Cheap flights from St. Louis to Washington, D.C. from $96

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from St. Louis to Washington, D.C. departing on 6/9. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
1 adult
0 bags

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Find the cheapest flights from St. Louis to Washington, D.C.

Cheap round-trip flights

Enter your travel dates to find the best prices.
American Airlines Logo
5:08 am - 8:28 am
STL
-
DCA
2h 20mnonstop
American Airlines Logo
8:00 pm - 9:29 pm
DCA
-
STL
2h 29mnonstop
$251American Airlines
Wed, May 27 - Mon, Jun 1
Southwest Logo
1:45 pm - 7:10 pm
STL
-
DCA
4h 25m
1 stop
Southwest Logo
11:45 am - 2:50 pm
DCA
-
STL
4h 05m
1 stop
$252Southwest
Tue, May 19 - Tue, Jun 9
United Airlines Logo
7:45 am - 2:14 pm
STL
-
DCA
5h 29m
1 stop
United Airlines Logo
11:57 am - 3:46 pm
DCA
-
STL
4h 49m
1 stop
$257United Airlines
Tue, May 19 - Wed, Jun 3
American Airlines Logo
5:08 am - 8:28 am
STL
-
DCA
2h 20mnonstop
American Airlines Logo
3:52 pm - 8:30 pm
DCA
-
STL
5h 38m
1 stop
$261American Airlines
Wed, May 27 - Mon, Jun 1
American Airlines Logo
6:00 am - 9:19 am
STL
-
DCA
2h 19mnonstop
American Airlines Logo
8:40 am - 10:12 am
DCA
-
STL
2h 32mnonstop
$265American Airlines
Sat, May 23 - Mon, May 25
Southwest Logo
10:55 am - 6:55 pm
STL
-
DCA
7h 00m
2 stops
Southwest Logo
6:50 pm - 8:15 pm
DCA
-
STL
2h 25mnonstop
$266Southwest
Sat, May 30 - Tue, Jun 2
Delta Logo
1:59 pm - 6:59 pm
STL
-
DCA
4h 00m
1 stop
Delta Logo
6:05 am - 9:29 am
DCA
-
STL
4h 24m
1 stop
$271Delta
Wed, May 27 - Thu, Jun 4
Southwest Logo
7:55 pm - 11:00 pm
STL
-
DCA
2h 05mnonstop
Southwest Logo
12:00 pm - 1:25 pm
DCA
-
STL
2h 25mnonstop
$273Southwest
Tue, May 26 - Sat, May 30
Southwest Logo
5:40 am - 11:10 am
STL
-
DCA
4h 30m
1 stop
Southwest Logo
8:00 am - 9:10 am
DCA
-
STL
2h 10mnonstop
$275Southwest
Thu, May 28 - Thu, Jun 4
Southwest Logo
7:55 pm - 11:00 pm
STL
-
DCA
2h 05mnonstop
Southwest Logo
8:00 am - 9:20 am
DCA
-
STL
2h 20mnonstop
$276Southwest
Tue, May 26 - Fri, May 29

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Frontier flights from St. Louis to Washington, D.C. Reagan-National Airport

Our best Frontier deals on St. Louis to Washington, D.C. Reagan-National Airport flight tickets
Frontier
May 23
STL8:08 pmLambert-St Louis
15h 51m
1 stop
DCA12:59 pmWashington, D.C. Reagan-National
May 25
DCA7:00 amWashington, D.C. Reagan-National
13h 23m
1 stop
STL7:23 pmLambert-St Louis
$251
Frontier
May 4
STL8:17 pmLambert-St Louis
19h 42m
1 stop
DCA4:59 pmWashington, D.C. Reagan-National
May 11
DCA7:00 amWashington, D.C. Reagan-National
13h 23m
1 stop
STL7:23 pmLambert-St Louis
$279
Frontier
May 22
STL8:08 pmLambert-St Louis
19h 51m
1 stop
DCA4:59 pmWashington, D.C. Reagan-National
May 24
DCA7:00 amWashington, D.C. Reagan-National
13h 23m
1 stop
STL7:23 pmLambert-St Louis
$309

