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 $246. Other airlines that can offer you cheap pricing are Alaska Airlines, from $249, and Frontier, from $252. These flights start at 37% lower than the current average price 3 months from now.

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

$125 is the cheapest one-way deal found within the past few days, from Hawaiian Airlines. You may also be able to find cheap deals on Southwest and Spirit Airlines, with prices starting from $128 and $134, respectively.

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.

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).

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

The cheapest flight price from Seattle to St. Louis is $124. On average you can expect to pay $322. The most popular route, (Seattle/Tacoma Intl - Lambert-St Louis), can usually be booked for $161.

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: Hawaiian Airlines (73%), Alaska Airlines (69%), Air Tahiti Nui (63%).

What are the most popular airlines that fly from Seattle to St. Louis?

American Airlines, Alaska Airlines and Delta are the most popular airlines when flying from Seattle to St. Louis.

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

Flying to your destination on a Saturday can be more expensive, but this shouldn’t discourage you from finding affordable options to get to St. Louis. Check prices with Cheapflights to find a great deal for your trip.

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

To save on the cost of your flight from Seattle to St. Louis, book at least 53 days before your planned departure. Booking around this time can save you about 94% on the cost of this flight compared to booking a flight leaving this week. We have found prices from $421 if you need a flight within two weeks. For flights within the next 72 hours, you can find tickets from as low as $454.

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

September can be a great time to fly to St. Louis from Seattle with a flight ticket averaging about $393. Cheapflights users have found deals in the month of September for as cheap as $216. The most expensive prices can be found in the month of December.

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 49m for a nonstop flight. There are 12 flights from Seattle/Tacoma Intl to St. Louis per day from 7 airlines.

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.

$125+ Flights from Seattle to St. Louis

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Cheapflights Tip: The best prices from Seattle/Tacoma Intl to Lambert-St Louis are usually found in September or October, booked 86 days in advance, depart on a Thursday or Friday and return on a Wednesday

Cheap flight deals from Seattle to St. Louis

Round-trip from	$246 (Kiwi.com)
One-way from	$125 (Hawaiian Airlines)
Popular in	December
Cheapest in	September
Average price	$457
Good round-trip deal	$289 or less
Good one-way deal	$171 or less

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. 5% potential increase in price ($20 potential increase over avg. RT price).

Search Deals

Cheapest flight prices on average. 1% potential price decrease ($8 potential savings vs. average RT price).

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Average for round-trip flights in July 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 July 11, 2025.

Thu 11/278:00 amSEA - STL

Nonstop3h 52mAlaska Airlines

Thu 12/117:00 amSTL - SEA

Nonstop4h 26mAlaska Airlines

Deal found 7/9

$243

Sat 8/238:38 amSEA - STL

Nonstop4h 01mHawaiian Airlines

Sat 8/306:00 amSTL - SEA

Nonstop4h 30mHawaiian Airlines

Deal found 7/9

$246

Sun 8/246:17 amSEA - STL

1 stop24h 54mFrontier

Tue 9/27:54 pmSTL - SEA

1 stop29h 07mFrontier

Deal found 7/10

$252

Fri 9/55:15 amSEA - STL

2 stops11h 20mSouthwest

Sun 9/76:05 pmSTL - SEA

1 stop9h 15mSouthwest

Deal found 7/9

$260

Wed 8/1311:30 pmSEA - STL

1 stop7h 30mAmerican Airlines

Sat 8/165:15 amSTL - SEA

1 stop7h 36mAmerican Airlines

Deal found 7/10

$267

Fri 11/285:45 amSEA - STL

1 stop5h 38mDelta

Tue 12/96:30 amSTL - SEA

1 stop8h 30mDelta

Deal found 7/10

$269

Tue 10/77:00 amSEA - STL

1 stop6h 44mUnited Airlines

Wed 11/191:35 pmSTL - SEA

2 stops11h 40mUnited Airlines

Deal found 7/10

$279

Sun 8/248:38 amSEA - STL

Nonstop4h 01mMultiple Airlines

Sun 8/318:10 amSTL - SEA

1 stop9h 05mMultiple Airlines

Deal found 7/10

$318

Best flights from Seattle to St. Louis
Discover carefully curated flight deals from Seattle to St. Louis that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated July 11, 2025.

