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$89+ 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 4/29. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — STL
Mar 30 — Apr 61
Sun 3/30
Sun 4/6
1 adult, Economy
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1. Tell us where you want to go
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Cheapflights Tip: The best prices from Seattle/Tacoma Intl to Lambert-St Louis are usually found in September or April, booked 81 days in advance, depart on a Thursday or Wednesday and return on a Wednesday

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 March 25, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$229
(Delta)

One-way from

$89
(Delta)

Popular in

December

Cheapest in

September

Average price

$347

Good round-trip deal

$338 or less

Good one-way deal

$148 or less
Provider with most accurate pricing for Seattle/Tacoma Intl-Lambert-St Louis flight deals.
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Provider most trusted by Cheapflights users for Seattle/Tacoma Intl-Lambert-St Louis flights.
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From Seattle/Tacoma Intl to Lambert-St Louis
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One-way flight from Seattle/Tacoma Intl to Lambert-St Louis
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Highest demand for flights based on searches. 7% potential increase in price ($32 potential increase over avg. RT price).
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Cheapest flight prices on average. 1% potential price decrease ($7 potential savings vs. average RT price).
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Average for round-trip flights in March 2025
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Price to beat on a round-trip flight from Seattle/Tacoma Intl to Lambert-St Louis.
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Price to beat on a one-way flight from Seattle/Tacoma Intl to Lambert-St Louis.
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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 March 25, 2025.

This Delta deal was found by Cheapflights users on 3/24. 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.
Thu 4/103:15 pmSEA - STL
1 stop5h 49mDelta
Mon 4/147:15 pmSTL - SEA
1 stop6h 47mDelta
Deal found 3/24$229
This Southwest deal was found by Cheapflights users on 3/23. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/249:35 amSEA - STL
1 stop8h 00mSouthwest
Sun 4/278:10 pmSTL - SEA
1 stop7h 10mSouthwest
Deal found 3/23$233
This Hawaiian Airlines deal was found by Cheapflights users on 3/24. 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 Hawaiian Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/36:03 pmSEA - STL
Nonstop3h 56mHawaiian Airlines
Tue 5/66:30 amSTL - SEA
Nonstop4h 24mHawaiian Airlines
Deal found 3/24$237
This United Airlines deal was found by Cheapflights users on 3/24. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/811:45 pmSEA - STL
1 stop9h 18mUnited Airlines
Wed 4/94:20 pmSTL - SEA
1 stop8h 30mUnited Airlines
Deal found 3/24$242
This Alaska Airlines deal was found by Cheapflights users on 3/23. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/146:04 pmSEA - STL
Nonstop3h 55mAlaska Airlines
Wed 4/166:44 amSTL - SEA
Nonstop4h 30mAlaska Airlines
Deal found 3/23$243
This American Airlines deal was found by Cheapflights users on 3/24. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/912:59 amSEA - STL
1 stop7h 34mAmerican Airlines
Tue 5/135:00 amSTL - SEA
1 stop7h 15mAmerican Airlines
Deal found 3/24$253
This Expedia deal was found by Cheapflights users on 3/23. 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.
Wed 6/46:04 pmSEA - STL
Nonstop4h 00mMultiple Airlines
Wed 6/117:24 pmSTL - SEA
1 stop7h 10mMultiple Airlines
Deal found 3/23$299
This CheapOair deal was found by Cheapflights users on 3/22. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/41:56 pmSEA - STL
1 stop17h 10mFrontier
Mon 4/76:38 pmSTL - SEA
1 stop16h 57mFrontier
Deal found 3/22$300
This Mytrip deal was found by Cheapflights users on 3/23. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/148:56 pmSEA - STL
3 stops18h 19mSpirit Airlines
Tue 4/226:10 pmSTL - SEA
3 stops43h 25mSpirit Airlines
Deal found 3/23$361

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 March 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 4/10