American Airlines flights from St. Louis to Washington, D.C. Reagan-National Airport

Our best American Airlines deals on St. Louis to Washington, D.C. Reagan-National Airport flight tickets
American Airlines
May 27
STL5:08 amLambert-St Louis
2h 20m
DCA8:28 amWashington, D.C. Reagan-National
Jun 1
DCA3:52 pmWashington, D.C. Reagan-National
5h 38m
1 stop
STL8:30 pmLambert-St Louis
$261
American Airlines
Jun 12
STL5:03 pmLambert-St Louis
2h 13m
DCA8:16 pmWashington, D.C. Reagan-National
Jun 16
DCA8:40 amWashington, D.C. Reagan-National
2h 32m
STL10:12 amLambert-St Louis
$287
American Airlines
Jul 1
STL10:45 amLambert-St Louis
2h 14m
DCA1:59 pmWashington, D.C. Reagan-National
Jul 31
DCA8:35 amWashington, D.C. Reagan-National
2h 26m
STL10:01 amLambert-St Louis
$288

momondo Fare Finder

 
Customize your flight search to find flights from St. Louis to Washington, D.C. Reagan-National Airport 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, momondo users made 832,500 searches. Data last updated May 1, 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 5/27

5:08 am-8:28 am

Nonstop2h 20m

Washington, D.C. Reagan-National

Mon 6/1

8:00 pm-9:29 pm

Nonstop2h 29m

$251

St. LouisWashington, D.C.

STL - DCA

STLDCA

Lambert-St Louis

Tue 5/19

1:45 pm-7:10 pm

1 stop4h 25m

Washington, D.C. Reagan-National

Tue 6/9

11:45 am-2:50 pm

1 stop4h 05m

$252

St. LouisWashington, D.C.

STL - DCA

STLDCA

Lambert-St Louis

Tue 5/19

7:45 am-2:14 pm

1 stop5h 29m

Washington, D.C. Reagan-National

Wed 6/3

11:57 am-3:46 pm

1 stop4h 49m

$257

St. LouisWashington, D.C.

STL - DCA

STLDCA

Lambert-St Louis

Wed 5/27

5:08 am-8:28 am

Nonstop2h 20m

Washington, D.C. Reagan-National

Mon 6/1

3:52 pm-8:30 pm

1 stop5h 38m

$261

St. LouisWashington, D.C.

STL - DCA

STLDCA

Lambert-St Louis

Sat 5/23

6:00 am-9:19 am

Nonstop2h 19m

Washington, D.C. Reagan-National

Mon 5/25

8:40 am-10:12 am

Nonstop2h 32m

$265

St. LouisWashington, D.C.

STL - DCA

STLDCA

Lambert-St Louis

Sat 5/30

10:55 am-6:55 pm

2 stops7h 00m

Washington, D.C. Reagan-National

Tue 6/2

6:50 pm-8:15 pm

Nonstop2h 25m

$266

St. LouisWashington, D.C.

STL - DCA

STLDCA

Lambert-St Louis

Wed 5/27

1:59 pm-6:59 pm

1 stop4h 00m

Washington, D.C. Reagan-National

Thu 6/4

6:05 am-9:29 am

1 stop4h 24m

$271

St. LouisWashington, D.C.

STL - DCA

STLDCA

Lambert-St Louis

Tue 5/26

7:55 pm-11:00 pm

Nonstop2h 05m

Washington, D.C. Reagan-National

Sat 5/30

12:00 pm-1:25 pm

Nonstop2h 25m

$273

St. LouisWashington, D.C.

STL - DCA

STLDCA

Lambert-St Louis

Thu 5/28

5:40 am-11:10 am

1 stop4h 30m

Washington, D.C. Reagan-National

Thu 6/4

8:00 am-9:10 am

Nonstop2h 10m

$275
Quickest round-trip

St. LouisWashington, D.C.

