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Reagan-National

$119+ 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 7/29. Fares are subject to change and may not be available on all flights or dates of travel.
STL — DCA
Jul 17 — Jul 241
Fri 7/17
Fri 7/24
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. Reagan-National are usually found in September or August, booked 87 days in advance, depart on a Tuesday or Saturday and return on a Wednesday

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 June 17, 2026.

This Expedia deal was found by Cheapflights users on 6/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/78:08 pm
STL
-
DCA
1 stop24h 51m
Frontier
Mon 7/137:00 am
DCA
-
STL
1 stop13h 23m
Frontier
Deal found 6/15$263
This Delta deal was found by Cheapflights users on 6/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/412:30 pm
STL
-
DCA
1 stop5h 29m
Delta
Thu 8/66:20 am
DCA
-
STL
1 stop6h 27m
Delta
Deal found 6/14$264
This Delta deal was found by Cheapflights users on 6/14. 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 7/13:57 pm
STL
-
DCA
1 stop5h 50m
Delta
Tue 7/77:37 pm
DCA
-
STL
1 stop5h 16m
Delta
Deal found 6/14$267
This Expedia deal was found by Cheapflights users on 6/14. 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 7/98:08 pm
STL
-
DCA
1 stop24h 51m
Frontier
Mon 7/137:00 am
DCA
-
STL
1 stop13h 23m
Frontier
Deal found 6/14$268
This Southwest deal was found by Cheapflights users on 6/13. 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.
Thu 8/63:55 pm
STL
-
DCA
Nonstop2h 00m
Southwest
Mon 8/108:15 am
DCA
-
STL
Nonstop2h 20m
Southwest
Deal found 6/13$269
This Southwest deal was found by Cheapflights users on 6/13. 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.
Thu 9/33:15 pm
STL
-
DCA
1 stop6h 30m
Southwest
Mon 9/78:15 am
DCA
-
STL
Nonstop2h 20m
Southwest
Deal found 6/13$270
This Delta deal was found by Cheapflights users on 6/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/246:00 am
STL
-
DCA
1 stop5h 42m
Delta
Sat 9/2612:32 pm
DCA
-
STL
1 stop3h 42m
Delta
Deal found 6/16$271
This Delta deal was found by Cheapflights users on 6/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/66:30 am
STL
-
DCA
1 stop3h 58m
Delta
Mon 8/109:00 am
DCA
-
STL
1 stop6h 33m
Delta
Deal found 6/16$272
This Delta deal was found by Cheapflights users on 6/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/143:58 pm
STL
-
DCA
1 stop4h 51m
Delta
Thu 7/166:20 am
DCA
-
STL
1 stop6h 27m
Delta
Deal found 6/17$273
This Super.com deal was found by Cheapflights users on 6/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/228:08 pm
STL
-
DCA
1 stop15h 43m
Frontier
Thu 7/236:00 pm
DCA
-
STL
1 stop26h 23m
Frontier
Deal found 6/16$274
This Southwest deal was found by Cheapflights users on 6/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/157:55 pm
STL
-
DCA
Nonstop2h 00m
Southwest
Sat 7/184:10 pm
DCA
-
STL
Nonstop2h 20m
Southwest
Deal found 6/16$276
This American Airlines deal was found by Cheapflights users on 6/17. 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 7/273:20 pm
STL
-
DCA
1 stop5h 06m
American Airlines
Mon 8/38:00 pm
DCA
-
STL
Nonstop2h 21m
American Airlines
Deal found 6/17$277

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 June 17, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$263
(Expedia)

One-way from

$119
(Southwest)

Popular in

February

Cheapest in

September

Average price

$365

Good round-trip deal

$322 or less

Good one-way deal

$203 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. 18% potential increase in price ($84 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 6% potential price decrease ($21 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in June 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 June 17, 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

Wed 8/5

3:30 pm-6:35 pm

Nonstop2h 05m

Washington, D.C. Reagan-National

Sat 8/8

6:00 am-1:15 pm

2 stops8h 15m

$268

St. LouisWashington, D.C.

STL - DCA

STLDCA

Lambert-St Louis

Thu 9/24

6:00 am-12:42 pm

1 stop5h 42m

Washington, D.C. Reagan-National

Sat 9/26

9:00 am-12:22 pm

1 stop4h 22m

$271

St. LouisWashington, D.C.

STL - DCA

STLDCA

Lambert-St Louis

Mon 9/14

10:10 am-6:00 pm

1 stop6h 50m

Washington, D.C. Reagan-National

Thu 9/17

4:30 pm-10:05 pm

1 stop6h 35m

$271

St. LouisWashington, D.C.

STL - DCA

STLDCA

Lambert-St Louis

Wed 7/8

7:55 pm-10:55 pm

Nonstop2h 00m

Washington, D.C. Reagan-National

Mon 7/13

6:40 pm-8:00 pm

Nonstop2h 20m

$276

St. LouisWashington, D.C.

STL - DCA

STLDCA

Lambert-St Louis

Tue 7/14

2:10 pm-9:55 pm

1 stop6h 45m

Washington, D.C. Reagan-National

Mon 7/20

6:40 pm-8:00 pm

Nonstop2h 20m

$286

St. LouisWashington, D.C.

