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Reagan-National

$96+ Cheap flights from St. Louis (STL) to Reagan-National (DCA)

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 5/4. Fares are subject to change and may not be available on all flights or dates of travel.
STL — DCA
Apr 22 — Apr 291
Wed 4/22
Wed 4/29
1 adult, Economy
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Cheapflights Tip: The best prices from Lambert-St Louis to Washington, D.C. Reagan-National are usually found in August or September, booked 50 days in advance, depart on a Saturday or Tuesday and return on a Tuesday

Cheap flight deals from St. Louis to Reagan-National

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

This Expedia deal was found by Cheapflights users on 3/22. 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.
Fri 4/178:06 pm
STL
-
DCA
1 stop15h 54m
Frontier
Sat 4/186:00 pm
DCA
-
STL
1 stop26h 21m
Frontier
Deal found 3/22$246
This Trip.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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 3/308:12 pm
STL
-
DCA
1 stop14h 52m
Frontier
Thu 4/27:00 am
DCA
-
STL
1 stop27h 48m
Frontier
Deal found 3/21$247
This Southwest deal was found by Cheapflights users on 3/22. 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 5/25:15 am
STL
-
DCA
2 stops7h 45m
Southwest
Tue 5/510:55 am
DCA
-
STL
1 stop8h 00m
Southwest
Deal found 3/22$248
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/153:40 pm
STL
-
DCA
Nonstop2h 00m
Southwest
Sat 4/186:25 pm
DCA
-
STL
Nonstop2h 25m
Southwest
Deal found 3/19$251
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/212:10 pm
STL
-
DCA
2 stops7h 15m
Southwest
Wed 4/2212:00 pm
DCA
-
STL
Nonstop2h 25m
Southwest
Deal found 3/18$252
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/298:05 am
STL
-
DCA
Nonstop2h 00m
Southwest
Thu 4/303:35 pm
DCA
-
STL
1 stop4h 05m
Southwest
Deal found 3/18$257
This American Airlines 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/186:00 am
STL
-
DCA
Nonstop2h 15m
American Airlines
Wed 5/208:12 am
DCA
-
STL
Nonstop2h 25m
American Airlines
Deal found 3/20$262
This Southwest deal was found by Cheapflights users on 3/22. 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.
Wed 5/133:40 pm
STL
-
DCA
Nonstop2h 00m
Southwest
Fri 5/156:35 pm
DCA
-
STL
1 stop6h 20m
Southwest
Deal found 3/22$264
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/183:25 pm
STL
-
DCA
Nonstop2h 00m
Southwest
Sat 4/256:25 pm
DCA
-
STL
Nonstop2h 25m
Southwest
Deal found 3/20$265
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/186:10 am
STL
-
DCA
2 stops9h 05m
Southwest
Tue 4/218:00 am
DCA
-
STL
Nonstop2h 20m
Southwest
Deal found 3/20$266
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/192:10 pm
STL
-
DCA
2 stops7h 15m
Southwest
Wed 5/2011:40 am
DCA
-
STL
2 stops7h 20m
Southwest
Deal found 3/18$267

Find flight deals from St. Louis to Reagan-National

Discover tips and strategies to find the most affordable flight options for your journey from St. Louis (STL) to Reagan-National (DCA). 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

$246
(Expedia)

One-way from

$96
(Expedia)

Popular in

February

Cheapest in

August

Average price

$388

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. Reagan-National flight deals.
Search Deals
Provider most trusted by Cheapflights users for Lambert-St Louis-Washington, D.C. Reagan-National flights.
Search Deals
From Lambert-St Louis to Washington, D.C. Reagan-National
Search Deals
One-way flight from Lambert-St Louis to Washington, D.C. Reagan-National
Search Deals
Highest demand for flights based on searches. 24% potential increase in price ($107 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 7% potential price decrease ($24 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. Reagan-National.
Search Deals
Price to beat on a one-way flight from Lambert-St Louis to Washington, D.C. Reagan-National.
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from St. Louis to Reagan-National 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. Reagan-National Airport 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
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 - 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 - DCA

STLDCA

Lambert-St Louis

Fri 5/8

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

$331

St. LouisWashington, D.C.

STL - DCA

STLDCA

Lambert-St Louis

Wed 6/3

2:10 pm-10:25 pm

2 stops7h 15m

Washington, D.C. Reagan-National

Sun 6/14

6:40 pm-8:00 pm

Nonstop2h 20m

$363

St. LouisWashington, D.C.

