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$99+ 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 5/14. Fares are subject to change and may not be available on all flights or dates of travel.
STL — SEA
Mar 31 — Apr 71
Mon 3/31
Mon 4/7
1 adult, Economy
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Cheap 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 March 26, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$193
(Delta)

One-way from

$99
(Delta)

Popular in

July

Cheapest in

October

Average price

$386

Good round-trip deal

$396 or less

Good one-way deal

$219 or less
Provider with most accurate pricing for Lambert-St Louis-Seattle/Tacoma Intl flight deals.
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Provider most trusted by Cheapflights users for Lambert-St Louis-Seattle/Tacoma Intl flights.
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From Lambert-St Louis to Washington
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One-way flight from Lambert-St Louis to Washington
Search Deals
Highest demand for flights based on searches. 17% potential increase in price ($78 potential increase over avg. RT price).
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Cheapest flight prices on average. 3% potential price decrease ($12 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 Lambert-St Louis to Washington.
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Price to beat on a one-way flight from Lambert-St Louis to Washington.
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Find 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 March 26, 2025.

This Delta deal was found by Cheapflights users on 3/25. 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 4/165:00 pmSTL - SEA
1 stop9h 02mDelta
Sun 4/205:30 amSEA - STL
1 stop5h 58mDelta
Deal found 3/25$193
This Southwest deal was found by Cheapflights users on 3/25. 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.
Sat 6/143:25 pmSTL - SEA
1 stop10h 45mSouthwest
Thu 6/1910:40 pmSEA - STL
1 stop9h 35mSouthwest
Deal found 3/25$194
This American Airlines deal was found by Cheapflights users on 3/25. 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.
Tue 5/135:00 amSTL - SEA
1 stop7h 15mAmerican Airlines
Mon 5/191:10 amSEA - STL
1 stop6h 44mAmerican Airlines
Deal found 3/25$203
This United Airlines deal was found by Cheapflights users on 3/25. 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.
Fri 5/26:11 pmSTL - SEA
1 stop8h 48mUnited Airlines
Mon 5/512:45 pmSEA - STL
1 stop8h 00mUnited Airlines
Deal found 3/25$217
This American Airlines deal was found by Cheapflights users on 3/26. 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.
Mon 4/286:20 pmSTL - PDX
1 stop7h 42mAmerican Airlines
Fri 5/211:52 pmPDX - STL
1 stop7h 30mAmerican Airlines
Deal found 3/26$227
This Delta deal was found by Cheapflights users on 3/25. 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 5/286:05 pmSTL - PDX
1 stop7h 20mDelta
Tue 6/1712:44 amPDX - STL
1 stop7h 50mDelta
Deal found 3/25$233
This Alaska Airlines deal was found by Cheapflights users on 3/25. 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.
Wed 4/236:30 amSTL - SEA
Nonstop4h 24mAlaska Airlines
Tue 4/296:03 pmSEA - STL
Nonstop3h 56mAlaska Airlines
Deal found 3/25$237
This Hawaiian Airlines deal was found by Cheapflights users on 3/25. 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.
Mon 4/216:44 amSTL - SEA
Nonstop4h 30mHawaiian Airlines
Wed 4/236:03 pmSEA - STL
Nonstop3h 56mHawaiian Airlines
Deal found 3/25$257
This Sun Country Air deal was found by Cheapflights users on 3/25. 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 Sun Country Air is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 4/66:35 amSTL - SEA
1 stop18h 16mSun Country Air
Sun 4/138:30 amSEA - STL
1 stop9h 08mSun Country Air
Deal found 3/25$275
This Expedia deal was found by Cheapflights users on 3/26. 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.
Mon 5/126:53 pmSTL - SEA
1 stop7h 51mMultiple Airlines
Fri 5/166:04 pmSEA - STL
Nonstop4h 00mMultiple Airlines
Deal found 3/26$279
This CheapOair deal was found by Cheapflights users on 3/25. 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 4/26:51 pmSTL - PDX
1 stop7h 46mFrontier
Fri 4/46:40 amPDX - STL
1 stop24h 26mFrontier
Deal found 3/25$280
This CheapOair deal was found by Cheapflights users on 3/25. 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 4/76:38 pmSTL - SEA
1 stop16h 57mFrontier
Fri 4/111:56 pmSEA - STL
1 stop17h 10mFrontier
Deal found 3/25$280

