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

According to our current data, American Airlines ($207), and Southwest ($237) offers the cheapest pricing from Washington, D.C. Reagan-National Airport to St. Louis. American Airlines is 47% cheaper than the average price of flights available within the next 90 days to this destination.

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

To fly one-way, consider booking your trip with United Airlines, which is currently one of the cheapest options available, starting at $100. American Airlines flights start at $123 while deals on Southwest start at $128 one-way.

In terms of precipitation, rainfall in St. Louis ranges from 2.2 - 4.7 inches per month. May is typically the wettest month, when rainfall can reach 4.7 in. February is typically the driest time to visit St. Louis when rainfall is around 2.2 in.

If weather is an important factor for your trip to St. Louis, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 80.6 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 32.0 F).

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

Looking at all options, your cheapest flight can be booked for $139. While the most popular route (Washington, D.C. Reagan-National - Lambert-St Louis) can be booked for $237 on average, our data indicates $320 when flying from Washington, D.C. Reagan-National Airport to St. Louis.

What are the most reliable airlines from Washington, D.C. Reagan-National Airport 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. Reagan-National Airport to St. Louis on time: American Airlines (54%), Republic Airways (54%), PSA Airlines (47%).

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

Most trusted provider : When it comes to deals on Washington, D.C. Reagan-National Airport-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. Reagan-National Airport-St. Louis flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

What airport do you fly into for flights to St. Louis from Washington, D.C. Reagan-National?

Lambert-St Louis (STL) is the airport you will fly into if you book a flight from Washington, D.C. Reagan-National to St. Louis. You should not have trouble finding flights to Lambert-St Louis from Washington, D.C. Reagan-National; the airport handles an average of 3 inbound flights from Washington, D.C. Reagan-National per day. You should also have plenty of airline options to choose from since 2 airlines have flights to the St. Louis airport from Washington, D.C. Reagan-National. It is only a 12.7 mi journey from Lambert-St Louis (STL) to St. Louis’s city center.

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

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

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

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

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

Yes. Cheapflights offers flight deals from Reagan-National 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.

$128+ Cheap Flights from Washington, D.C. Reagan-National Airport to St. Louis

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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

We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.

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Cheapflights Tip: The best prices from Washington, D.C. Reagan-National to Lambert-St Louis are usually found in January or October, booked 48 days in advance, depart on a Wednesday or Thursday and return on a Saturday

Cheap flight deals from Reagan-National to St. Louis

Cheapest

Best

Last-minute

One-way

Cheapest flights from Reagan-National to St. Louis
Explore the most affordable flight options available from Reagan-National to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on August 25, 2026.