Sat 8/238:38 amSEA - STL

Nonstop4h 01mHawaiian Airlines

Sat 8/306:00 amSTL - SEA

Nonstop4h 30mHawaiian Airlines

Deal found 7/9

$246

Fri 9/196:03 pmSEA - STL

Nonstop3h 56mAlaska Airlines

Tue 9/233:35 pmSTL - SEA

Nonstop4h 19mAlaska Airlines

Deal found 7/8

$249

Sun 8/246:17 amSEA - STL

1 stop24h 54mFrontier

Tue 9/27:54 pmSTL - SEA

1 stop29h 07mFrontier

Deal found 7/10

$252

Fri 9/55:15 amSEA - STL

2 stops11h 20mSouthwest

Sun 9/76:05 pmSTL - SEA

1 stop9h 15mSouthwest

Deal found 7/9

$260

Wed 8/1311:30 pmSEA - STL

1 stop7h 30mAmerican Airlines

Sat 8/165:15 amSTL - SEA

1 stop7h 36mAmerican Airlines

Deal found 7/10

$267

Tue 10/711:55 pmSEA - STL

1 stop6h 49mDelta

Mon 11/242:15 pmSTL - SEA

1 stop6h 15mDelta

Deal found 7/10

$269

Tue 10/77:00 amSEA - STL

1 stop6h 44mUnited Airlines

Tue 11/181:35 pmSTL - SEA

2 stops11h 40mUnited Airlines

Deal found 7/10

$279

Sun 8/248:38 amSEA - STL

Nonstop4h 01mMultiple Airlines

Sun 8/318:10 amSTL - SEA

1 stop9h 05mMultiple Airlines

Deal found 7/10

$318

Last-minute flights from Seattle to St. Louis
Discover last-minute flight deals from Seattle to St. Louis. Data last updated July 11, 2025 and is based on user searches.

Wed 7/166:00 amSEA - STL

1 stop6h 30mDelta

Wed 7/237:15 pmSTL - SEA

1 stop6h 44mDelta

Deal found 7/10

$497

Wed 7/1612:46 pmSEA - STL

Nonstop3h 49mAlaska Airlines

Wed 7/237:32 pmSTL - SEA

Nonstop4h 28mAlaska Airlines

Deal found 7/10

$512

Thu 7/177:48 pmSEA - STL

1 stop11h 23mFrontier

Mon 7/217:29 pmSTL - SEA

1 stop7h 05mFrontier

Deal found 7/9

$323

Mon 7/2111:55 pmSEA - STL

1 stop6h 01mAmerican Airlines

Tue 8/57:03 amSTL - SEA

1 stop9h 44mAmerican Airlines

Deal found 7/10

$358

Mon 7/2110:55 pmSEA - STL

1 stop7h 20mSouthwest

Mon 8/47:15 pmSTL - SEA

1 stop8h 10mSouthwest

Deal found 7/9

$403

Mon 7/2110:05 pmSEA - STL

2 stops12h 22mUnited Airlines

Tue 8/55:41 pmSTL - SEA

1 stop9h 18mUnited Airlines

Deal found 7/8

$409

Mon 7/216:06 pmSEA - STL

Nonstop3h 53mHawaiian Airlines

Tue 8/57:32 pmSTL - SEA

Nonstop4h 28mHawaiian Airlines

Deal found 7/10

$418

Mon 7/215:30 pmSEA - STL

3 stops16h 40mMultiple Airlines

Mon 8/410:47 amSTL - SEA

3 stops31h 38mMultiple Airlines

Deal found 7/9

$424

Mon 7/215:30 pmSEA - STL

2 stops21h 01mSpirit Airlines

Mon 8/410:47 amSTL - SEA

3 stops31h 38mSpirit Airlines

Deal found 7/9

$494

Wed 8/1311:30 pmSEA - STL

1 stop7h 30mAmerican Airlines

Sat 8/165:15 amSTL - SEA

1 stop7h 36mAmerican Airlines

Deal found 7/10

$267

Fri 8/1510:45 pmSEA - STL

1 stop8h 55mSouthwest

Sun 8/171:05 pmSTL - SEA

2 stops10h 25mSouthwest

Deal found 7/10

$277

Sat 8/238:38 amSEA - STL

Nonstop4h 01mHawaiian Airlines

Sat 8/306:00 amSTL - SEA

Nonstop4h 30mHawaiian Airlines

Deal found 7/9

$246

One-way flights from Seattle to St. Louis
Search for one-way flight options from Seattle to St. Louis. Find affordable one-way fares based on user searches. Data last updated July 11, 2025.

