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Cheap flights from St. Louis to Washington, D.C. from $90

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 5/24. 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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Find the cheapest flights from St. Louis to Washington, D.C.

Cheap round-trip flights

KAYAK's recommended round-trip deals from the most popular airlines that fly from St. Louis to Washington, D.C..
Southwest Logo
6:45 pm - 9:45 pmSTL-DCA
2h 00mnonstop
Southwest Logo
12:35 pm - 1:50 pmDCA-STL
2h 15mnonstop
$179Southwest
Find Deal
Sat, May 24 - Sun, May 25
Frontier Logo
5:45 pm - 2:55 pmSTL-BWI
20h 10m1 stop
Frontier Logo
9:21 pm - 12:06 amBWI-STL
27h 45m1 stop
$183Frontier
Find Deal
Tue, May 6 - Sat, May 10
Delta Logo
5:40 pm - 11:43 pmSTL-DCA
5h 03m1 stop
Delta Logo
6:34 pm - 11:38 pmDCA-STL
6h 04m1 stop
$199Delta
Find Deal
Sat, May 24 - Sun, May 25
Delta Logo
5:40 pm - 12:28 amSTL-IAD
5h 48m1 stop
Delta Logo
7:15 am - 11:54 amIAD-STL
5h 39m1 stop
$199Delta
Find Deal
Thu, May 29 - Sat, May 31
United Airlines Logo
8:15 am - 11:23 amSTL-IAD
2h 08mnonstop
United Airlines Logo
8:40 am - 9:59 amIAD-STL
2h 19mnonstop
$229United Airlines
Find Deal
Tue, Jul 29 - Sat, Aug 2
American Airlines Logo
10:25 am - 1:24 pmSTL-DCA
1h 59mnonstop
American Airlines Logo
6:05 am - 10:43 amDCA-STL
5h 38m1 stop
$238American Airlines
Find Deal
Thu, May 29 - Mon, Jun 2
United Airlines Logo
8:00 am - 1:49 pmSTL-IAD
4h 49m1 stop
United Airlines Logo
8:40 am - 9:59 amIAD-STL
2h 19mnonstop
$239United Airlines
Find Deal
Tue, Jul 29 - Sat, Aug 2
American Airlines Logo
7:58 am - 10:59 amSTL-DCA
2h 01mnonstop
American Airlines Logo
5:10 am - 8:14 amDCA-STL
4h 04m1 stop
$244American Airlines
Find Deal
Sun, Jun 29 - Wed, Jul 2
 Logo
12:15 pm - 1:19 pmSTL-BWI
24h 04m2 stops
 Logo
7:57 pm - 9:15 amBWI-STL
14h 18m1 stop
Wed, May 14 - Fri, May 16
 Logo
12:15 pm - 1:19 pmSTL-BWI
24h 04m2 stops
 Logo
12:51 pm - 9:15 amBWI-STL
21h 24m2 stops
Wed, May 14 - Fri, May 16

Delta flights from St. Louis to Washington, D.C.

Our best Delta deals on St. Louis to Washington, D.C. flight tickets
Delta
May 29
STL5:40 pmLambert-St Louis
5h 48m
1 stop
IAD12:28 amWashington, D.C. Dulles Intl
May 31
IAD7:15 amWashington, D.C. Dulles Intl
5h 39m
1 stop
STL11:54 amLambert-St Louis
Delta
May 24
STL5:17 pmLambert-St Louis
4h 37m
1 stop
IAD10:54 pmWashington, D.C. Dulles Intl
May 26
IAD6:00 amWashington, D.C. Dulles Intl
4h 00m
1 stop
STL9:00 amLambert-St Louis
Delta
Aug 27
STL6:45 amLambert-St Louis
4h 02m
1 stop
IAD11:47 amWashington, D.C. Dulles Intl
Sep 1
IAD6:10 amWashington, D.C. Dulles Intl
4h 19m
1 stop
STL9:29 amLambert-St Louis

Frontier flights from St. Louis to Washington, D.C.

Our best Frontier deals on St. Louis to Washington, D.C. flight tickets
Frontier
May 6
STL5:45 pmLambert-St Louis
20h 10m
1 stop
BWI2:55 pmBaltimore/Washington
May 10
BWI9:21 pmBaltimore/Washington
27h 45m
1 stop
STL12:06 amLambert-St Louis
Frontier
May 7
STL5:45 pmLambert-St Louis
24h 31m
1 stop
BWI7:16 pmBaltimore/Washington
May 14
BWI10:40 amBaltimore/Washington
14h 26m
1 stop
STL12:06 amLambert-St Louis
Frontier
May 14
STL5:45 pmLambert-St Louis
21h 51m
1 stop
IAD4:36 pmWashington, D.C. Dulles Intl
May 16
IAD5:26 pmWashington, D.C. Dulles Intl
7h 48m
1 stop
STL12:14 amLambert-St Louis

See travel insights to Washington, D.C. from

How to get the cheapest flight ticket from St. Louis to Washington, D.C.

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.?

The month of November is, on average, the cheapest month to fly to Washington, D.C. from St. Louis, with most prices found around $235. If you’re not able to fly to Washington, D.C. in November, then August is your next best option. Flight prices from St. Louis to Washington, D.C. during August average around $253.

