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Washington, D.C.

$70+ Cheap flights from St. Louis (STL) to Washington, D.C. (WAS)

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 5/6. Fares are subject to change and may not be available on all flights or dates of travel.
STL — WAS
Apr 22 — Apr 291
Wed 4/22
Wed 4/29
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 Lambert-St Louis to Washington, D.C. are usually found in August or October, booked 62 days in advance, depart on a Friday or Tuesday and return on a Tuesday

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

Cheapest flights from St. Louis to Washington, D.C.
Explore the most affordable flight options available from St. Louis to Washington, D.C.. 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 3/23. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/158:23 pm
STL
-
BWI
1 stop10h 39m
Frontier
Sat 4/185:45 pm
BWI
-
STL
1 stop6h 34m
Frontier
Deal found 3/23$140
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.
Wed 4/158:23 pm
STL
-
BWI
1 stop10h 39m
Frontier
Tue 4/215:35 pm
BWI
-
STL
1 stop6h 44m
Frontier
Deal found 3/20$160
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.
Mon 5/48:23 pm
STL
-
BWI
1 stop10h 20m
Frontier
Wed 5/69:25 pm
BWI
-
STL
1 stop20h 29m
Frontier
Deal found 3/18$169
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.
Thu 4/26:29 pm
STL
-
BWI
1 stop5h 15m
Frontier
Sun 4/56:05 am
BWI
-
STL
1 stop5h 25m
Frontier
Deal found 3/19$180
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.
Thu 4/96:29 pm
STL
-
BWI
1 stop5h 15m
Frontier
Sat 4/115:42 pm
BWI
-
STL
1 stop6h 43m
Frontier
Deal found 3/20$181
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.
Thu 4/1611:25 am
STL
-
BWI
1 stop12h 19m
Frontier
Tue 4/2112:17 pm
BWI
-
STL
1 stop19h 33m
Frontier
Deal found 3/18$196
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.
Fri 4/178:23 pm
STL
-
BWI
1 stop13h 58m
Frontier
Tue 4/2112:17 pm
BWI
-
STL
1 stop19h 33m
Frontier
Deal found 3/18$202
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/248:23 pm
STL
-
BWI
1 stop13h 58m
Frontier
Sun 4/268:57 am
BWI
-
STL
1 stop22h 53m
Frontier
Deal found 3/21$203
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.
Thu 4/26:29 pm
STL
-
BWI
1 stop5h 15m
Frontier
Tue 4/72:27 pm
BWI
-
STL
1 stop9h 58m
Frontier
Deal found 3/20$205
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/228:23 pm
STL
-
BWI
1 stop10h 39m
Frontier
Wed 4/295:49 pm
BWI
-
STL
2 stops30h 30m
Frontier
Deal found 3/21$209
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/146:55 pm
STL
-
BWI
1 stop11h 48m
Frontier
Mon 5/189:25 pm
BWI
-
STL
1 stop21h 08m
Frontier
Deal found 3/20$212
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.
Thu 4/26:29 pm
STL
-
IAD
1 stop5h 07m
Frontier
Mon 4/68:30 pm
IAD
-
STL
1 stop27h 55m
Frontier
Deal found 3/21$240

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

Discover tips and strategies to find the most affordable flight options for your journey from St. Louis (STL) to Washington, D.C. (WAS). 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
(Frontier)

Popular in

March

Cheapest in

August

Average price

$372

Good round-trip deal

$304 or less

Good one-way deal

$175 or less
Provider with most accurate pricing for Lambert-St Louis-Washington, D.C. (WAS) flight deals.
Search Deals
Provider most trusted by Cheapflights users for Lambert-St Louis-Washington, D.C. (WAS) flights.
Search Deals
From Lambert-St Louis to Washington, D.C. (WAS)
Search Deals
One-way flight from Lambert-St Louis to Washington, D.C. (WAS)
Search Deals
Highest demand for flights based on searches. 12% potential increase in price ($44 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease ($6 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 Lambert-St Louis to Washington, D.C. (WAS).
Search Deals
Price to beat on a one-way flight from Lambert-St Louis to Washington, D.C. (WAS).
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from St. Louis to Washington, D.C. 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 St. Louis to Washington, D.C. that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

St. LouisWashington, D.C.

STL - DCA

STLDCA

Lambert-St Louis

Thu 5/14

7:40 pm-10:40 pm

Nonstop2h 00m

Washington, D.C. Reagan-National

Tue 5/26

2:40 pm-4:00 pm

Nonstop2h 20m

$251

St. LouisWashington, D.C.