Wed 10/216:59 am -

1 stop4h 52m

Mon 10/266:24 pm -

1 stop3h 43m

Deal found 8/21

$237

Thu 9/106:00 pm -

1 stop26h 17m

Mon 9/148:10 pm -

1 stop19h 49m

Deal found 8/21

$239

Sat 9/191:06 pm -

1 stop7h 11m

Sun 9/208:10 pm -

1 stop15h 01m

Deal found 8/24

$240

Sat 10/36:55 am -

2 stops10h 10m

Sat 10/101:45 pm -

1 stop4h 15m

Deal found 8/21

$242

Tue 10/136:00 pm -

1 stop22h 24m

Fri 10/168:00 pm -

1 stop19h 56m

Deal found 8/20

$243

Fri 9/256:50 pm -

Nonstop2h 10m

Wed 9/304:45 pm -

1 stop5h 30m

Deal found 8/21

$246

Wed 10/2110:35 am -

1 stop5h 20m

Thu 10/227:50 pm -

Nonstop2h 00m

Deal found 8/23

$247

Fri 9/186:00 pm -

1 stop26h 17m

Mon 9/218:10 pm -

1 stop24h 49m

Deal found 8/21

$249

Sun 9/207:00 am -

1 stop13h 17m

Fri 9/258:10 pm -

1 stop24h 49m

Deal found 8/25

$251

Mon 9/218:15 am -

Nonstop2h 20m

Mon 9/2810:10 am -

2 stops6h 50m

Deal found 8/24

$252

Fri 10/236:00 pm -

1 stop25h 57m

Wed 10/284:18 pm -

1 stop23h 29m

Deal found 8/23

$253

Fri 9/117:40 pm -

1 stop5h 02m

Sat 9/192:00 pm -

1 stop5h 38m

Deal found 8/21

$256

Best flights from Reagan-National to St. Louis
Discover carefully curated flight deals from Reagan-National to St. Louis that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated August 25, 2026.

Mon 11/236:10 am -

1 stop4h 55m

Tue 12/12:20 pm -

1 stop6h 35m

Deal found 8/20

$237

Tue 10/277:40 pm -

1 stop5h 14m

Thu 10/295:35 pm -

1 stop4h 14m

Deal found 8/24

$257

Sat 9/126:40 pm -

Nonstop2h 15m

Mon 9/147:55 pm -

Nonstop2h 00m

Deal found 8/22

$237

Mon 10/193:25 pm -

Nonstop2h 30m

Wed 10/2110:20 am -

1 stop3h 10m

Deal found 8/24

$243

Sat 9/196:30 am -

2 stops7h 45m

Sat 9/196:50 pm -

Nonstop2h 00m

Deal found 8/23

$252

Mon 9/218:15 am -

Nonstop2h 20m

Mon 9/2810:10 am -

2 stops6h 50m

Deal found 8/24

$252

Mon 9/211:30 pm -

1 stop6h 40m

Tue 9/2212:50 pm -

1 stop5h 20m

Deal found 8/22

$257

Tue 9/151:15 pm -

1 stop7h 40m

Sat 9/195:05 am -

2 stops7h 50m

Deal found 8/20

$261

Wed 9/3011:40 am -

2 stops7h 15m

Fri 10/22:30 pm -

1 stop3h 55m

Deal found 8/21

$271

Thu 9/178:15 am -

Nonstop2h 20m

Sun 9/207:50 pm -

Nonstop2h 00m

Deal found 8/20

$292

Last-minute flights from Reagan-National to St. Louis
Discover last-minute flight deals from Reagan-National to St. Louis. Data last updated August 25, 2026 and is based on user searches.

Thu 9/106:00 pm -

1 stop26h 17m

Mon 9/148:10 pm -

1 stop19h 49m

Deal found 8/21

$239

Fri 9/117:40 pm -

1 stop5h 02m

Sat 9/192:00 pm -

1 stop5h 38m

Deal found 8/21

$256

Sat 9/126:32 pm -

1 stop6h 10m

Thu 9/1710:29 am -

1 stop7h 08m

Deal found 8/21

$237

Tue 9/1511:40 am -

2 stops7h 15m

Sat 9/198:25 am -

1 stop6h 50m

Deal found 8/21

$242

Wed 9/1612:00 pm -

Nonstop2h 15m

Fri 9/181:10 pm -

Nonstop2h 00m

Deal found 8/22

$258

Fri 9/186:00 pm -

1 stop26h 17m

Mon 9/218:10 pm -

1 stop24h 49m

Deal found 8/21

$249

Sat 9/191:06 pm -

1 stop7h 11m

Sun 9/208:10 pm -

1 stop15h 01m

Deal found 8/24

$240

Sun 9/207:00 am -

1 stop13h 17m

Fri 9/258:10 pm -

1 stop24h 49m

Deal found 8/25

$251

Mon 9/218:15 am -

Nonstop2h 20m

Mon 9/282:20 pm -

1 stop6h 35m

Deal found 8/24

$247

Mon 9/211:30 pm -

1 stop6h 40m

Tue 9/2212:50 pm -

1 stop5h 20m

Deal found 8/24

$257

Fri 9/256:50 pm -

Nonstop2h 10m

Wed 9/304:45 pm -

1 stop5h 30m

Deal found 8/21

$246

One-way flights from Reagan-National to St. Louis
Search for one-way flight options from Reagan-National to St. Louis. Find affordable one-way fares based on user searches. Data last updated August 25, 2026.