STL - DCA

STLDCA

Lambert-St Louis

Tue 5/26

7:55 pm-11:00 pm

Nonstop2h 05m

Washington, D.C. Reagan-National

Fri 5/29

8:00 am-9:20 am

Nonstop2h 20m

$276

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 20 resultsSorted by cheapest first
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See travel insights to Washington, D.C. from

How to get the cheapest flight ticket from St. Louis to Washington, D.C. Reagan-National Airport

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

What is the typical price of a round-trip flight between St. Louis and Washington, D.C. Reagan-National Airport?

What is the cheapest month to fly to Washington, D.C. Reagan-National Airport?

The month of August is, on average, the cheapest month to fly to Washington, D.C. Reagan-National Airport from St. Louis, with most prices found around $253. If you aren’t able to travel to Washington, D.C. Reagan-National Airport during the month of August, then flying in September is also cheap. Prices for this month can be found on momondo for an average of $277.

What is the cheapest day to depart on your flight to Washington, D.C. Reagan-National Airport?

The cheapest day to depart from St. Louis to Washington, D.C. Reagan-National Airport is on a Saturday. Travelers who choose to depart for Washington, D.C. Reagan-National Airport on a Saturday will often find tickets for as low as $308. Flights from St. Louis to Washington, D.C. Reagan-National Airport on a Monday will generally be more expensive and average around $387. Keep in mind that these prices on both days could fluctuate depending on the season and the demand.

What is the cheapest time of day to depart on your flight to Washington, D.C. Reagan-National Airport?

Our data shows that the cheapest St. Louis to Washington, D.C. Reagan-National Airport flights are usually those with departure times at noon. Our users have found flights to Washington, D.C. Reagan-National Airport at noon for as low as $332. In contrast, the most expensive time of day to depart to Washington, D.C. Reagan-National Airport is in the morning when prices are around $352.

What is the cheapest Lambert-St Louis to Washington, D.C. Reagan-National flight route?

Fly from Lambert-St Louis to Washington, D.C. Reagan-National for the best Lambert-St Louis - Washington, D.C. Reagan-National flight prices

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

You are more likely to see cheaper flights to Washington, D.C. Reagan-National Airport from St. Louis when booking weeks ahead of your departure date. In general, you can expect to find flights to Washington, D.C. Reagan-National Airport for around $347 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Washington, D.C. Reagan-National Airport from St. Louis for as low as $214 on momondo.

Can stopping save me money on St. Louis to Washington, D.C. Reagan-National Airport flights?

You could potentially save up to 18% on your flight if you consider stops on a St. Louis to Washington, D.C. Reagan-National Airport flight.

How have St. Louis to Washington, D.C. Reagan-National Airport flight prices changed over time?

As of May 2026, prices for St. Louis to Washington, D.C. Reagan-National Airport flights are approximately 38% more expensive when compared to flights at the same time last year.

When to book flights from St. Louis to Washington, D.C. Reagan-National Airport

Are you open to changing your travel dates? Check out the ideal times to fly from St. Louis to Washington, D.C. Reagan-National Airport according to our flight data. Find out which month and days have the cheapest flights.
Estimated round-trip price

Cheap St. Louis to Washington, D.C. Reagan-National Airport (STL to DCA) flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from St. Louis to Washington, D.C. Reagan-National Airport

Best Price Found

$198

Fastest flight time

1h 55m

Direct flights

Every day
The best one-way flight to Washington, D.C. Reagan-National Airport from St. Louis in the past 72 hours is $198. The best round-trip flight deal from St. Louis to Washington, D.C. Reagan-National Airport found on momondo in the last 72 hours is $328.
The fastest flight from St. Louis to Washington, D.C. Reagan-National Airport takes 1h 55m
Direct flights go from St. Louis to Washington, D.C. Reagan-National Airport every day.

Frequently asked questions about flying from St. Louis to Washington, D.C. Reagan-National Airport

  • How far is Lambert-St Louis to Washington, D.C. Reagan-National by plane?

    Washington, D.C. Reagan-National is 708.3 mi away from Lambert-St Louis. In terms of flight time, this usually takes a little over 1h 55m.

  • When did momondo last update prices for flights from Lambert-St Louis Airport to Washington, D.C. Reagan-National Airport?