3:15 pm-11:04 pm

1 stop5h 49m

Lambert-St Louis

Mon 4/14

7:15 pm-12:02 am

1 stop6h 47m

$229

SeattleSt. Louis

SEA - STL

SEASTL

Seattle/Tacoma Intl

Thu 4/24

9:35 am-7:35 pm

1 stop8h 00m

Lambert-St Louis

Sun 4/27

8:10 pm-1:20 am

1 stop7h 10m

$233

SeattleSt. Louis

SEA - STL

SEASTL

Seattle/Tacoma Intl

Sat 5/3

6:03 pm-11:59 pm

Nonstop3h 56m

Lambert-St Louis

Tue 5/6

6:30 am-8:54 am

Nonstop4h 24m

$237

SeattleSt. Louis

SEA - STL

SEASTL

Seattle/Tacoma Intl

Tue 4/8

11:45 pm-11:03 am

1 stop9h 18m

Lambert-St Louis

Wed 4/9

4:20 pm-10:50 pm

1 stop8h 30m

$242

SeattleSt. Louis

SEA - STL

SEASTL

Seattle/Tacoma Intl

Mon 4/14

6:04 pm-11:59 pm

Nonstop3h 55m

Lambert-St Louis

Wed 4/16

6:44 am-9:14 am

Nonstop4h 30m

$243

SeattleSt. Louis

SEA - STL

SEASTL

Seattle/Tacoma Intl

Wed 4/9

12:59 am-10:33 am

1 stop7h 34m

Lambert-St Louis

Tue 5/13

5:00 am-10:15 am

1 stop7h 15m

$253

SeattleSt. Louis

SEA - STL

SEASTL

Seattle/Tacoma Intl

Wed 6/4

6:04 pm-12:04 am

Nonstop4h 00m

Lambert-St Louis

Wed 6/11

7:24 pm-12:34 am

1 stop7h 10m

$299

SeattleSt. Louis

SEA - STL

SEASTL

Seattle/Tacoma Intl

Fri 4/4

1:56 pm-9:06 am

1 stop17h 10m

Lambert-St Louis

Mon 4/7

6:38 pm-9:35 am

1 stop16h 57m

$300

SeattleSt. Louis

SEA - STL

SEASTL

Seattle/Tacoma Intl

Mon 4/14

8:56 pm-5:15 pm

3 stops18h 19m

Lambert-St Louis

Tue 4/22

6:10 pm-11:35 am

3 stops43h 25m

$361

SeattleSt. Louis

SEA - STL

SEASTL

Seattle/Tacoma Intl

Tue 4/29

5:30 am-1:28 pm

1 stop5h 58m

$89

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/24

Showing 1-10 of 19 results
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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 March.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
eDreamsPrice Accuracy3 starsTrust Score*3 stars
CheapTicketsDealPrice Accuracy3 starsTrust Score*3 stars
PricelinePrice Accuracy1 starTrust Score*3 stars
CheapflightsfaresPrice Accuracy3 starsTrust Score*2 stars
FareScanPrice Accuracy-Trust Score*3 stars
Justfly.comPrice Accuracy3 starsTrust Score*3 stars
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.

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 March 21, 2025.

The best time to book flights from Seattle to St. Louis is 81 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 March 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 40% 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 March 16, 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.

Weekly flight availability from Seattle to St. Louis

Explore weekly flight availability from Seattle to St. Louis. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated March 25, 2025.

The most flights from SEA to STL are scheduled on a Tuesday (11 on average). You will have fewer flight options on Thursday, which is when the least amount of flights are scheduled (1 on average).

Rainfall in St. Louis by month

Plan your trip to St. Louis by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in St. Louis ranges from 2.2 - 4.7 inches per month. May is typically the wettest month, when rainfall can reach 4.7 in. February is typically the driest time to visit St. Louis when rainfall is around 2.2 in.

Temperature in St. Louis by month

Plan your trip to St. Louis by taking into account the average temperature totals by month.

If weather is an important factor for your trip to St. Louis, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 80.6 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 32.0 F).