Wed 9/108:38 amSEA - STL

Nonstop4h 03mHawaiian Airlines

Deal found 7/10

$125

Thu 10/26:00 amSEA - STL

2 stops11h 15mSouthwest

Deal found 7/10

$128

Wed 8/65:30 pmSEA - STL

2 stops14h 22mSpirit Airlines

Deal found 7/9

$134

Tue 8/125:30 amSEA - STL

1 stop5h 59mDelta

Deal found 7/10

$135

Sun 8/177:48 pmSEA - STL

1 stop11h 23mFrontier

Deal found 7/10

$145

Tue 8/1212:46 amSEA - STL

1 stop10h 26mAmerican Airlines

Deal found 7/10

$167

Mon 9/1511:10 pmSEA - STL

2 stops13h 09mUnited Airlines

Deal found 7/10

$169

Tue 10/712:59 amSEA - STL

1 stop8h 52mAlaska Airlines

Deal found 7/9

$176

Wed 8/65:30 pmSEA - STL

3 stops16h 40mMultiple Airlines

Deal found 7/10

$196

Cheapflights Fare Finder

Use the filters below to find and compare flights from Seattle to St. Louis that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

SeattleSt. Louis

SEA - STL

SEASTL

Seattle/Tacoma Intl

Sat 8/23

8:38 am-2:39 pm

Nonstop4h 01m

Lambert-St Louis

Sat 8/30

6:00 am-8:30 am

Nonstop4h 30m

$246

SeattleSt. Louis

SEA - STL

SEASTL

Seattle/Tacoma Intl

Fri 9/19

6:03 pm-11:59 pm

Nonstop3h 56m

Lambert-St Louis

Tue 9/23

3:35 pm-5:54 pm

Nonstop4h 19m

$249

SeattleSt. Louis

SEA - STL

SEASTL

Seattle/Tacoma Intl

Sun 8/24

6:17 am-9:11 am

1 stop24h 54m

Lambert-St Louis

Tue 9/2

7:54 pm-11:01 pm

1 stop29h 07m

$252

SeattleSt. Louis

SEA - STL

SEASTL

Seattle/Tacoma Intl

Fri 9/5

5:15 am-6:35 pm

2 stops11h 20m

Lambert-St Louis

Sun 9/7

6:05 pm-1:20 am

1 stop9h 15m

$260

SeattleSt. Louis

SEA - STL

SEASTL

Seattle/Tacoma Intl

Wed 8/13

11:30 pm-9:00 am

1 stop7h 30m

Lambert-St Louis

Sat 8/16

5:15 am-10:51 am

1 stop7h 36m

$267

SeattleSt. Louis

SEA - STL

SEASTL

Seattle/Tacoma Intl

Tue 10/7

11:55 pm-8:44 am

1 stop6h 49m

Lambert-St Louis

Sat 11/22

5:30 pm-11:34 pm

1 stop8h 04m

$269

SeattleSt. Louis

SEA - STL

SEASTL

Seattle/Tacoma Intl

Tue 10/7

7:00 am-3:44 pm

1 stop6h 44m

Lambert-St Louis

Wed 11/19

1:35 pm-11:15 pm

2 stops11h 40m

$279

SeattleSt. Louis

SEA - STL

SEASTL

Seattle/Tacoma Intl

Sun 8/24

8:38 am-2:39 pm

Nonstop4h 01m

Lambert-St Louis

Sun 8/31

8:10 am-3:15 pm

1 stop9h 05m

$318

SeattleSt. Louis

SEA - STL

SEASTL

Seattle/Tacoma Intl

Wed 9/10

8:38 am-2:41 pm

Nonstop4h 03m

$125

SeattleSt. Louis

SEA - STL

SEASTL

Seattle/Tacoma Intl

Thu 10/2

6:00 am-7:15 pm

2 stops11h 15m

$128

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/10

Showing 1-10 of 17 results

The best insider tips for Seattle to St. Louis flights

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.