Fri 10/212:00 pm -

Nonstop2h 25m

Deal found 8/21

$128

Tue 9/2212:32 pm -

1 stop5h 38m

Deal found 8/25

$129

Sat 9/266:00 pm -

2 stops44h 10m

Deal found 8/24

$130

Wed 9/91:00 pm -

1 stop7h 17m

Deal found 8/21

$131

Fri 2/193:35 pm -

1 stop4h 15m

Deal found 8/20

$133

Sat 10/246:55 am -

2 stops10h 10m

Deal found 8/25

$134

Sun 9/207:00 am -

1 stop13h 17m

Deal found 8/23

$137

Fri 10/98:05 pm -

1 stop5h 30m

Deal found 8/21

$138

Fri 9/252:54 pm -

Nonstop2h 33m

Deal found 8/25

$140

Sun 10/46:00 pm -

1 stop26h 17m

Deal found 8/23

$142

Sat 9/194:15 pm -

Nonstop2h 24m

Deal found 8/21

$149

Fri 9/188:24 pm -

1 stop5h 03m

Deal found 8/25

$150

Find flight deals from Reagan-National to St. Louis

Most accurate provider	FlightHub 3 stars
Most trusted provider	FlightHub 3 stars
Round-trip from	$237 (Delta)
One-way from	$128 (Southwest)
Popular in	December
Cheapest in	January
Average price	$391
Good round-trip deal	$286 or less
Good one-way deal	$213 or less

Provider with most accurate pricing for Washington, D.C. Reagan-National-Lambert-St Louis flight deals.

Search Deals

Provider most trusted by Cheapflights users for Washington, D.C. Reagan-National-Lambert-St Louis flights.

Search Deals

From Washington, D.C. Reagan-National to Lambert-St Louis

Search Deals

One-way flight from Washington, D.C. Reagan-National to Lambert-St Louis

Search Deals

High demand for flights, 1% potential price rise

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 August 2026

Search Deals

Price to beat on a round-trip flight from Washington, D.C. Reagan-National to Lambert-St Louis.

Search Deals

Price to beat on a one-way flight from Washington, D.C. Reagan-National to Lambert-St Louis.

Search Deals

Cheapflights Fare Finder

Use the filters below to find and compare flights from Washington, D.C. Reagan-National Airport to St. Louis that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

