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Cheap flights from St. Louis to Washington, D.C. from $78

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 10/14. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
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Cheap round-trip flights

American Airlines Logo
6:00 pm - 9:00 pmSTL-DCA
2h 00mnonstop
American Airlines Logo
7:59 pm - 9:19 pmDCA-STL
2h 20mnonstop
$157American Airlines
Find Deal
Wed, Sep 24 - Mon, Sep 29
Southwest Logo
8:00 am - 2:40 pmSTL-DCA
5h 40m1 stop
Southwest Logo
6:50 pm - 8:00 pmDCA-STL
2h 10mnonstop
$167Southwest
Find Deal
Thu, Aug 7 - Mon, Aug 11
Southwest Logo
9:50 am - 6:10 pmSTL-DCA
7h 20m2 stops
Southwest Logo
12:00 pm - 1:10 pmDCA-STL
2h 10mnonstop
$172Southwest
Find Deal
Thu, Sep 4 - Mon, Sep 8
American Airlines Logo
6:33 am - 9:29 amSTL-DCA
1h 56mnonstop
American Airlines Logo
7:58 am - 9:29 amDCA-STL
2h 31mnonstop
$178American Airlines
Find Deal
Wed, Nov 5 - Sat, Nov 8
Delta Logo
3:30 pm - 9:14 pmSTL-DCA
4h 44m1 stop
Delta Logo
11:00 am - 4:00 pmDCA-STL
6h 00m1 stop
$197Delta
Find Deal
Wed, Sep 24 - Mon, Sep 29
Delta Logo
1:30 pm - 8:46 pmSTL-DCA
6h 16m1 stop
Delta Logo
7:00 am - 12:35 pmDCA-STL
6h 35m1 stop
$199Delta
Find Deal
Tue, Jul 1 - Sat, Jul 5
United Airlines Logo
5:30 pm - 10:42 pmSTL-DCA
4h 12m1 stop
United Airlines Logo
7:25 am - 12:27 pmDCA-STL
6h 02m1 stop
$213United Airlines
Find Deal
Fri, Aug 1 - Thu, Aug 7
United Airlines Logo
5:30 pm - 10:43 pmSTL-DCA
4h 13m1 stop
United Airlines Logo
10:30 am - 3:44 pmDCA-STL
6h 14m1 stop
$226United Airlines
Find Deal
Sat, Aug 30 - Mon, Sep 1
Frontier Logo
7:29 pm - 4:59 pmSTL-DCA
20h 30m1 stop
Frontier Logo
1:00 pm - 9:11 amDCA-STL
21h 11m1 stop
$261Frontier
Find Deal
Fri, Aug 1 - Fri, Aug 8
Frontier Logo
7:29 pm - 4:59 pmSTL-DCA
20h 30m1 stop
Frontier Logo
6:00 pm - 9:11 amDCA-STL
16h 11m1 stop
$270Frontier
Find Deal
Wed, Jul 23 - Sun, Jul 27

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
Aug 1
STL7:29 pmLambert-St Louis
20h 30m
1 stop
DCA4:59 pmWashington, D.C. Reagan-National
Aug 8
DCA1:00 pmWashington, D.C. Reagan-National
21h 11m
1 stop
STL9:11 amLambert-St Louis
Frontier
Jul 23
STL7:29 pmLambert-St Louis
20h 30m
1 stop
DCA4:59 pmWashington, D.C. Reagan-National
Jul 27
DCA6:00 pmWashington, D.C. Reagan-National
16h 11m
1 stop
STL9:11 amLambert-St Louis
Frontier
Aug 1
STL7:29 pmLambert-St Louis
15h 35m
1 stop
DCA12:04 pmWashington, D.C. Reagan-National
Aug 8
DCA7:00 amWashington, D.C. Reagan-National
27h 11m
1 stop
STL9:11 amLambert-St Louis

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

Our best Delta deals on St. Louis to Washington, D.C. Reagan-National Airport flight tickets
Delta
Sep 24
STL3:30 pmLambert-St Louis
4h 44m
1 stop
DCA9:14 pmWashington, D.C. Reagan-National
Sep 29
DCA11:00 amWashington, D.C. Reagan-National
6h 00m
1 stop
STL4:00 pmLambert-St Louis
Delta
Jul 1
STL1:30 pmLambert-St Louis
6h 16m
1 stop
DCA8:46 pmWashington, D.C. Reagan-National
Jul 5
DCA7:00 amWashington, D.C. Reagan-National
6h 35m
1 stop
STL12:35 pmLambert-St Louis
Delta
Oct 3
STL5:40 pmLambert-St Louis
4h 39m
1 stop
DCA11:19 pmWashington, D.C. Reagan-National
Oct 7
DCA7:00 amWashington, D.C. Reagan-National
6h 25m
1 stop
STL12:25 pmLambert-St Louis

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 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 $259. 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 $268.

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 $306. Flights from St. Louis to Washington, D.C. Reagan-National Airport on a Sunday will generally be more expensive and average around $391. 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 in the evening. Our users have found flights to Washington, D.C. Reagan-National Airport in the evening for as low as $285. 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 $340.

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 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 16 weeks ahead of your departure date. In general, you can expect to find flights to Washington, D.C. Reagan-National Airport for around $292 when searching 16 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 $212 on momondo.

What cabin class options are available on Lambert-St Louis to Washington, D.C. Reagan-National flights?

There are 2 cabin classes available to choose from on Lambert-St Louis to Washington, D.C. Reagan-National flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

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

As of June 2025, prices for St. Louis to Washington, D.C. Reagan-National Airport flights are approximately 23% cheaper 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

$78

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 $78. 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 $157.
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.

  • 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 56m.

  • 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
American AirlinesPriceFrom $169Free CancellationRating
7.2
10,000 reviews
Search American Airlines flights
SouthwestPriceFrom $203Free CancellationRating
8.0
4,287 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 $203. Generally, Southwest has 26 flights on this route every week with an average price of $299. 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 $169, round-trip. It should be noted that an average American Airlines flight deal for this route in this time was higher, at $288 round-trip. American Airlines operates 16 flights out of St. Louis into Washington, D.C. Reagan-National Airport in an average week, so prices vary by time and availability. 10,000 American Airlines reviews by users on momondo have scored the airline at 7.2/10.


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

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

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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Tue 6/17
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