STL - DCA

STLDCA

Lambert-St Louis

Mon 5/4

7:40 pm-10:40 pm

Nonstop2h 00m

Washington, D.C. Reagan-National

Wed 5/6

11:40 am-6:00 pm

2 stops7h 20m

$266

St. LouisWashington, D.C.

STL - DCA

STLDCA

Lambert-St Louis

Wed 5/13

10:25 am-4:15 pm

1 stop4h 50m

Washington, D.C. Reagan-National

Fri 5/15

6:35 pm-11:55 pm

1 stop6h 20m

$274

St. LouisWashington, D.C.

STL - IAD

STLIAD

Lambert-St Louis

Mon 4/27

5:59 pm-11:03 pm

1 stop4h 04m

Washington, D.C. Dulles Intl

Thu 4/30

6:00 am-9:42 am

1 stop4h 42m

$285
Quickest round-trip

St. LouisWashington, D.C.

STL - DCA

STLDCA

Lambert-St Louis

Tue 6/16

3:55 pm-6:55 pm

Nonstop2h 00m

Washington, D.C. Reagan-National

Tue 6/23

3:00 pm-4:15 pm

Nonstop2h 15m

$315

St. LouisWashington, D.C.

STL - DCA

STLDCA

Lambert-St Louis

Thu 5/7

10:15 am-6:05 pm

2 stops6h 50m

Washington, D.C. Reagan-National

Sat 5/9

8:00 am-9:20 am

Nonstop2h 20m

$320

St. LouisWashington, D.C.

STL - DCA

STLDCA

Lambert-St Louis

Sat 4/11

6:10 am-4:15 pm

2 stops9h 05m

Washington, D.C. Reagan-National

Mon 4/13

3:35 pm-6:40 pm

1 stop4h 05m

$321

St. LouisWashington, D.C.

STL - IAD

STLIAD

Lambert-St Louis

Thu 5/7

1:27 pm-9:24 pm

1 stop6h 57m

Washington, D.C. Dulles Intl

Mon 5/11

7:38 pm-11:59 pm

1 stop5h 21m

$322

St. LouisWashington, D.C.

STL - DCA

STLDCA

Lambert-St Louis

Sun 4/26

7:20 pm-10:20 pm

Nonstop2h 00m

Washington, D.C. Reagan-National

Thu 4/30

8:00 am-9:20 am

Nonstop2h 20m

$323

St. LouisWashington, D.C.

STL - IAD

STLIAD

Lambert-St Louis

Tue 6/16

8:35 am-11:47 am

Nonstop2h 12m

Washington, D.C. Dulles Intl

Tue 6/23

5:42 pm-11:36 pm

1 stop6h 54m

$325

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/23

Showing 1-10 of 60 resultsSorted by cheapest first
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Compare providers for flights from St. Louis to Washington, D.C.

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 St. Louis to Washington, D.C. in March.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust 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 St. Louis-Washington, D.C. flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on St. Louis-Washington, D.C. flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from St. Louis-Washington, D.C. flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on St. Louis-Washington, D.C. 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 St. Louis-Washington, D.C. 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 St. Louis to Washington, D.C.

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

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

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

Booking 62 days in advance of your planned departure date is, on average, the best time to get cheap flights from St. Louis to Washington, D.C.. The general trend is that the closer you book to the departure date, the more expensive your flight will be.

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

Currently, December is the cheapest month in which you can book a flight from St. Louis to Washington, D.C. (average of $98). Flying from St. Louis to Washington, D.C. in March is currently the most expensive (average of $201). 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 WAS?

Find hourly flight availability from St. Louis to Washington, D.C.. 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 typically best to fly out from St. Louis to Washington, D.C. in the afternoon. Doing so could potentially save you 41% on the flight price compared to flying at noon, which is usually more expensive.

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

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

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

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

Explore weekly flight availability from St. Louis to Washington, D.C.. 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 STL to WAS are scheduled on a Monday (14 on average). You will have fewer flight options on Tuesday, which is when the least amount of flights are scheduled (10 on average).

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

What’s the top layover airport for flights from St. Louis to Washington, D.C.?

Share of 1-stop round-trip flights from St. Louis to Washington, D.C. chosen by Cheapflights users in the past 12 months, using the same layover each way.

Chicago (ORD) – chosen by Cheapflights users on 50% of 1-stop itineraries from St. Louis to Washington, D.C. on Cheapflights.

What’s the cheapest layover airport for flights from St. Louis to Washington, D.C.?

Average round-trip fare for 1-stop flights from St. Louis to Washington, D.C., chosen by Cheapflights users in the past 12 months, with the same layover each way.

Denver (DEN) is the most affordable 1-stop option, with an average round-trip price of $294.

What’s the fastest layover option from St. Louis to Washington, D.C.?