Washington, D.C.St. Louis

DCA Washington, D.C. Reagan-National - STL Lambert-St Louis

DCASTL

Washington, D.C. Reagan-National

Mon 11/23

6:10 am-10:05 am

1 stop4h 55m

Lambert-St Louis

Tue 12/1

2:20 pm-9:55 pm

1 stop6h 35m

$237

Quickest round-trip

Washington, D.C.St. Louis

DCA Washington, D.C. Reagan-National - STL Lambert-St Louis

DCASTL

Washington, D.C. Reagan-National

Sat 9/12

6:40 pm-7:55 pm

Nonstop2h 15m

Lambert-St Louis

Mon 9/14

7:55 pm-10:55 pm

Nonstop2h 00m

$237

Washington, D.C.St. Louis

DCA Washington, D.C. Reagan-National - STL Lambert-St Louis

DCASTL

Washington, D.C. Reagan-National

Mon 10/19

3:25 pm-4:55 pm

Nonstop2h 30m

Lambert-St Louis

Wed 10/21

10:20 am-2:30 pm

1 stop3h 10m

$243

Washington, D.C.St. Louis

DCA Washington, D.C. Reagan-National - STL Lambert-St Louis

DCASTL

Washington, D.C. Reagan-National

Sat 9/19

6:30 am-1:15 pm

2 stops7h 45m

Lambert-St Louis

Sat 9/19

6:50 pm-9:50 pm

Nonstop2h 00m

$252

Washington, D.C.St. Louis

DCA Washington, D.C. Reagan-National - STL Lambert-St Louis

DCASTL

Washington, D.C. Reagan-National

Mon 9/21

8:15 am-9:35 am

Nonstop2h 20m

Lambert-St Louis

Mon 9/28

10:10 am-6:00 pm

2 stops6h 50m

$252

Washington, D.C.St. Louis

DCA Washington, D.C. Reagan-National - STL Lambert-St Louis

DCASTL

Washington, D.C. Reagan-National

Tue 10/27

7:40 pm-11:54 pm

1 stop5h 14m

Lambert-St Louis

Thu 10/29

5:35 pm-10:49 pm

1 stop4h 14m

$257

Washington, D.C.St. Louis

DCA Washington, D.C. Reagan-National - STL Lambert-St Louis

DCASTL

Washington, D.C. Reagan-National

Mon 9/21

1:30 pm-7:10 pm

1 stop6h 40m

Lambert-St Louis

Tue 9/22

12:50 pm-7:10 pm

1 stop5h 20m

$257

Washington, D.C.St. Louis

DCA Washington, D.C. Reagan-National - STL Lambert-St Louis

DCASTL

Washington, D.C. Reagan-National

Tue 9/15

1:15 pm-7:55 pm

1 stop7h 40m

Lambert-St Louis

Sat 9/19

5:05 am-1:55 pm

2 stops7h 50m

$261

Washington, D.C.St. Louis

DCA Washington, D.C. Reagan-National - STL Lambert-St Louis

DCASTL

Washington, D.C. Reagan-National

Wed 9/30

11:40 am-5:55 pm

2 stops7h 15m

Lambert-St Louis

Fri 10/2

2:30 pm-7:25 pm

1 stop3h 55m

$271

Washington, D.C.St. Louis

DCA Washington, D.C. Reagan-National - STL Lambert-St Louis

DCASTL

Washington, D.C. Reagan-National

Thu 9/17

8:15 am-9:35 am

Nonstop2h 20m

Lambert-St Louis

Sun 9/20

7:50 pm-10:50 pm

Nonstop2h 00m

$292

Flights are sorted by cheapest round-trip flights first.

Deals found on 8/21

Showing 1-10 of 20 resultsSorted by cheapest first

Compare providers for flights from Reagan-National to St. Louis

Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Reagan-National to St. Louis in August.

Provider	Price Accuracy	Trust Score*
Expedia	Price Accuracy1 star	Trust Score*3 stars
FlightHub	Price Accuracy3 stars	Trust 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 Washington, D.C. Reagan-National Airport-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. Reagan-National Airport-St. Louis flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Washington, D.C. Reagan-National Airport-St. Louis flight searches over the past month and is updated monthly.
Most trusted provider: When it comes to deals on Washington, D.C. Reagan-National Airport-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. Reagan-National Airport-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 Reagan-National to St. Louis

Have a flexible travel schedule? Discover the best time to fly to St. Louis from Reagan-National with our price prediction graph.

DCA-STL

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. Reagan-National Airport to St. Louis

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

The best time to book flights from Washington, D.C. Reagan-National Airport to St. Louis is 47 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 Washington, D.C. Reagan-National Airport to St. Louis?

Currently, January is the cheapest month in which you can book a flight from Washington, D.C. Reagan-National Airport to St. Louis (average of $309). Flying from Washington, D.C. Reagan-National Airport to St. Louis in December is currently the most expensive (average of $458). 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 DCA to STL?

It’s optimal to fly from Washington, D.C. Reagan-National Airport to St. Louis at noon. By choosing this option you can save up to 7% on the cost of your flight, compared to a flight in the evening.