    Prices for flights from Lambert-St Louis Airport to Washington, D.C. Reagan-National Airport were last updated today.

  • How many operators does momondo search for flights from Lambert-St Louis Airport to Washington, D.C. Reagan-National Airport?

  • How old do you have to be to fly from Lambert-St Louis Airport to Washington, D.C. Reagan-National Airport?

    The minimum age for a child to fly alone is five, but airlines offering an unaccompanied minor (UNMR) service may have their age restrictions, such as regulations concerning flight duration, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Lambert-St Louis Airport to Washington, D.C. Reagan-National Airport.

  • What documentation or ID do you need to fly to Washington, D.C. Reagan-National Airport?

    The necessary travel and health documents for your Washington, D.C. Reagan-National Airport trip may vary depending on your travel plans and individual circumstances. Generally, you should have various documents, such as a national ID card or driver's license and a passport that is valid for six months beyond your scheduled arrival date. We recommend seeking advice from your airline or a trusted third party, such as IATA.

  • What is the most popular plane model from St. Louis to Washington, D.C. Reagan-National Airport?

  • What is the most popular airline from St. Louis to Washington, D.C. Reagan-National Airport?

Best airlines flying from St. Louis to Washington, D.C. Reagan-National Airport

Compare and see reviews for airlines that fly from St. Louis to Washington, D.C. Reagan-National Airport with momondo
Airline
Rating
Free Cancellation
Price
FrontierPriceFrom $96Free CancellationRating
5.6
2,972 reviews
Search Frontier flights
American AirlinesPriceFrom $172Free CancellationRating
7.1
11,678 reviews
Search American Airlines flights
SouthwestPriceFrom $197Free CancellationRating
8.0
4,315 reviews
Search Southwest flights
  • Southwest Flights From St. Louis to Washington, D.C. Reagan-National Airport

    The lowest priced Southwest flight from St. Louis to Washington, D.C. Reagan-National Airport from the last 72 hours was $197. Generally, Southwest has 19 flights on this route every week with an average price of $346. Southwest is rated 8.0/10 by our users.

  • American Airlines Flights From St. Louis to Washington, D.C. Reagan-National Airport

    The best American Airlines deal for St. Louis to Washington, D.C. Reagan-National Airport flight tickets found on momondo in the last 72 hours was $172, round-trip. It should be noted that an average American Airlines flight deal for this route in this time was higher, at $313 round-trip. American Airlines operates 15 flights out of St. Louis into Washington, D.C. Reagan-National Airport in an average week, so prices vary by time and availability. 11,678 American Airlines reviews by users on momondo have scored the airline at 7.1/10.

Traveling to a place near Washington, D.C.?

Book flights to Washington, D.C. if you plan to visit one of these locations
Alexandria
National Harbor
Gettysburg
Arlington
Waldorf
Woodbridge
Laurel
Colonial Beach
Gaithersburg
Towson
Fredericksburg
Silver Spring
Rockville
Manassas
Linthicum Heights
Tysons
Bethesda
Springfield
Fairfax
College Park

Why use momondo?

Why should I use momondo to find a flight deal from St. Louis to Washington, D.C.?

momondo compares prices from hundreds of airlines and agents so you can find and book the best deal on flights from St. Louis to Washington, D.C.. Millions of users trust and use momondo every year so you are in good hands.

Can I find flights from St. Louis to Washington, D.C. with flexible booking policies on momondo?

Yes. momondo enables you to select and highlight flights to Washington, D.C. from St. Louis with this policy.

How can momondo help me find flights from St. Louis to Washington, D.C.?

Once you have performed a search in the form on the page, momondo provides useful filters and insights. We can show you the cheapest days and times to fly as well as help filter your options to help you make an informed choice when booking flights to Washington, D.C. from St. Louis.

I’m not ready to book a flight from St. Louis to Washington, D.C. right now. Can momondo alert me if prices change?

Price alerts on flights to Washington, D.C. from St. Louis are quick and easy to set up on momondo. Simply perform a search and select the price alert feature. It is as simple as that.

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1 adult
Sun 5/31
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