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$63+ Cheap flights from St. Louis (STL) to Washington

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 1/7. Fares are subject to change and may not be available on all flights or dates of travel.
STL — SEA
Jan 16 — Jan 231
Fri 1/16
Fri 1/23
1 adult, Economy
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Cheap flight deals from St. Louis to Washington

Cheapest flights from St. Louis to Washington
Explore the most affordable flight options available from St. Louis to Washington. Find the lowest fares from popular airlines and budget airlines, with prices last updated on December 17, 2025.

This CheapOair deal was found by Cheapflights users on 12/16. 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 12/1910:10 pmSTL - SEA
1 stop15h 21mFrontier
Thu 1/1512:19 pmSEA - STL
1 stop28h 13mFrontier
Deal found 12/16$268
This CheapOair deal was found by Cheapflights users on 12/15. 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.
Wed 12/247:43 pmSTL - SEA
1 stop18h 47mFrontier
Thu 1/11:25 pmSEA - STL
1 stop18h 37mFrontier
Deal found 12/15$305
This CheapOair deal was found by Cheapflights users on 12/16. 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.
Sun 12/2110:10 pmSTL - SEA
1 stop14h 01mFrontier
Mon 12/296:33 pmSEA - STL
1 stop24h 52mFrontier
Deal found 12/16$339
This Delta deal was found by Cheapflights users on 12/16. 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 12/246:05 amSTL - PDX
1 stop8h 55mDelta
Wed 12/312:11 pmPDX - STL
1 stop6h 05mDelta
Deal found 12/16$344
This CheapOair deal was found by Cheapflights users on 12/15. 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.
Tue 12/2310:10 pmSTL - SEA
1 stop17h 41mFrontier
Sun 1/42:54 pmSEA - STL
1 stop17h 08mFrontier
Deal found 12/15$348
This CheapOair deal was found by Cheapflights users on 12/15. 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.
Mon 12/2210:10 pmSTL - SEA
1 stop14h 01mFrontier
Fri 12/266:33 pmSEA - STL
1 stop24h 52mFrontier
Deal found 12/15$364
This American Airlines deal was found by Cheapflights users on 12/16. 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.
Thu 12/186:05 amSTL - SEA
1 stop8h 32mAmerican Airlines
Thu 1/157:35 amSEA - STL
1 stop6h 39mAmerican Airlines
Deal found 12/16$378
This Super.com deal was found by Cheapflights users on 12/16. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/2310:10 pmSTL - SEA
1 stop17h 41mFrontier
Tue 12/302:54 pmSEA - STL
1 stop17h 08mFrontier
Deal found 12/16$380
This CheapOair deal was found by Cheapflights users on 12/16. 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.
Tue 12/2310:10 pmSTL - SEA
1 stop17h 41mFrontier
Mon 12/296:33 pmSEA - STL
1 stop24h 52mFrontier
Deal found 12/16$384
This CheapOair deal was found by Cheapflights users on 12/15. 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.
Mon 12/2910:10 pmSTL - SEA
1 stop14h 01mFrontier
Thu 1/11:25 pmSEA - STL
1 stop18h 37mFrontier
Deal found 12/15$388
This Delta deal was found by Cheapflights users on 12/16. 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.
Tue 12/237:20 amSTL - SEA
1 stop7h 16mDelta
Tue 12/3010:55 pmSEA - STL
1 stop8h 29mDelta
Deal found 12/16$403
This Alaska Airlines deal was found by Cheapflights users on 12/16. 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.
Thu 12/257:00 amSTL - SEA
Nonstop4h 39mAlaska Airlines
Wed 1/77:55 amSEA - STL
Nonstop3h 59mAlaska Airlines
Deal found 12/16$407

Find flight deals from St. Louis to Washington

Keep the following information in mind while searching for St. Louis to Washington flight deals. Data was last updated December 17, 2025.

Most accurate provider

CheapOair
3 stars

Most trusted provider

CheapOair
3 stars

Round-trip from

$167
(American Airlines)

One-way from

$63
(Trip.com)

Popular in

July

Cheapest in

October

Average price

$354

Good round-trip deal

$303 or less

Good one-way deal

$157 or less
Provider with most accurate pricing for Lambert-St Louis-Seattle/Tacoma Intl flight deals.
Search Deals
Provider most trusted by Cheapflights users for Lambert-St Louis-Seattle/Tacoma Intl flights.
Search Deals
From Lambert-St Louis to Washington
Search Deals
One-way flight from Lambert-St Louis to Washington
Search Deals
Highest demand for flights based on searches. 15% potential increase in price ($60 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease ($10 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in December 2025
Search Deals
Price to beat on a round-trip flight from Lambert-St Louis to Washington.
Search Deals
Price to beat on a one-way flight from Lambert-St Louis to Washington.
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from St. Louis to Washington 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 December 17, 2025.
Use the filters below to find and compare flights from St. Louis to Washington that are best for you.