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

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

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

Airfare is below average for this route at the moment.

Washington, D.C. Reagan-National Airport to St. Louis flights typically cost between $284 and $486 in October.
The cheapest round-trip price found within the last 5 days was $237 on Delta (Oct 21-Oct 26).

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

Cheapflights partnered with top experts to bring you the best recommendations for your Washington, D.C. Reagan-National Airport to St. Louis trip

Our travel experts

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.

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.

Peruse reviews from past customers who have flown with Southwest and American Airlines from Washington, D.C. Reagan-National Airport to St. Louis to help guide your decision. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.

Southwest

8.0

Very good

4,208 reviews

Reviews

1 / 20

8.0

Excellent

Libby,Jun 2026

TUS - LAS

One delay in a 2 layover flight=a good trip. The crew was great.

Southwest

8.0

Very good

4,208 reviews

Southwest

8.0

Very good

4,208 reviews

Reviews

1 / 20

8.0

Excellent

Libby,Jun 2026

TUS - LAS

One delay in a 2 layover flight=a good trip. The crew was great.

American Airlines

7.1

Good

11,990 reviews

Southwest

8.0

Very good

4,208 reviews

Reviews

1 / 20

8.0

Excellent

Libby,Jun 2026

TUS - LAS

One delay in a 2 layover flight=a good trip. The crew was great.

Related info for your journey

What airport do you fly into for flights to St. Louis from Washington, D.C. Reagan-National?
Lambert-St Louis (STL) is the airport you will fly into if you book a flight from Washington, D.C. Reagan-National to St. Louis. You should not have trouble finding flights to Lambert-St Louis from Washington, D.C. Reagan-National; the airport handles an average of 3 inbound flights from Washington, D.C. Reagan-National per day. You should also have plenty of airline options to choose from since 2 airlines have flights to the St. Louis airport from Washington, D.C. Reagan-National. It is only a 12.7 mi journey from Lambert-St Louis (STL) to St. Louis’s city center.
How long is the flight from Washington, D.C. Reagan-National Airport to St. Louis?
For as low as $237, Southwest can have you in St. Louis from Washington, D.C. Reagan-National Airport in 4h 55m. The distance between Washington, D.C. Reagan-National Airport and St. Louis is about 717 mi.
What are the cheapest airlines flying from Washington, D.C. Reagan-National Airport to St. Louis round-trip?
According to our current data, American Airlines ($207), and Southwest ($237) offers the cheapest pricing from Washington, D.C. Reagan-National Airport to St. Louis. American Airlines is 47% cheaper than the average price of flights available within the next 90 days to this destination.
What are the cheapest airlines to fly from Washington, D.C. Reagan-National Airport to St. Louis one-way?
To fly one-way, consider booking your trip with United Airlines, which is currently one of the cheapest options available, starting at $100. American Airlines flights start at $123 while deals on Southwest start at $128 one-way.
What are the most reliable airlines from Washington, D.C. Reagan-National Airport 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. Reagan-National Airport to St. Louis on time: American Airlines (54%), Republic Airways (54%), PSA Airlines (47%).
What are the cheapest flights from Washington, D.C. Reagan-National Airport to St. Louis?
Looking at all options, your cheapest flight can be booked for $139. While the most popular route (Washington, D.C. Reagan-National - Lambert-St Louis) can be booked for $237 on average, our data indicates $320 when flying from Washington, D.C. Reagan-National Airport to St. Louis.
Can I find deals for flights from Reagan-National to St. Louis that include hotel bookings?
Yes. In addition to deals on Reagan-National to St. Louis flights, Cheapflights offers vacation packages that include both flights and hotel.
How can I find direct flights from Reagan-National to St. Louis?
After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Reagan-National to St. Louis.
Can I find deals for business class flights from Reagan-National to St. Louis?
Yes. Cheapflights offers flight deals from Reagan-National 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. Reagan-National Airport to St. Louis?
Currently, January is the cheapest month in which you can book a flight from Washington, D.C. Reagan-National Airport to St. Louis (average of $309). Flying from Washington, D.C. Reagan-National Airport to St. Louis in December is currently the most expensive (average of $458). 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

