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$70+ Cheap flights from Washington, D.C. (WAS) to St. Louis (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 4/8. Fares are subject to change and may not be available on all flights or dates of travel.
WAS — STL
Apr 22 — Apr 291
Wed 4/22
Wed 4/29
1 adult, Economy
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Find cheap flights from Washington, D.C. to St. Louis with Cheapflights

1. Tell us where you want to go

Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”

2. Select your favorite providers

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3. Compare prices and book

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Cheapflights Tip: The best prices from Washington, D.C. to Lambert-St Louis are usually found in August or October, booked 83 days in advance, depart on a Tuesday or Saturday and return on a Friday

Cheap flight deals from Washington, D.C. to St. Louis

Cheapest flights from Washington, D.C. to St. Louis
Explore the most affordable flight options available from Washington, D.C. to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on March 23, 2026.

This Frontier deal was found by Cheapflights users on 3/19. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/101:04 pm
BWI
-
STL
1 stop11h 54m
Frontier
Wed 4/158:23 pm
STL
-
BWI
1 stop10h 39m
Frontier
Deal found 3/19$140
This CheapOair deal was found by Cheapflights users on 3/21. 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 4/1212:08 pm
BWI
-
STL
1 stop20h 43m
Frontier
Wed 4/158:23 pm
STL
-
BWI
1 stop10h 39m
Frontier
Deal found 3/21$151
This Kiwi.com deal was found by Cheapflights users on 3/18. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/225:49 pm
BWI
-
STL
1 stop17h 41m
Frontier
Tue 5/196:33 pm
STL
-
BWI
1 stop12h 10m
Frontier
Deal found 3/18$154
This Kiwi.com deal was found by Cheapflights users on 3/19. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/59:25 pm
BWI
-
STL
1 stop12h 30m
Frontier
Tue 5/126:33 pm
STL
-
BWI
1 stop12h 10m
Frontier
Deal found 3/19$157
This Expedia deal was found by Cheapflights users on 3/21. 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 4/82:27 pm
BWI
-
STL
1 stop9h 58m
Frontier
Wed 4/158:23 pm
STL
-
BWI
1 stop10h 39m
Frontier
Deal found 3/21$160
This Kiwi.com deal was found by Cheapflights users on 3/19. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/215:49 pm
BWI
-
STL
1 stop14h 01m
Frontier
Wed 4/228:23 pm
STL
-
BWI
1 stop10h 39m
Frontier
Deal found 3/19$162
This Mytrip deal was found by Cheapflights users on 3/20. 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 4/131:04 pm
BWI
-
STL
1 stop11h 21m
Frontier
Thu 4/1611:25 am
STL
-
BWI
1 stop4h 48m
Frontier
Deal found 3/20$166
This Kiwi.com deal was found by Cheapflights users on 3/19. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/59:25 pm
BWI
-
STL
1 stop12h 30m
Frontier
Mon 5/115:27 pm
STL
-
BWI
1 stop13h 16m
Frontier
Deal found 3/19$169
This CheapOair deal was found by Cheapflights users on 3/19. 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 4/108:58 am
BWI
-
STL
1 stop16h 00m
Frontier
Fri 4/244:59 pm
STL
-
BWI
1 stop26h 52m
Frontier
Deal found 3/19$171
This Kiwi.com deal was found by Cheapflights users on 3/19. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/225:49 pm
BWI
-
STL
1 stop17h 41m
Frontier
Wed 5/135:27 pm
STL
-
BWI
1 stop13h 16m
Frontier
Deal found 3/19$174
This Kiwi.com deal was found by Cheapflights users on 3/19. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/89:25 pm
BWI
-
STL
1 stop12h 30m
Frontier
Mon 5/115:27 pm
STL
-
BWI
1 stop13h 16m
Frontier
Deal found 3/19$178
This Frontier deal was found by Cheapflights users on 3/20. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/72:27 pm
BWI
-
STL
1 stop9h 58m
Frontier
Thu 4/96:29 pm
STL
-
BWI
1 stop5h 15m
Frontier
Deal found 3/20$180