STL

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

Our travel experts

Taryn White

Expert on STL

Brandon Schultz

Expert on SEA

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?

The best time to book flights from Seattle to St. Louis is 52 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?

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?

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

The most flights from SEA to STL are scheduled on a Thursday (18 on average). You will have fewer flight options on Friday, which is when the least amount of flights are scheduled (7 on average).

Reviews of airlines servicing St. Louis

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

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

10,000 reviews

Alaska Airlines

8.0

Very good

10,000 reviews

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

4,249 reviews

Alaska Airlines

8.0

Very good

10,000 reviews

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

7,951 reviews

Alaska Airlines

8.0

Very good

10,000 reviews

Reviews

1 / 20

8.0

Excellent

Anonymous,Aug 2024

SEA - LAS

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

Hawaiian Airlines

7.8

Good

2,562 reviews

Alaska Airlines

8.0

Very good

10,000 reviews

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

8,846 reviews

Alaska Airlines

8.0

Very good

10,000 reviews

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

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 49m for a nonstop flight. There are 12 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 $246. Other airlines that can offer you cheap pricing are Alaska Airlines, from $249, and Frontier, from $252. These flights start at 37% lower than the current average price 3 months from now.
What are the cheapest airlines to fly from Seattle to St. Louis one-way?
$125 is the cheapest one-way deal found within the past few days, from Hawaiian Airlines. You may also be able to find cheap deals on Southwest and Spirit Airlines, with prices starting from $128 and $134, 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: Hawaiian Airlines (73%), Alaska Airlines (69%), Air Tahiti Nui (63%).
What are the cheapest flights from Seattle to St. Louis?
The cheapest flight price from Seattle to St. Louis is $124. On average you can expect to pay $322. The most popular route, (Seattle/Tacoma Intl - Lambert-St Louis), can usually be booked for $161.
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

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Top 7 airlines flying from Seattle to St. Louis

Airline	Cheapest	Average	Flexibility	On-time
Frontier	Cheapest$134	Average$266	FlexibilityNo cancel fee	On-time62%
Delta	Cheapest$182	Average$301	FlexibilityNo cancel fee	On-timeN/A
American Airlines	Cheapest$186	Average$457	FlexibilityNo cancel fee	On-time71%
Southwest	Cheapest$188	Average$420	FlexibilityNo cancel fee	On-time63%
United Airlines	Cheapest$216	Average$379	FlexibilityNo cancel fee	On-time69%
Alaska Airlines	Cheapest$236	Average$417	FlexibilityNo cancel fee	On-time75%
Hawaiian Airlines	Cheapest$249	Average$387	FlexibilityNo cancel fee	On-time85%

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$125+ 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 9/10. Fares are subject to change and may not be available on all flights or dates of travel.

Find cheap flights from Seattle to St. Louis with Cheapflights

1. Tell us where you want to go

2. Select your favorite providers

3. Compare prices and book

Cheapflights Tip: The best prices from Seattle/Tacoma Intl to Lambert-St Louis are usually found in September or October, booked 86 days in advance, depart on a Thursday or Friday and return on a Wednesday

Cheap flight deals from Seattle to St. Louis

Round-trip from

One-way from

Popular in

Cheapest in

Average price

Good round-trip deal

Good one-way deal

Find flight deals from Seattle to St. Louis

Cheapest flights from Seattle to St. LouisExplore 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 July 11, 2025.

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 July 11, 2025.

Cheapflights Fare Finder

Use the filters below to find and compare flights from Seattle to St. Louis that are best for you.

The best insider tips for Seattle to St. Louis flights

Cheapflights partnered with top experts to bring you the best recommendations for your Seattle to St. Louis trip

Airports

SEA

STL

Our travel experts

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.

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 June 27, 2025.

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

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 July 11, 2025.

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 July 6, 2025.

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 July 11, 2025.

Reviews of airlines servicing St. Louis

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.

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?

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

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

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

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

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

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Top 7 airlines flying from Seattle to St. Louis

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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 July 11, 2025.