STL - DCA

STLDCA

Lambert-St Louis

Fri 7/24

12:28 pm-8:59 pm

1 stop7h 31m

Washington, D.C. Reagan-National

Wed 8/5

6:00 am-11:46 am

1 stop6h 46m

$307
Quickest round-trip

St. LouisWashington, D.C.

STL - DCA

STLDCA

Lambert-St Louis

Sun 8/23

8:10 am-11:10 am

Nonstop2h 00m

Washington, D.C. Reagan-National

Wed 9/2

6:50 pm-8:00 pm

Nonstop2h 10m

$309

St. LouisWashington, D.C.

STL - DCA

STLDCA

Lambert-St Louis

Mon 7/20

7:55 pm-10:55 pm

Nonstop2h 00m

Washington, D.C. Reagan-National

Thu 7/23

8:00 am-9:10 am

Nonstop2h 10m

$315

St. LouisWashington, D.C.

STL - DCA

STLDCA

Lambert-St Louis

Sun 8/23

1:00 pm-4:00 pm

Nonstop2h 00m

Washington, D.C. Reagan-National

Thu 9/3

12:15 pm-1:25 pm

Nonstop2h 10m

$316

St. LouisWashington, D.C.

STL - DCA

STLDCA

Lambert-St Louis

Sun 8/30

6:15 am-12:20 pm

1 stop5h 05m

Washington, D.C. Reagan-National

Tue 9/1

6:50 pm-8:00 pm

Nonstop2h 10m

$319

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/16

Showing 1-10 of 22 resultsSorted by cheapest first
1
2
3

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 June.
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?

The best time to book flights from St. Louis to Washington, D.C. Reagan-National Airport is 86 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, September is the cheapest month in which you can book a flight from St. Louis to Washington, D.C. Reagan-National Airport (average of $283). Flying from St. Louis to Washington, D.C. Reagan-National Airport in February is currently the most expensive (average of $590). 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 June 17, 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 12% on the cost of your flight, compared to a flight in the evening.

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

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 June 17, 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
7.9
Good
4,235 reviews

Overall

7.9

Boarding

8.1

Comfort

8.0

Entertainment

7.5

Crew

8.6

Food

7.0

Reviews

1 / 20
8.0
Excellent

La Tracimeldamarcos,Jun 2026

LAX - SLC

The second flight was not as comfortable as the first as we had to change planes to what seemed to be a slightly older aircraft. The seats weren’t as comfortable as the other plane. But it wasn’t bad.
Southwest
7.9
Good
4,235 reviews
Southwest
7.9
Good
4,235 reviews

Overall

7.9

Boarding

8.1

Comfort

8.0

Entertainment

7.5

Crew

8.6

Food

7.0

Reviews

1 / 20
8.0
Excellent

La Tracimeldamarcos,Jun 2026

LAX - SLC

The second flight was not as comfortable as the first as we had to change planes to what seemed to be a slightly older aircraft. The seats weren’t as comfortable as the other plane. But it wasn’t bad.
American Airlines
7.1
Good
11,670 reviews
Southwest
7.9
Good
4,235 reviews

Overall

7.9

Boarding

8.1

Comfort

8.0

Entertainment

7.5

Crew

8.6

Food

7.0

Reviews

1 / 20
8.0
Excellent

La Tracimeldamarcos,Jun 2026

LAX - SLC

The second flight was not as comfortable as the first as we had to change planes to what seemed to be a slightly older aircraft. The seats weren’t as comfortable as the other plane. But it wasn’t bad.
Frontier
5.6
Fair
2,881 reviews
Southwest
7.9
Good
4,235 reviews

Overall

7.9

Boarding

8.1

Comfort

8.0

Entertainment

7.5

Crew

8.6

Food

7.0

Reviews

1 / 20
8.0
Excellent

La Tracimeldamarcos,Jun 2026

LAX - SLC

The second flight was not as comfortable as the first as we had to change planes to what seemed to be a slightly older aircraft. The seats weren’t as comfortable as the other plane. But it wasn’t bad.

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 4 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 and Delta fly from St. Louis to Washington, D.C. Reagan-National Airport in about 2h 05m. The time it takes to get you to your destination can typically vary by up to 3h 37m. The distance from St. Louis to Washington, D.C. Reagan-National Airport is about 717 mi. 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 St. Louis to Washington, D.C. Reagan-National Airport round-trip?

    According to our current data, Frontier ($96), American Airlines ($178), and Southwest ($198) offers the cheapest pricing from St. Louis to Washington, D.C. Reagan-National Airport. Frontier is priced at 73% 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: American Airlines (71%), PSA Airlines (71%), Southwest( 63%).

  • 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 $353, our data shows the cheapest flight currently is $157. 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, September is the cheapest month in which you can book a flight from St. Louis to Washington, D.C. Reagan-National Airport (average of $283). Flying from St. Louis to Washington, D.C. Reagan-National Airport in February is currently the most expensive (average of $590). 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
Arlington
Tysons
Owings Mills
Springfield
Lanham
Reston
Herndon
Rockville
Hyattsville
Manassas
Fredericksburg
Laurel
Hanover
Falls Church
Waldorf
Silver Spring
Largo
Clinton
Hunt Valley

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 June 17, 2026.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$96Average$223FlexibilityNo cancel feeOn-time62%
American AirlinesCheapest$178Average$331FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$198Average$359FlexibilityNo cancel feeOn-time63%

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