Find flight deals from Washington, D.C. to St. Louis

Discover tips and strategies to find the most affordable flight options for your journey from Washington, D.C. (WAS) 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 23, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$140
(Frontier)

One-way from

$70
(Kiwi.com)

Popular in

March

Cheapest in

August

Average price

$399

Good round-trip deal

$311 or less

Good one-way deal

$174 or less
Provider with most accurate pricing for Washington, D.C. (WAS)-Lambert-St Louis flight deals.
Search Deals
Provider most trusted by Cheapflights users for Washington, D.C. (WAS)-Lambert-St Louis flights.
Search Deals
From Washington, D.C. (WAS) to Lambert-St Louis
Search Deals
One-way flight from Washington, D.C. (WAS) to Lambert-St Louis
Search Deals
Highest demand for flights based on searches. 8% potential increase in price ($29 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease ($7 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in March 2026
Search Deals
Price to beat on a round-trip flight from Washington, D.C. (WAS) to Lambert-St Louis.
Search Deals
Price to beat on a one-way flight from Washington, D.C. (WAS) to Lambert-St Louis.
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Washington, D.C. 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 23, 2026.
Use the filters below to find and compare flights from Washington, D.C. to St. Louis that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

BaltimoreSt. Louis

BWI - STL

BWISTL

Baltimore/Washington

Mon 4/20

6:05 am-10:15 am

1 stop5h 10m

Lambert-St Louis

Sat 4/25

5:40 am-11:55 am

1 stop5h 15m

$276

Washington, D.C.St. Louis

DCA - STL

DCASTL

Washington, D.C. Reagan-National

Mon 4/20

2:45 pm-4:05 pm

Nonstop2h 20m

Lambert-St Louis

Sat 4/25

3:25 pm-6:25 pm

Nonstop2h 00m

$277

Washington, D.C.St. Louis

DCA - STL

DCASTL

Washington, D.C. Reagan-National

Thu 6/11

8:00 am-9:10 am

Nonstop2h 10m

Lambert-St Louis

Mon 6/15

5:05 am-1:10 pm

1 stop7h 05m

$290

Washington, D.C.St. Louis

DCA - STL

DCASTL

Washington, D.C. Reagan-National

Sat 4/25

6:25 pm-7:50 pm

Nonstop2h 25m

Lambert-St Louis

Tue 4/28

8:05 am-11:05 am

Nonstop2h 00m

$295

Washington, D.C.St. Louis

DCA - STL

DCASTL

Washington, D.C. Reagan-National

Mon 4/20

8:00 am-9:20 am

Nonstop2h 20m

Lambert-St Louis

Fri 4/24

7:40 pm-10:40 pm

Nonstop2h 00m

$301

Washington, D.C.St. Louis

DCA - STL

DCASTL

Washington, D.C. Reagan-National

Sun 5/31

6:05 am-9:30 am

1 stop4h 25m

Lambert-St Louis

Wed 6/10

3:30 pm-10:40 pm

1 stop6h 10m

$307

BaltimoreSt. Louis

BWI - STL

BWISTL

Baltimore/Washington

Mon 5/4

6:00 pm-8:55 pm

1 stop3h 55m

Lambert-St Louis

Thu 5/7

4:00 pm-7:05 pm

Nonstop2h 05m

$309

Washington, D.C.St. Louis

IAD - STL

IADSTL

Washington, D.C. Dulles Intl

Sat 4/25

5:50 am-1:20 pm

1 stop8h 30m

Lambert-St Louis

Tue 4/28

8:35 am-4:50 pm

1 stop7h 15m

$315

Washington, D.C.St. Louis

DCA - STL

DCASTL

Washington, D.C. Reagan-National

Sun 4/26

6:05 am-9:30 am

1 stop4h 25m

Lambert-St Louis

Tue 4/28

1:10 pm-4:10 pm

Nonstop2h 00m

$315
Quickest round-trip

Washington, D.C.St. Louis

DCA - STL

DCASTL

Washington, D.C. Reagan-National

Sat 6/13

8:00 am-9:10 am

Nonstop2h 10m

Lambert-St Louis

Mon 6/15

7:55 pm-10:55 pm

Nonstop2h 00m

$315

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/18

Showing 1-10 of 60 resultsSorted by cheapest first
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Compare providers for flights from Washington, D.C. 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 Washington, D.C. to St. Louis in March.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
JustAirTicketPrice Accuracy-Trust Score*1 star

*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 Washington, D.C.-St. Louis flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Washington, D.C.-St. Louis flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Washington, D.C.-St. Louis flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Washington, D.C.-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 Washington, D.C.-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 Washington, D.C. to St. Louis

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

How far ahead should I book a flight from Washington, D.C. to St. Louis?