Fly from

St. Louis

Fly to

Washington

Route

Depart

Return

Price

St. LouisSeattle

STL - SEA

STLSEA

Lambert-St Louis

Sat 2/14

7:00 am-12:25 pm

1 stop7h 25m

Seattle/Tacoma Intl

Wed 2/18

4:40 pm-12:25 am

1 stop5h 45m

$177

St. LouisSeattle

STL - SEA

STLSEA

Lambert-St Louis

Wed 3/11

7:00 am-9:42 am

Nonstop4h 42m

Seattle/Tacoma Intl

Mon 3/16

7:55 am-1:51 pm

Nonstop3h 56m

$207

St. LouisSeattle

STL - SEA

STLSEA

Lambert-St Louis

Fri 3/20

5:29 pm-11:53 pm

1 stop8h 24m

Seattle/Tacoma Intl

Mon 3/23

11:59 pm-8:50 am

1 stop6h 51m

$209

St. LouisSeattle

STL - SEA

STLSEA

Lambert-St Louis

Fri 3/20

5:29 pm-11:53 pm

1 stop8h 24m

Seattle/Tacoma Intl

Thu 3/26

11:59 pm-8:50 am

1 stop6h 51m

$209

St. LouisSeattle

STL - SEA

STLSEA

Lambert-St Louis

Thu 2/26

7:00 am-9:42 am

Nonstop4h 42m

Seattle/Tacoma Intl

Mon 3/2

6:07 pm-11:59 pm

Nonstop3h 52m

$217

St. LouisSeattle

STL - SEA

STLSEA

Lambert-St Louis

Thu 2/12

2:47 pm-5:26 pm

Nonstop4h 39m

Seattle/Tacoma Intl

Mon 2/16

6:07 pm-11:59 pm

Nonstop3h 52m

$217

St. LouisSeattle

STL - SEA

STLSEA

Lambert-St Louis

Mon 1/5

5:26 pm-7:59 pm

Nonstop4h 33m

Seattle/Tacoma Intl

Thu 1/8

7:55 am-1:54 pm

Nonstop3h 59m

$227

St. LouisSeattle

STL - SEA

STLSEA

Lambert-St Louis

Wed 1/21

2:50 pm-5:25 pm

Nonstop4h 35m

Seattle/Tacoma Intl

Fri 1/30

7:55 am-1:54 pm

Nonstop3h 59m

$227

St. LouisSeattle

STL - SEA

STLSEA

Lambert-St Louis

Fri 2/20

6:00 pm-10:59 pm

1 stop6h 59m

Seattle/Tacoma Intl

Tue 2/24

12:55 pm-8:26 pm

1 stop5h 31m

$232

St. LouisSeattle

STL - SEA

STLSEA

Lambert-St Louis

Fri 1/23

9:57 am-6:26 pm

2 stops10h 29m

Seattle/Tacoma Intl

Mon 1/26

12:25 pm-8:58 pm

1 stop6h 33m

$232

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/17

Showing 1-10 of 60 results
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Best time to book a flight from St. Louis to Washington

Have a flexible travel schedule? Discover the best time to fly to Washington from St. Louis 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 St. Louis to Washington

What is the cheapest month to book a flight from St. Louis to State of Washington?

Currently, September is the cheapest month in which you can book a flight from St. Louis to State of Washington (average of $121). Flying from St. Louis to State of Washington in August is currently the most expensive (average of $222). 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 STL to WA?

Find hourly flight availability from St. Louis to Washington. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated December 17, 2025.

Unlike at noon, when flights are generally more expensive, you can save up to 20% on flights from St. Louis to State of Washington by exploring options for tickets in the afternoon.

What is the cheapest day to fly from St. Louis to State of Washington?

Use this chart to determine the cheapest time to fly round-trip from St. Louis to Washington. Price data was last updated on December 16, 2024.

Travelers seeking maximum savings on their St. Louis to State of Washington flight should consider departing on Saturday at noon when fares are most often at their lowest. Sunday afternoons flights should be avoided if possible as fares are typically the most expensive at this time.