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 March 26, 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

Wed 4/16

5:00 pm-12:02 am

1 stop9h 02m

Seattle/Tacoma Intl

Sun 4/20

5:30 am-1:28 pm

1 stop5h 58m

$193

St. LouisSeattle

STL - SEA

STLSEA

Lambert-St Louis

Sat 6/14

3:25 pm-12:10 am

1 stop10h 45m

Seattle/Tacoma Intl

Thu 6/19

10:40 pm-10:15 am

1 stop9h 35m

$194

St. LouisSeattle

STL - SEA

STLSEA

Lambert-St Louis

Tue 5/13

5:00 am-10:15 am

1 stop7h 15m

Seattle/Tacoma Intl

Mon 5/19

1:10 am-9:54 am

1 stop6h 44m

$203

St. LouisSeattle

STL - SEA

STLSEA

Lambert-St Louis

Fri 5/2

6:11 pm-12:59 am

1 stop8h 48m

Seattle/Tacoma Intl

Mon 5/5

12:45 pm-10:45 pm

1 stop8h 00m

$217

St. LouisPortland

STL - PDX

STLPDX

Lambert-St Louis

Mon 4/28

6:20 pm-12:02 am

1 stop7h 42m

Portland

Fri 5/2

11:52 pm-9:22 am

1 stop7h 30m

$227

St. LouisPortland

STL - PDX

STLPDX

Lambert-St Louis

Wed 5/28

6:05 pm-11:25 pm

1 stop7h 20m

Portland

Tue 6/17

12:44 am-10:34 am

1 stop7h 50m

$233

St. LouisSeattle

STL - SEA

STLSEA

Lambert-St Louis

Wed 4/23

6:30 am-8:54 am

Nonstop4h 24m

Seattle/Tacoma Intl

Tue 4/29

6:03 pm-11:59 pm

Nonstop3h 56m

$237

St. LouisSeattle

STL - SEA

STLSEA

Lambert-St Louis

Mon 4/21

6:44 am-9:14 am

Nonstop4h 30m

Seattle/Tacoma Intl

Wed 4/23

6:03 pm-11:59 pm

Nonstop3h 56m

$257

St. LouisSeattle

STL - SEA

STLSEA

Lambert-St Louis

Sun 4/6

6:35 am-10:51 pm

1 stop18h 16m

Seattle/Tacoma Intl

Sun 4/13

8:30 am-7:38 pm

1 stop9h 08m

$275

St. LouisSeattle

STL - SEA

STLSEA

Lambert-St Louis

Mon 5/12

6:53 pm-12:44 am

1 stop7h 51m

Seattle/Tacoma Intl

Fri 5/16

6:04 pm-12:04 am

Nonstop4h 00m

$279

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/26

Showing 1-10 of 52 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, January is the cheapest month in which you can book a flight from St. Louis to State of Washington (average of $238). Flying from St. Louis to State of Washington in July is currently the most expensive (average of $411). 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 March 26, 2025.

When flying from St. Louis to State of Washington, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.

Weekly flight availability from St. Louis to State of Washington

Explore weekly flight availability from St. Louis to Washington. 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 26, 2025.

The most flights from STL to USWA are scheduled on a Monday (12 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (2 on average).

Rainfall in Washington by month

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

In terms of precipitation, rainfall in State of Washington ranges from 0.7 - 6.6 inches per month. November is typically the wettest month, when rainfall can reach 6.6 in. July is typically the driest time to visit State of Washington when rainfall is around 0.7 in.

Temperature in Washington by month

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

If weather is an important factor for your trip to State of Washington, 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 66.2 F. Travelers looking to avoid the cold should look outside of December, when temperatures are typically at their lowest (around 41.0 F).