Use this chart to determine the optimal time to book a round-trip flight from Washington, D.C. to St. Louis. Price data was last updated on March 13, 2026.

To ensure you get the cheapest price possible for a flight from Washington, D.C. to St. Louis, you should look to book at least 83 days in advance of your intended travel date. The price of your flight may increase if you delay and leave booking until a week or so before departure.

What is the cheapest month to book a flight from Washington, D.C. to St. Louis?

Currently, September is the cheapest month in which you can book a flight from Washington, D.C. to St. Louis (average of $109). Flying from Washington, D.C. to St. Louis in February is currently the most expensive (average of $230). 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 WAS to STL?

Find hourly flight availability from Washington, D.C. 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 23, 2026.

It’s optimal to fly from Washington, D.C. to St. Louis in the evening. By choosing this option you can save up to 25% on the cost of your flight, compared to a flight in the afternoon.

What is the cheapest day to fly from Washington, D.C. to St. Louis?

Use this chart to determine the cheapest time to fly round-trip from Washington, D.C. to St. Louis. Price data was last updated on March 23, 2026.

Travelers seeking maximum savings on their Washington, D.C. to St. Louis flight should consider departing on Friday evenings when fares are most often at their lowest. Sunday evenings flights should be avoided if possible as fares are typically the most expensive at this time.

Weekly flight availability from Washington, D.C. to St. Louis

Explore weekly flight availability from Washington, D.C. 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 23, 2026.

The most flights from WAS to STL are scheduled on a Monday (15 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (10 on average).

How much does it cost to fly round-trip from Washington, D.C. to St. Louis?

The best insider tips for Washington, D.C. to St. Louis flights

AI-powered summary based on content written by travel experts. AI can make mistakes.
Cheapflights partnered with top experts to bring you the best recommendations for your Washington, D.C. to St. Louis trip
Our travel experts
Emily Zemler

Emily Zemler

Expert on DCA

Emily is a freelance writer and book author based in London covering entertainment and travel. Her work has appeared in Los Angeles Times, Observer, and Conde Nast Traveler She has ventured to more than 40 countries and all seven continents, always in search of a great art museum. She has written extensively about hotels, luxury travel, and aviation.

Read more
Taryn White

Taryn White

Expert on STL

Taryn White is a freelance travel writer, digital creator, and travel advisor who has visited nearly 100 countries and all 50 states. She’s familiar with many airports and enjoys beach hopping, boutique hotels, spa experiences, and exploring local culture. Her work has appeared in Travel + Leisure, Condé Nast Traveler, National Geographic, Smithsonian Magazine, AFAR, and more.

Read more
Ramsey Qubein

Ramsey Qubein

Expert on IAD

An avid traveler and aviation expert who has visited 173 countries, all 50 states and seven continents, Ramsey Qubein flies nearly 400,000 miles a year. As a North Carolina-based freelance journalist for publications including Conde Nast Traveler, Forbes, USA Today and Bloomberg among others, he explores the latest trends in aviation, hospitality, cruises and business.