Reviews of airlines servicing Washington

Get insights into the airlines that provide service to Washington. 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 Washington. Reviews last updated December 17, 2025.
Read through reviews of airlines operating flights from St. Louis to Washington, such as Alaska Airlines, Southwest, and Delta. 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
11,475 reviews

Crew

8.5

Entertainment

7.0

Boarding

8.1

Comfort

7.8

Overall

8.0

Food

7.1

Reviews

1 / 20
10.0
Excellent

Anonymous,Dec 2025

SJC - SEA

The flight was great. Don’t have to make it better. Everything was OK.
Alaska Airlines
8.0
Very good
11,475 reviews
Alaska Airlines
8.0
Very good
11,475 reviews

Crew

8.5

Entertainment

7.0

Boarding

8.1

Comfort

7.8

Overall

8.0

Food

7.1

Reviews

1 / 20
10.0
Excellent

Anonymous,Dec 2025

SJC - SEA

The flight was great. Don’t have to make it better. Everything was OK.
Southwest
7.9
Good
4,249 reviews
Alaska Airlines
8.0
Very good
11,475 reviews

Crew

8.5

Entertainment

7.0

Boarding

8.1

Comfort

7.8

Overall

8.0

Food

7.1

Reviews

1 / 20
10.0
Excellent

Anonymous,Dec 2025

SJC - SEA

The flight was great. Don’t have to make it better. Everything was OK.
Delta
7.9
Good
8,006 reviews
Alaska Airlines
8.0
Very good
11,475 reviews

Crew

8.5

Entertainment

7.0

Boarding

8.1

Comfort

7.8

Overall

8.0

Food

7.1

Reviews

1 / 20
10.0
Excellent

Anonymous,Dec 2025

SJC - SEA

The flight was great. Don’t have to make it better. Everything was OK.
Hawaiian Airlines
7.8
Good
2,819 reviews
Alaska Airlines
8.0
Very good
11,475 reviews

Crew

8.5

Entertainment

7.0

Boarding

8.1

Comfort

7.8

Overall

8.0

Food

7.1

Reviews

1 / 20
10.0
Excellent

Anonymous,Dec 2025

SJC - SEA

The flight was great. Don’t have to make it better. Everything was OK.
American Airlines
7.2
Good
11,054 reviews
Alaska Airlines
8.0
Very good
11,475 reviews

Crew

8.5

Entertainment

7.0

Boarding

8.1

Comfort

7.8

Overall

8.0

Food

7.1

Reviews

1 / 20
10.0
Excellent

Anonymous,Dec 2025

SJC - SEA

The flight was great. Don’t have to make it better. Everything was OK.

Related info for your journey

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

  • What airport do you fly from for flights from St. Louis to Washington?

    For a flight from St. Louis to Washington, you will be flying from Lambert-St Louis. Lambert-St Louis (STL) is just 12.7 mi from the center of the city.

  • How popular is this St. Louis to State of Washington flight route?

    The Lambert-St Louis to Washington flight path was viewed by 52 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 St. Louis to State of Washington?

    Delta, Alaska Airlines, and United Airlines can get you from St. Louis to State of Washington in just under 4h 42m. Your travel time can differ by up to 3h 15m. St. Louis and State of Washington are separated by a distance of 1704 mi. When browsing for deals, the options you’ll see will be for both nonstop flights and flights with stops.

  • What are the most popular routes from St. Louis to State of Washington?

    When deciding which route to take from St. Louis to State of Washington consider Lambert-St Louis - Seattle/Tacoma Intl, Lambert-St Louis - Portland or Lambert-St Louis - Spokane as they are the most popular.

  • What are the most reliable airlines from St. Louis to State of Washington?

    The top 3 most reliable airlines when flying from St. Louis to State of Washington are Qatar Airways (83%), Japan Airlines (83%) and American Airlines (75%).

  • What are the cheapest flights from St. Louis to State of Washington?

    Looking for the cheapest flight from St. Louis to State of Washington? While on average our users pay $1,258, our data indicates the cheapest price to be $118. The most popular route (Lambert-St Louis - Seattle/Tacoma Intl), is priced around $177.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from St. Louis to Washington 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 St. Louis to State of Washington?

    Currently, September is the cheapest month in which you can book a flight from St. Louis to State of Washington (average of $121). Flying from St. Louis to State of Washington in August is currently the most expensive (average of $222). 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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Alternative routes for St. Louis to Washington

See prices for flight routes from nearby airports that may be better suited for you.
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Top 7 airlines flying from St. Louis to Washington

Discover the top 7 airlines that operate flights from St. Louis to Washington. 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 December 17, 2025.
AirlineCheapestAverageFlexibilityOn-time
DeltaCheapest$94Average$377FlexibilityNo cancel feeOn-timeN/A
FrontierCheapest$120Average$240FlexibilityNo cancel feeOn-time62%
SouthwestCheapest$176Average$432FlexibilityNo cancel feeOn-time63%
American AirlinesCheapest$188Average$402FlexibilityNo cancel feeOn-time71%
United AirlinesCheapest$193Average$416FlexibilityNo cancel feeOn-time69%
Hawaiian AirlinesCheapest$237Average$380FlexibilityNo cancel feeOn-time85%
Alaska AirlinesCheapest$237Average$498FlexibilityNo cancel feeOn-time75%

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