaska Airlines, +6 more

Tuesday

Air Tahiti Nui,Alaska Airlines,American Airlines, +5 more

Air Tahiti Nui,Alaska Airlines, +6 more

Wednesday

Air Tahiti Nui,Alaska Airlines,American Airlines, +5 more

Air Tahiti Nui,Alaska Airlines, +6 more

Thursday

Air Tahiti Nui,Alaska Airlines,American Airlines, +6 more

Air Tahiti Nui,Alaska Airlines, +7 more

Friday

Air Tahiti Nui,Alaska Airlines,American Airlines, +5 more

Air Tahiti Nui,Alaska Airlines, +6 more

Saturday

Air Tahiti Nui,Alaska Airlines,American Airlines, +6 more

Air Tahiti Nui,Alaska Airlines, +7 more

Sunday

Air Tahiti Nui,Alaska Airlines,American Airlines, +6 more

Air Tahiti Nui,Alaska Airlines, +7 more

See more nonstop flights

Direct returns

Lambert-St Louis to Seattle/Tacoma Intl

Monday

Air Tahiti Nui,Alaska Airlines,American Airlines, +5 more

Air Tahiti Nui,Alaska Airlines, +6 more

Tuesday

Air Tahiti Nui,Alaska Airlines,American Airlines, +4 more

Air Tahiti Nui,Alaska Airlines, +5 more

Wednesday

Air Tahiti Nui,Alaska Airlines,American Airlines, +5 more

Air Tahiti Nui,Alaska Airlines, +6 more

Thursday

Air Tahiti Nui,Alaska Airlines,American Airlines, +5 more

Air Tahiti Nui,Alaska Airlines, +6 more

Friday

Air Tahiti Nui,Alaska Airlines,American Airlines, +4 more

Air Tahiti Nui,Alaska Airlines, +5 more

Saturday

Air Tahiti Nui,Alaska Airlines,American Airlines, +5 more

Air Tahiti Nui,Alaska Airlines, +6 more

Sunday

Air Tahiti Nui,Alaska Airlines,American Airlines, +5 more

Air Tahiti Nui,Alaska Airlines, +6 more

See more nonstop flights
See more nonstop flights

Top airline flying from Seattle to St. Louis

 
See real verified KAYAK customer reviews for airlines flying from Seattle to St. Louis. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from Seattle to St. Louis? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
5.9
FrontierOverall score based on 3295 reviews
4.8Food
4.5Entertainment
6.2Boarding
5.6Comfort
6.8Crew
Airline reviews

Book with frontier airlines with the mentality that they'll cancel your flight, kick you off and lose your luggage. Anything besides that is a win. Compare prices with other airlines (to include luggage) and if frontier is still worth it, book it but know all of their policies.

8.0 ExcellentTy, Jun 2025DFW - TPA
Read more Frontier reviews

Book with frontier airlines with the mentality that they'll cancel your flight, kick you off and lose your luggage. Anything besides that is a win. Compare prices with other airlines (to include luggage) and if frontier is still worth it, book it but know all of their policies.

You get what you pay for nothing essentially but a hard uncomfortable seat that doesn’t recline and kids screaming all around you and chaotic boarding and limited check bag weight allowance when compared to other airlines

I never got to experience the flight because they delayed my first flight and I missed this one. Then Frontier didn't want to help me rebook a flight to get me to my final destination.

The Boarding process in Denver was chaotic, and since the line was so long, we were lined up very far from the gate. If there were any announcements from the gate staff, we didn't hear them. The flight attendants were spectacular. The only negative part of the flight was sitting by a 2 1/2 year old who was unruly and unfortunately had parents that matched his behaviors. Also, the restaurants in Denver on the E concourse, they didn't have food (passengers could only order 1 item on the entire menu) or the restaurants had 12-14 people waiting for orders to be prepared and another 6 people waiting to order. If you have a layover in Denver and need to grab food, be prepared to visit the shops with pre-packaged sandwiches, or you can visit another concourse but it may take a while to transit throughout the airport.

I liked the turn-style feature at gate 209B at LAX. Very efficient process. The gate staff also made several, clearly directed announcements so I felt very informed.

Although an hour and a half early was told by staff at check in they had overbooked and could not check us in for the flight.

The crew was delayed because they came on another flight that was delayed due to weather 10pm flight left at 1.30 am The airline made no effort to align alternate crew

Plane was down graded and I lost my uncharged exit row with more leg room. No mention or offer of refund from podium. Flight attendant was nice to explain this happens often and that I could request a refund via online form submission. I did this and have heard nothing back.

Worst airline experience. They were rude and kept changing our seats and/or giving our seats away so our family didn’t get to sit with each other. Almost everyone we dealt with at both airports with this airline was rude. The app kept giving us wrong information making things take longer. Dealing with them before TSA can take close to an hour…longer than I’ve ever had to deal with before. Never using this airline again.

Horrendous. I do not recommend Frontier. The passengers lack manners and decency, and the flight attendants lack professionalism. If I wasn’t in a bind to fly with 48 hours notice for a job interview, I would not have selected a flight with Frontier and I never plan to fly with them in the future.

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

Information on your arrival and departure airports

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