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 March 26, 2025.
Get a feel of what it's like to fly with Southwest, Alaska Airlines and Delta from St. Louis to Washington by reading reviews from past customers. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.1
Very good
4,273 reviews

Overall

8.1

Boarding

8.2

Comfort

8.1

Entertainment

7.6

Food

7.1

Crew

8.6

Reviews

1 / 20
8.0
Excellent

Ila,Mar 2025

HOU - DAL

Our original flight was delayed. We were able to change our flight and got home at close to the same time. Looking forward to when you have assigned seating.
Southwest
8.1
Very good
4,273 reviews
Southwest
8.1
Very good
4,273 reviews

Overall

8.1

Boarding

8.2

Comfort

8.1

Entertainment

7.6

Food

7.1

Crew

8.6

Reviews

1 / 20
8.0
Excellent

Ila,Mar 2025

HOU - DAL

Our original flight was delayed. We were able to change our flight and got home at close to the same time. Looking forward to when you have assigned seating.
Alaska Airlines
8.0
Very good
9,789 reviews
Southwest
8.1
Very good
4,273 reviews

Overall

8.1

Boarding

8.2

Comfort

8.1

Entertainment

7.6

Food

7.1

Crew

8.6

Reviews

1 / 20
8.0
Excellent

Ila,Mar 2025

HOU - DAL

Our original flight was delayed. We were able to change our flight and got home at close to the same time. Looking forward to when you have assigned seating.
Delta
8.0
Very good
7,891 reviews
Southwest
8.1
Very good
4,273 reviews

Overall

8.1

Boarding

8.2

Comfort

8.1

Entertainment

7.6

Food

7.1

Crew

8.6

Reviews

1 / 20
8.0
Excellent

Ila,Mar 2025

HOU - DAL

Our original flight was delayed. We were able to change our flight and got home at close to the same time. Looking forward to when you have assigned seating.
Hawaiian Airlines
7.9
Good
2,331 reviews
Southwest
8.1
Very good
4,273 reviews

Overall

8.1

Boarding

8.2

Comfort

8.1

Entertainment

7.6

Food

7.1

Crew

8.6

Reviews

1 / 20
8.0
Excellent

Ila,Mar 2025

HOU - DAL

Our original flight was delayed. We were able to change our flight and got home at close to the same time. Looking forward to when you have assigned seating.
United Airlines
7.4
Good
8,608 reviews
Southwest
8.1
Very good
4,273 reviews

Overall

8.1

Boarding

8.2

Comfort

8.1

Entertainment

7.6

Food

7.1

Crew

8.6

Reviews

1 / 20
8.0
Excellent

Ila,Mar 2025

HOU - DAL

Our original flight was delayed. We were able to change our flight and got home at close to the same time. Looking forward to when you have assigned seating.

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 43 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 to fly from St. Louis to State of Washington one-way?

    To fly one-way, consider booking your trip with Delta, which is currently one of the cheapest options available, starting at $99. Southwest flights start at $100 while deals on United Airlines start at $109 one-way.

  • 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 (90%), Hawaiian Airlines (89%) and American Airlines (86%).

  • 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 $1,315, our data indicates the cheapest price to be $144. 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, January is the cheapest month in which you can book a flight from St. Louis to State of Washington (average of $238). Flying from St. Louis to State of Washington in July is currently the most expensive (average of $411). 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.

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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 March 26, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$118Average$191FlexibilityNo cancel feeOn-time62%
DeltaCheapest$170Average$391FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$208Average$420FlexibilityNo cancel feeOn-time71%
United AirlinesCheapest$216Average$422FlexibilityNo cancel feeOn-time69%
Alaska AirlinesCheapest$236Average$534FlexibilityNo cancel feeOn-time75%
Hawaiian AirlinesCheapest$237Average$424FlexibilityNo cancel feeOn-time85%
SouthwestCheapest$344Average$474FlexibilityNo cancel feeOn-time63%
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