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Cheap flights from St. Louis to Washington, D.C. from $55

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 4/29. 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

These are some of the best round-trip flight deals from St. Louis to Washington, D.C. that have been recently found on momondo from popular airlines, departing in the coming months.
5:24 pm - 3:22 pmSTL-BWI
20h 58m1 stop
8:21 am - 11:46 pmBWI-STL
16h 25m1 stop
$115Frontier
Find Deal
Tue, Mar 25 - Wed, Apr 2
4:57 pm - 4:56 pmSTL-IAD
22h 59m1 stop
5:54 pm - 11:46 pmIAD-STL
6h 52m1 stop
$119Frontier
Find Deal
Wed, Apr 2 - Mon, Apr 7
8:49 am - 4:03 pmSTL-BWI
6h 14m1 stop
5:00 am - 8:09 amBWI-STL
4h 09m1 stop
$159American Airlines
Find Deal
Tue, Mar 25 - Sat, Mar 29
4:26 pm - 9:46 pmSTL-BWI
4h 20m1 stop
8:12 pm - 11:56 pmBWI-STL
4h 44m1 stop
$188American Airlines
Find Deal
Tue, Mar 18 - Tue, Mar 25
8:20 am - 12:40 pmSTL-BWI
3h 20m1 stop
8:30 pm - 9:55 pmBWI-STL
2h 25mnonstop
$193Southwest
Find Deal
Wed, Mar 26 - Tue, Apr 1
3:36 pm - 10:49 pmSTL-DCA
6h 13m1 stop
11:00 am - 2:49 pmDCA-STL
4h 49m1 stop
$197Delta
Find Deal
Tue, Mar 18 - Wed, Mar 26
6:50 am - 11:33 amSTL-BWI
3h 43m1 stop
6:00 am - 12:00 pmBWI-STL
7h 00m1 stop
$197Delta
Find Deal
Tue, Mar 18 - Wed, Mar 26
6:25 am - 1:00 pmSTL-BWI
5h 35m1 stop
6:15 am - 7:30 amBWI-STL
2h 15mnonstop
$207Southwest
Find Deal
Tue, May 13 - Mon, May 19
8:25 am - 11:39 amSTL-IAD
2h 14mnonstop
8:35 am - 10:08 amIAD-STL
2h 33mnonstop
$229United Airlines
Find Deal
Mon, Mar 24 - Thu, Mar 27
8:00 am - 2:11 pmSTL-IAD
5h 11m1 stop
8:35 am - 9:58 amIAD-STL
2h 23mnonstop
$233United Airlines
Find Deal
Sat, Apr 5 - Tue, Apr 8

United Airlines flights from St. Louis to Washington, D.C.

Our best United Airlines deals on St. Louis to Washington, D.C. flight tickets
United Airlines
Mar 24
STL8:25 amLambert-St Louis
2h 14m
IAD11:39 amWashington, D.C. Dulles Intl
Mar 27
IAD8:35 amWashington, D.C. Dulles Intl
2h 33m
STL10:08 amLambert-St Louis
United Airlines
Apr 5
STL8:00 amLambert-St Louis
5h 11m
1 stop
IAD2:11 pmWashington, D.C. Dulles Intl
Apr 8
IAD8:35 amWashington, D.C. Dulles Intl
2h 23m
STL9:58 amLambert-St Louis
United Airlines
Mar 26
STL8:25 amLambert-St Louis
2h 14m
IAD11:39 amWashington, D.C. Dulles Intl
Apr 1
IAD6:30 amWashington, D.C. Dulles Intl
5h 33m
1 stop
STL11:03 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
Mar 25
STL5:24 pmLambert-St Louis
20h 58m
1 stop
BWI3:22 pmBaltimore/Washington
Apr 2
BWI8:21 amBaltimore/Washington
16h 25m
1 stop
STL11:46 pmLambert-St Louis
Frontier
Apr 2
STL4:57 pmLambert-St Louis
22h 59m
1 stop
IAD4:56 pmWashington, D.C. Dulles Intl
Apr 7
IAD5:54 pmWashington, D.C. Dulles Intl
6h 52m
1 stop
STL11:46 pmLambert-St Louis
Frontier
Mar 25
STL5:24 pmLambert-St Louis
22h 30m
1 stop
IAD4:54 pmWashington, D.C. Dulles Intl
Apr 2
IAD5:54 pmWashington, D.C. Dulles Intl
6h 52m
1 stop
STL11:46 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.

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 $239. 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 $254.

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 $359. 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 $525.

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 $283. 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 $1,045. 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 11 weeks ahead of your departure date. In general, you can expect to find flights to Washington, D.C. for around $378 when searching 11 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 $284 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 February 2025, prices for St. Louis to Washington, D.C. flights are approximately 10% more expensive 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

$55

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 $55. The best round-trip flight deal from St. Louis to Washington, D.C. found on momondo in the last 72 hours is $115.
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 55m.

  • 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 $98Free CancellationRating
6.0
3,355 reviews
Search Frontier flights
American AirlinesPriceFrom $129Free CancellationRating
7.2
10,000 reviews
Search American Airlines flights
DeltaPriceFrom $177Free CancellationRating
8.0
8,219 reviews
Search Delta flights
SouthwestPriceFrom $200Free CancellationRating
8.1
4,411 reviews
Search Southwest flights
United AirlinesPriceFrom $211Free CancellationRating
7.4
8,765 reviews
Search United Airlines flights
  • Southwest Flights From St. Louis to Washington, D.C.

    Southwest operates around 16 flights from St. Louis to Washington, D.C. every week. The average price of these flights found in the last 72 hours has been $345, but momondo users have found Southwest deals from St. Louis to Washington, D.C. from as low as $200 round-trip. Southwest has been scored 8.1/10 in 4,411 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 $375 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. 8,766 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
Laurel
National Harbor
Silver Spring
Woodbridge
Fredericksburg
Manassas
Tysons
Waldorf
Gaithersburg
Linthicum Heights
Glen Burnie
Rockville
Fairfax
Towson
Hanover
Reston
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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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.