Shortest average travel time for 1-stop one-way flights from St. Louis to Washington, D.C., based on itineraries clicked by Cheapflights users over the past 12 months, grouped by layover airport.

Flights via Chicago (ORD) have the shortest average one-way travel time for 1-stop routes: 4h 56m.

Which airport typically offers the quickest layover for flights from St. Louis to Washington, D.C.?

Average layover duration for 1-stop one-way flights from St. Louis to Washington, D.C., chosen by Cheapflights users in the last 12 months, grouped by stopover airport.

Flights via Chicago (ORD) offer the fastest connection on this route, with an average layover time of 1h 28m.

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

Get insights into the airlines that provide service to Washington, D.C.. 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, D.C.. Reviews last updated March 23, 2026.
Get a feel of what it's like to fly with Southwest,Delta, andAmerican Airlines from St. Louis to Washington, D.C. by reading reviews from past customers. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.0
Very good
4,324 reviews

Boarding

8.1

Crew

8.6

Entertainment

7.5

Overall

8.0

Food

7.0

Comfort

8.0

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

Boarding

8.1

Crew

8.6

Entertainment

7.5

Overall

8.0

Food

7.0

Comfort

8.0

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
8,318 reviews
Southwest
8.0
Very good
4,324 reviews

Boarding

8.1

Crew

8.6

Entertainment

7.5

Overall

8.0

Food

7.0

Comfort

8.0

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
11,486 reviews
Southwest
8.0
Very good
4,324 reviews

Boarding

8.1

Crew

8.6

Entertainment

7.5

Overall

8.0

Food

7.0

Comfort

8.0

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
3,020 reviews
Southwest
8.0
Very good
4,324 reviews

Boarding

8.1

Crew

8.6

Entertainment

7.5

Overall

8.0

Food

7.0

Comfort

8.0

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 St. Louis to Washington, D.C.. 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, D.C.?

    If you book a flight to Washington, D.C. from St. Louis, you will be flying from Lambert-St Louis, which is the city’s only airport. Lambert-St Louis (STL) is located 12.7 mi from the center of St. Louis. There are 12 flights from Lambert-St Louis to Washington, D.C. per day from 5 different airlines.

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

    There are many flights that can get you from St. Louis to Washington, D.C. in 2h. Fly via Southwest, Delta, or United Airlines to get the fastest option. There are 717 mi between St. Louis and Washington, D.C.. Both multi-stop and nonstop flights can be found to your destination and back.

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

    Flying on Delta is currently your cheapest option to Washington, D.C., with prices starting at $99. Additional round-trip tickets that might be worth considering are offered by Frontier and American Airlines, with the lowest prices starting at $113 and $156, respectively. Delta is 67% cheaper than the average price of flights available within the next 90 days to this destination.

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

    For one-way options, check prices for American Airlines. According to our data, you can fly for as low as $67. Users have also found prices from $72 and $89 on Frontier and Southwest, respectively.

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

    The most popular route from St. Louis to Washington, D.C. is Lambert-St Louis - Washington, D.C. Dulles Intl. You may also consider Lambert-St Louis - Baltimore/Washington or Lambert-St Louis - Washington, D.C. Reagan-National.

  • What are the most reliable airlines from St. Louis to Washington, D.C.?

    The top 3 most reliable airlines when flying from St. Louis to Washington, D.C. are Avianca (72%), GoJet (71%) and United Airlines (71%).

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

    While on average a flight from St. Louis to Washington, D.C. is generally $788, our data shows the cheapest flight currently is $171. When looking at the most popular route, (Lambert-St Louis - Washington, D.C. Dulles Intl), you can expect to pay $221 for that flight.

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

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

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

    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, D.C..

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

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

    Currently, December is the cheapest month in which you can book a flight from St. Louis to Washington, D.C. (average of $98). Flying from St. Louis to Washington, D.C. in March is currently the most expensive (average of $201). 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 Washington, D.C.?

Book flights to Washington, D.C. if you plan to visit one of these locations
Alexandria
Woodbridge
Tysons
Owings Mills
Arlington
Springfield
Silver Spring
Herndon
Hyattsville
Hanover
Laurel
Rockville
Upper Marlboro
Fredericksburg
Largo
Bowie
Clinton
Towson
College Park
Cordova

Browse thousands of different options on Cheapflights for your next trip

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

Discover the top 5 airlines that operate flights from St. Louis to Washington, D.C.. 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
DeltaCheapest$99Average$285FlexibilityNo cancel feeOn-timeN/A
FrontierCheapest$113Average$214FlexibilityNo cancel feeOn-time62%
American AirlinesCheapest$156Average$335FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$197Average$359FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$264Average$453FlexibilityNo cancel feeOn-time69%

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