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

On average, the least expensive day to fly to Washington, D.C. from St. Louis is on a Friday. momondo users have found tickets for Friday departures for as low as $361. However, this price may fluctuate depending on the airline, the season, and holidays. When flying out on a Sunday, the most expensive travel day of the week, you can expect to see flight prices from St. Louis to Washington, D.C. for around $543.

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

In the evening is the cheapest time of day to fly from St. Louis to Washington, D.C. when you can find flight prices for as low as $290. Flying to Washington, D.C. in the evening is an ideal time because this is during off-peak travel hours. Try not to purchase tickets at noon because they tend to be around $1,049. Of course, these prices can vary depending on the time of year and what airport you fly to.

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

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

How far in advance should I book a flight to Washington, D.C.?

You are more likely to see cheaper flights to Washington, D.C. from St. Louis when booking 23 weeks ahead of your departure date. In general, you can expect to find flights to Washington, D.C. for around $378 when searching 23 weeks out.However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Washington, D.C. from St. Louis for as low as $258 on momondo.

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

There are 4 cabin classes available to choose from on Lambert-St Louis to Washington, D.C. 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. flight prices changed over time?

As of April 2025, prices for St. Louis to Washington, D.C. flights are approximately 1% cheaper when compared to flights at the same time last year.

When to book flights from St. Louis to Washington, D.C.

Are you open to changing your travel dates? Check out the ideal times to fly from St. Louis to Washington, D.C. 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. (STL to WAS) flight deals and tips

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

Best Price Found

$90

Fastest flight time

1h 55m

Direct flights

Every day

Airports in Washington, D.C.

3 airports
The best one-way flight to Washington, D.C. from St. Louis in the past 72 hours is $90. The best round-trip flight deal from St. Louis to Washington, D.C. found on momondo in the last 72 hours is $179.
The fastest flight from St. Louis to Washington, D.C. takes 1h 55m
Direct flights go from St. Louis to Washington, D.C. every day.
There are 3 airports near Washington, D.C.: Washington, D.C. Reagan-National (DCA), Baltimore/Washington (BWI), Washington, D.C. Dulles Intl (IAD)

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

    A flight from Lambert-St Louis to Washington, D.C. will travel around 708.3 mi. By plane, this route typically takes 1h 58m.

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

    Prices for flights from Lambert-St Louis Airport to Washington, D.C. are updated daily.

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

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

    The minimum age for a child to fly alone is five, but airlines that offer an unaccompanied minor (UNMR) service may have their own age limitations. Flight duration, scheduling, and layovers are among the considerations that may influence age limits. We recommend that you double-check with the airline you are booking with for travel from Lambert-St Louis Airport to Washington, D.C..

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

    The travel and health documents required for your trip to Washington, D.C. can vary based on your itinerary and personal situation. As a rule, consider having multiple documents such as a national ID card or driver’s license, and a passport valid for six-months after you plan to arrive at Washington, D.C.. We always recommend checking with your airline or a trusted third party such as IATA to get advice.

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

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


Best airlines flying from St. Louis to Washington, D.C.

Compare and see reviews for airlines that fly from St. Louis to Washington, D.C. with momondo
Airline
Rating
Free Cancellation
Price
FrontierPriceFrom $108Free CancellationRating
5.9
3,283 reviews
Search Frontier flights
American AirlinesPriceFrom $129Free CancellationRating
7.2
10,000 reviews
Search American Airlines flights
DeltaPriceFrom $186Free CancellationRating
8.0
7,920 reviews
Search Delta flights
SouthwestPriceFrom $197Free CancellationRating
8.0
4,287 reviews
Search Southwest flights
United AirlinesPriceFrom $211Free CancellationRating
7.4
8,685 reviews
Search United Airlines flights
  • Southwest Flights From St. Louis to Washington, D.C.

    Southwest operates around 20 flights from St. Louis to Washington, D.C. every week. The average price of these flights found in the last 72 hours has been $340, but momondo users have found Southwest deals from St. Louis to Washington, D.C. from as low as $197 round-trip. Southwest has been scored 8.0/10 in 4,287 reviews.

  • United Airlines Flights From St. Louis to Washington, D.C.

    The best United Airlines deal for St. Louis to Washington, D.C. flight tickets found on momondo in the last 72 hours was $211, round-trip. It should be noted that an average United Airlines flight deal for this route in this time was higher, at $398 round-trip. United Airlines operates 14 flights out of St. Louis into Washington, D.C. in an average week, so prices vary by time and availability. 8,685 United Airlines reviews by users on momondo have scored the airline at 7.4/10.


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

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

Why use momondo?

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

momondo collates all your flight options in one place and lets you filter them to find the perfect flight from St. Louis to Washington, D.C.. momondo saves you time and could save you money on your trip.

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

Yes. All flights to Washington, D.C. from St. Louis on momondo can be compared and filtered by various policies on offer, including flexible booking.

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

momondo provides multiple filters to help you find the best flight to Washington, D.C. from St. Louis. Filter by price, airline, airports, cabin, aircraft, payment method, number of stops and more.

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

Of course. momondo tracks the price of St. Louis to Washington, D.C. flights. All you need is a valid email address and we will do the rest; it is that quick and easy.


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Mon 4/28
Mon 5/5

Find better results for your trip to the United States

Fly into one of these airports located in Washington, D.C.

Airports listed have a maximum distance of 22.4 mi from Washington, D.C.