Read more

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 23, 2026.
See what other customers who have flown with Southwest,Delta, andUnited Airlines from Washington, D.C. to St. Louis have to say. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.0
Very good
4,324 reviews

Overall

8.0

Boarding

8.1

Entertainment

7.5

Food

7.0

Comfort

8.0

Crew

8.6

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.
Southwest
8.0
Very good
4,324 reviews
Southwest
8.0
Very good
4,324 reviews

Overall

8.0

Boarding

8.1

Entertainment

7.5

Food

7.0

Comfort

8.0

Crew

8.6

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.
Delta
7.9
Good
8,319 reviews
Southwest
8.0
Very good
4,324 reviews

Overall

8.0

Boarding

8.1

Entertainment

7.5

Food

7.0

Comfort

8.0

Crew

8.6

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.
United Airlines
7.4
Good
9,462 reviews
Southwest
8.0
Very good
4,324 reviews

Overall

8.0

Boarding

8.1

Entertainment

7.5

Food

7.0

Comfort

8.0

Crew

8.6

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.
American Airlines
7.1
Good
11,489 reviews
Southwest
8.0
Very good
4,324 reviews

Overall

8.0

Boarding

8.1

Entertainment

7.5

Food

7.0

Comfort

8.0

Crew

8.6

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.
Frontier
5.7
Fair
3,019 reviews
Southwest
8.0
Very good
4,324 reviews

Overall

8.0

Boarding

8.1

Entertainment

7.5

Food

7.0

Comfort

8.0

Crew

8.6

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.

Related info for your journey

Find useful and relevant information for your journey from Washington, D.C. 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 airport do you fly into for flights to St. Louis from Washington, D.C.?

    Lambert-St Louis (STL), located 12.7 mi from the city center, is the airport you fly into when you book flights from Washington, D.C. to St. Louis. 5 airlines have flights to Lambert-St Louis from Washington, D.C. on a regular basis. Booking flights from Washington, D.C. to Lambert-St Louis should not be difficult; the airport handles an average of 13 inbound flights from Washington, D.C. per day.

  • How long is the flight from Washington, D.C. to St. Louis?

    A quick flight from Washington, D.C. to St. Louis can take about 5h 10m. Southwest provides one of the quickest options available for as low as $276. There are 736 mi between Washington, D.C. and St. Louis. When browsing for deals, the options you’ll see will be for both nonstop flights and flights with stops.

  • What are the cheapest airlines flying from Washington, D.C. to St. Louis round-trip?

    Our cheapest airline available from Washington, D.C. to St. Louis is Frontier. Our recent data shows that you can find tickets from as low as $78 on this airline. Additional options worth looking into are Delta and American Airlines, starting at $124 and $167 round-trip. These flights start at 76% lower than the current average price 3 months from now.

  • What are the cheapest airlines to fly from Washington, D.C. to St. Louis one-way?

    To fly one-way, consider booking your trip with Frontier, which is currently one of the cheapest options available, starting at $60. Southwest flights start at $95 while deals on Delta start at $99 one-way.

  • What are the most popular routes from Washington, D.C. to St. Louis?

    When deciding which route to take from Washington, D.C. to St. Louis consider Washington, D.C. Dulles Intl - Lambert-St Louis, Baltimore/Washington - Lambert-St Louis or Washington, D.C. Reagan-National - Lambert-St Louis as they are the most popular.

  • What are the most reliable airlines from Washington, D.C. 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 Washington, D.C. to St. Louis on time: Republic Airways (100%), United Airlines (84%), Lufthansa (77%).

  • What are the cheapest flights from Washington, D.C. to St. Louis?

    The cheapest flight price from Washington, D.C. to St. Louis is $127. On average you can expect to pay $630. The most popular route, (Washington, D.C. Dulles Intl - Lambert-St Louis), can usually be booked for $204.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from Washington, D.C. 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 Washington, D.C. to St. Louis?

    Currently, September is the cheapest month in which you can book a flight from Washington, D.C. to St. Louis (average of $109). Flying from Washington, D.C. to St. Louis in February is currently the most expensive (average of $230). 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 St. Louis?

Book flights to St. Louis if you plan to visit one of these locations
Edwardsville
O'Fallon
Fenton
Swansea
Fairview Heights
Maryland Heights
Collinsville
Eureka
Wentzville
Glencoe
Chesterfield
Alton
Farmington
Festus

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Top 5 airlines flying from Washington, D.C. to St. Louis

Discover the top 5 airlines that operate flights from Washington, D.C. 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 23, 2026.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$78Average$197FlexibilityNo cancel feeOn-time62%
DeltaCheapest$124Average$280FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$167Average$334FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$188Average$368FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$257Average$496FlexibilityNo cancel feeOn-time69%

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