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 March 25, 2025.
Get a feel of what it's like to fly with Alaska Airlines, Southwest and Delta from Seattle to St. Louis by reading reviews from past customers. 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
9,782 reviews

Boarding

8.2

Comfort

7.9

Entertainment

7.1

Overall

8.0

Food

7.1

Crew

8.5

Reviews

1 / 20
8.0
Excellent

Anonymous,Aug 2024

SEA - LAS

Seats were not that comfy especially for someone with big hips 😥
Alaska Airlines
8.0
Very good
9,782 reviews
Alaska Airlines
8.0
Very good
9,782 reviews

Boarding

8.2

Comfort

7.9

Entertainment

7.1

Overall

8.0

Food

7.1

Crew

8.5

Reviews

1 / 20
8.0
Excellent

Anonymous,Aug 2024

SEA - LAS

Seats were not that comfy especially for someone with big hips 😥
Southwest
8.0
Very good
4,272 reviews
Alaska Airlines
8.0
Very good
9,782 reviews

Boarding

8.2

Comfort

7.9

Entertainment

7.1

Overall

8.0

Food

7.1

Crew

8.5

Reviews

1 / 20
8.0
Excellent

Anonymous,Aug 2024

SEA - LAS

Seats were not that comfy especially for someone with big hips 😥
Delta
8.0
Very good
7,890 reviews
Alaska Airlines
8.0
Very good
9,782 reviews

Boarding

8.2

Comfort

7.9

Entertainment

7.1

Overall

8.0

Food

7.1

Crew

8.5

Reviews

1 / 20
8.0
Excellent

Anonymous,Aug 2024

SEA - LAS

Seats were not that comfy especially for someone with big hips 😥
Hawaiian Airlines
7.9
Good
2,330 reviews
Alaska Airlines
8.0
Very good
9,782 reviews

Boarding

8.2

Comfort

7.9

Entertainment

7.1

Overall

8.0

Food

7.1

Crew

8.5

Reviews

1 / 20
8.0
Excellent

Anonymous,Aug 2024

SEA - LAS

Seats were not that comfy especially for someone with big hips 😥
United Airlines
7.4
Good
8,605 reviews
Alaska Airlines
8.0
Very good
9,782 reviews

Boarding

8.2

Comfort

7.9

Entertainment

7.1

Overall

8.0

Food

7.1

Crew

8.5

Reviews

1 / 20
8.0
Excellent

Anonymous,Aug 2024

SEA - LAS

Seats were not that comfy especially for someone with big hips 😥

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 53m for a nonstop flight. There are 4 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 5 users in the past month. Keep an eye out for changes in search interest prior to high and low season.

  • 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 $229. Other airlines that can offer you cheap pricing are Hawaiian Airlines, from $237, and United Airlines, from $242. These flights start at 40% lower than the current average price 3 months from now.

  • What are the cheapest airlines to fly from Seattle to St. Louis one-way?

    $89 is the cheapest one-way deal found within the past few days, from Delta. You may also be able to find cheap deals on Southwest and United Airlines, with prices starting from $99 and $114, respectively.

  • 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 (95%), Hawaiian Airlines (95%), Air Tahiti Nui (95%).

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

    The cheapest flight price from Seattle to St. Louis is $118. On average you can expect to pay $331. The most popular route, (Seattle/Tacoma Intl - Lambert-St Louis), can usually be booked for $178.

  • 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 Seattle?

Book flights to Seattle if you plan to visit one of these locations
Fenton
Fairview Heights
Maryland Heights
Collinsville
Wentzville
Eureka
St. Peters
Festus
Glencoe
Alton
Farmington
Chesterfield

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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 March 25, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$142Average$248FlexibilityNo cancel feeOn-time62%
DeltaCheapest$195Average$300FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$196Average$462FlexibilityNo cancel feeOn-time71%
United AirlinesCheapest$216Average$358FlexibilityNo cancel feeOn-time69%
Alaska AirlinesCheapest$236Average$420FlexibilityNo cancel feeOn-time75%
Hawaiian AirlinesCheapest$237Average$387FlexibilityNo cancel feeOn-time85%
SouthwestCheapest$276Average$529FlexibilityNo cancel feeOn-time63%
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