Edwardsville

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O'Fallon

Fenton

Swansea

Eureka

Maryland Heights

Collinsville

Wentzville

Glencoe

Chesterfield

Farmington

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Alternative routes

Complete your trip

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Other flights from Reagan-National

Popular flights

St. Louis flight routes

Top 2 airlines flying from Reagan-National to St. Louis

Airline	Cheapest	Average	Flexibility	On-time
American Airlines	Cheapest$207	Average$383	FlexibilityNo cancel fee	On-time71%
Southwest	Cheapest$237	Average$402	FlexibilityNo cancel fee	On-time63%

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$128+ Cheap flights from Reagan-National (DCA) 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 10/2. Fares are subject to change and may not be available on all flights or dates of travel.

Find cheap flights from Reagan-National to St. Louis with Cheapflights

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Cheap flight deals from Reagan-National to St. Louis

Cheapest flights from Reagan-National to St. LouisExplore the most affordable flight options available from Reagan-National to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on August 25, 2026.

Explore the most affordable flight options available from Reagan-National to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on August 25, 2026.

Best flights from Reagan-National to St. LouisDiscover carefully curated flight deals from Reagan-National to St. Louis that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated August 25, 2026.

Discover carefully curated flight deals from Reagan-National to St. Louis that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated August 25, 2026.

Last-minute flights from Reagan-National to St. LouisDiscover last-minute flight deals from Reagan-National to St. Louis. Data last updated August 25, 2026 and is based on user searches.

Discover last-minute flight deals from Reagan-National to St. Louis. Data last updated August 25, 2026 and is based on user searches.

One-way flights from Reagan-National to St. LouisSearch for one-way flight options from Reagan-National to St. Louis. Find affordable one-way fares based on user searches. Data last updated August 25, 2026.

Search for one-way flight options from Reagan-National to St. Louis. Find affordable one-way fares based on user searches. Data last updated August 25, 2026.

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Best time to book a flight from Reagan-National to St. Louis

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Cheapflights Insights

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

The best time to book flights from Washington, D.C. Reagan-National Airport to St. Louis is 47 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 Washington, D.C. Reagan-National Airport to St. Louis?

What is the cheapest time of day to fly from DCA to STL?

It’s optimal to fly from Washington, D.C. Reagan-National Airport to St. Louis at noon. By choosing this option you can save up to 7% on the cost of your flight, compared to a flight in the evening.

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

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

Airfare is below average for this route at the moment.

Washington, D.C. Reagan-National Airport to St. Louis flights typically cost between $284 and $486 in October.The cheapest round-trip price found within the last 5 days was $237 on Delta (Oct 21-Oct 26).

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

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Cheapflights partnered with top experts to bring you the best recommendations for your Washington, D.C. Reagan-National Airport to St. Louis trip

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Reagan-National and St. Louis flights

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Cheapest flights from Reagan-National to St. Louis
Explore the most affordable flight options available from Reagan-National to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on August 25, 2026.

Best flights from Reagan-National to St. Louis
Discover carefully curated flight deals from Reagan-National to St. Louis that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated August 25, 2026.

Last-minute flights from Reagan-National to St. Louis
Discover last-minute flight deals from Reagan-National to St. Louis. Data last updated August 25, 2026 and is based on user searches.

One-way flights from Reagan-National to St. Louis
Search for one-way flight options from Reagan-National to St. Louis. Find affordable one-way fares based on user searches. Data last updated August 25, 2026.

Washington, D.C. Reagan-National Airport to St. Louis flights typically cost between $284 and $486 in October.
The cheapest round-trip price found within the last 5 days was $237 on Delta (Oct 21-Oct 26).