STL - DCA

STLDCA

Lambert-St Louis

Thu 6/11

6:00 am-1:10 pm

1 stop6h 10m

Washington, D.C. Reagan-National

Sun 6/14

6:00 am-9:30 am

1 stop4h 30m

$368

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/23

Showing 1-10 of 23 resultsSorted by cheapest first
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Compare providers for flights from St. Louis to Reagan-National

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 Reagan-National 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 St. Louis-Washington, D.C. Reagan-National Airport 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. Reagan-National Airport flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from St. Louis-Washington, D.C. Reagan-National Airport flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on St. Louis-Washington, D.C. Reagan-National Airport 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. Reagan-National Airport 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 Reagan-National

Have a flexible travel schedule? Discover the best time to fly to Reagan-National 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. Reagan-National Airport

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

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

The best time to book flights from St. Louis to Washington, D.C. Reagan-National Airport is 50 days before your desired departure date. The cost of your flight will likely increase significantly if you book two weeks in advance of your flight.

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

Currently, July is the cheapest month in which you can book a flight from St. Louis to Washington, D.C. Reagan-National Airport (average of $102). Flying from St. Louis to Washington, D.C. Reagan-National Airport in December is currently the most expensive (average of $268). 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 DCA?

Find hourly flight availability from St. Louis to Reagan-National. 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 St. Louis to Washington, D.C. Reagan-National Airport at noon. By choosing this option you can save up to 6% on the cost of your flight, compared to a flight in the morning.

The best insider tips for St. Louis to Washington, D.C. Reagan-National Airport 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. Reagan-National Airport 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

Reviews of airlines servicing Reagan-National

Get insights into the airlines that provide service to Reagan-National. 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 Reagan-National. Reviews last updated March 23, 2026.
Get a feel of what it's like to fly with Southwest,American Airlines, andFrontier from St. Louis to Washington, D.C. Reagan-National Airport 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

Entertainment

7.5

Food

7.0

Crew

8.6

Comfort

8.0

Boarding

8.1

Overall

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

Entertainment

7.5

Food

7.0

Crew

8.6

Comfort

8.0

Boarding

8.1

Overall

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

Entertainment

7.5

Food

7.0

Crew

8.6

Comfort

8.0

Boarding

8.1

Overall

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

Entertainment

7.5

Food

7.0

Crew

8.6

Comfort

8.0

Boarding

8.1

Overall

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 Reagan-National. 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. Reagan-National?

    Most people fly from Lambert-St Louis (STL) if they book a flight from St. Louis to Washington, D.C. Reagan-National. On average, Lambert-St Louis has 5 outbound flights to Washington, D.C. Reagan-National per day from 3 airlines. Lambert-St Louis is conveniently located just 12.7 mi from St. Louis’s city center.

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

    Airlines like Southwest fly from St. Louis to Washington, D.C. Reagan-National Airport in about 2h. The time it takes to get you to your destination is usually consistent. The distance from St. Louis to Washington, D.C. Reagan-National Airport is about 717 mi. Most flights are nonstop.

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

    According to our current data, Frontier ($145), American Airlines ($156), and Southwest ($197) offers the cheapest pricing from St. Louis to Washington, D.C. Reagan-National Airport. Frontier is priced at 56% lower than the current average price of a flight leaving 3 months from now.

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

    Before booking your flight to Washington, D.C. Reagan-National Airport from St. Louis, check out the most reliable airlines to get you to your destination on time: Republic Airways (76%), Southwest (67%), American Airlines( 66%).

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

    While on average a flight from St. Louis to Washington, D.C. Reagan-National Airport is generally $404, our data shows the cheapest flight currently is $118. When looking at the most popular route, (Lambert-St Louis - Washington, D.C. Reagan-National), you can expect to pay $237 for that flight.

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

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

  • How can I find direct flights from St. Louis to Reagan-National?

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

  • Can I find deals for business class flights from St. Louis to Reagan-National?

    Yes. Cheapflights offers flight deals from St. Louis to Reagan-National 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. Reagan-National Airport?

    Currently, July is the cheapest month in which you can book a flight from St. Louis to Washington, D.C. Reagan-National Airport (average of $102). Flying from St. Louis to Washington, D.C. Reagan-National Airport in December is currently the most expensive (average of $268). 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. Reagan-National Airport?

Book flights to Washington, D.C. Reagan-National Airport 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 3 airlines flying from St. Louis to Reagan-National

Discover the top 3 airlines that operate flights from St. Louis to Reagan-National. 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$145Average$242FlexibilityNo cancel feeOn-time62%
American AirlinesCheapest$156Average$300FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$197Average$326FlexibilityNo cancel feeOn-time63%

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