What airlines fly to Washington, D.C.?

American Airlines, Southwest and United Airlines are the top three most popular airlines that fly to Washington, D.C. from St. Louis according to our data. American Airlines is the first choice among our users, with 40% of people opting to fly with this airline when traveling to Washington, D.C.. Keep in mind that there are 5 different airlines that fly to Washington, D.C. on a routine basis, so you have a few additional options to choose from.

How many flights depart from St. Louis to Washington, D.C. on average per week?

The number of flights available between St. Louis and Washington, D.C. is 116 per week as of July 2025. The most frequent departure day is Mon, with 19% of weekly flights leaving on this day.

What is the cheapest airline that flies from Lambert-St Louis to Washington, D.C.?

Southwest, American Airlines, and Spirit Airlines are the most popular carriers operating from Lambert-St Louis to Washington, D.C.

How many flights depart from St. Louis to Washington, D.C. on average per day?

The number of flights available between St. Louis and Washington, D.C. is 16 per day as of July 2025. The most frequent departure time is 8:00AM, with 53% of daily flights leaving at noon.

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.?

The number of operators available for flights from Lambert-St Louis Airport to Washington, D.C. is 5 as of July 2025.

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.

$53 Cheap Flights from St. Louis to Washington, D.C. in 2025

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

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One-way

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Direct

Cheap round-trip flights

8:30 am - 11:30 amSTL-DCA

2h 00mnonstop

12:00 pm - 1:10 pmDCA-STL

2h 10mnonstop

$105Southwest

Find Deal

sáb., ago. 9 - mar., ago. 12

8:30 am - 11:30 amSTL-DCA

2h 00mnonstop

9:00 am - 2:25 pmDCA-STL

6h 25m1 stop

$115Southwest

Find Deal

sáb., ago. 9 - mar., ago. 12

6:00 am - 9:03 amSTL-DCA

2h 03mnonstop

7:53 pm - 9:20 pmDCA-STL

2h 27mnonstop

$129American Airlines

Find Deal

jue., oct. 2 - lun., oct. 6

5:52 pm - 8:53 pmSTL-DCA

2h 01mnonstop

7:51 pm - 9:02 pmDCA-STL

2h 11mnonstop

$149American Airlines

Find Deal

vie., ago. 29 - lun., sep. 1

1:04 pm - 4:12 pmSTL-IAD

2h 08mnonstop

6:35 am - 12:27 pmIAD-STL

6h 52m1 stop

$159United Airlines

Find Deal

mar., ago. 5 - mar., ago. 12

2:52 pm - 11:55 pmSTL-BWI

8h 03m1 stop

7:20 am - 1:59 pmBWI-STL

7h 39m1 stop

$168Frontier

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sáb., jul. 26 - sáb., ago. 2

1:04 pm - 4:12 pmSTL-IAD

2h 08mnonstop

8:40 am - 10:02 amIAD-STL

2h 22mnonstop

$170United Airlines

Find Deal

mar., ago. 5 - mar., ago. 26

2:52 pm - 11:55 pmSTL-BWI

8h 03m1 stop

7:20 am - 1:59 pmBWI-STL

7h 39m1 stop

$170Frontier

Find Deal

sáb., jul. 26 - sáb., ago. 2

1:26 pm - 9:44 pmSTL-DCA

7h 18m1 stop

6:00 am - 9:59 amDCA-STL

4h 59m1 stop

$197Delta

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lun., sep. 15 - jue., sep. 25

6:00 am - 12:33 pmSTL-BWI

5h 33m1 stop

6:00 am - 9:35 amBWI-STL

4h 35m1 stop

$197Delta

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jue., nov. 6 - jue., nov. 13

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

Aug 5

STL1:04 pmLambert-St Louis

2h 08m

IAD4:12 pmWashington, D.C. Dulles Intl

Aug 12

IAD6:35 amWashington, D.C. Dulles Intl

6h 52m

1 stop

STL12:27 pmLambert-St Louis

$159

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United Airlines

Aug 5

STL1:04 pmLambert-St Louis

2h 08m

IAD4:12 pmWashington, D.C. Dulles Intl

Aug 26

IAD8:40 amWashington, D.C. Dulles Intl

2h 22m

STL10:02 amLambert-St Louis

$170

Find similar

United Airlines

Sep 12

STL5:30 pmLambert-St Louis

6h 02m

1 stop

IAD12:32 amWashington, D.C. Dulles Intl

Sep 13

IAD8:40 amWashington, D.C. Dulles Intl

2h 22m

STL10:02 amLambert-St Louis

$173

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

Our best Delta deals on St. Louis to Washington, D.C. flight tickets

Delta

Oct 2

STL9:19 amLambert-St Louis

6h 08m

1 stop

IAD4:27 pmWashington, D.C. Dulles Intl

Oct 6

IAD7:50 pmWashington, D.C. Dulles Intl

4h 49m

1 stop

STL11:39 pmLambert-St Louis

$197

Find similar

Delta

Aug 5

STL6:04 pmLambert-St Louis

3h 51m

1 stop

IAD10:55 pmWashington, D.C. Dulles Intl

Aug 9

IAD6:00 amWashington, D.C. Dulles Intl

4h 33m

1 stop

STL9:33 amLambert-St Louis

$224

Find similar

Delta

Jul 23

STL6:40 amLambert-St Louis

3h 52m

1 stop

IAD11:32 amWashington, D.C. Dulles Intl

Jul 30

IAD6:00 amWashington, D.C. Dulles Intl

4h 41m

1 stop

STL9:41 amLambert-St Louis

$319

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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

Prices

Airlines

Other information

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 $229. 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 $231.

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 $364. However, this price may fluctuate depending on the airline, the season, and holidays. When flying out on a Saturday, the most expensive travel day of the week, you can expect to see flight prices from St. Louis to Washington, D.C. for around $482.

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 $995. 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 weeks ahead of your departure date. In general, you can expect to find flights to Washington, D.C. for around $376 when searching 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 $249 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.

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

No. A direct flight is the cheapest option for a flight between St. Louis to Washington, D.C..

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

As of July 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	$53
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 $53. The best round-trip flight deal from St. Louis to Washington, D.C. found on momondo in the last 72 hours is $105.

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)

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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.?
The number of operators available for flights from Lambert-St Louis Airport to Washington, D.C. is 5 as of July 2025.
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.?
Based on momondo bookings for this flight route, the most popular plane model on flight routes from St. Louis to Washington, D.C. is Boeing 737 MAX 8 (17.63% of total bookings). The next most popular plane models are Boeing 737-700 Passenger/BBJ1 (winglets) (17.21%), Boeing 737-800 Passenger/BBJ2 (winglets) (16.79%), and Canadair (Bombardier) Regional Jet 700 (13.79%).
What is the most popular airline from St. Louis to Washington, D.C.?
Based on momondo bookings for flights between St. Louis and Washington, D.C., the leading airline is Southwest, making up 50% of the total bookings. Other popular airlines include American Airlines with 40%, United Airlines with 6%, and Frontier with 2%.

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
Frontier	PriceFrom $120	Free Cancellation	Rating 5.9 3,271 reviews	Search Frontier flights
American Airlines	PriceFrom $129	Free Cancellation	Rating 7.2 10,000 reviews	Search American Airlines flights
Delta	PriceFrom $176	Free Cancellation	Rating 8.0 7,952 reviews	Search Delta flights
Southwest	PriceFrom $201	Free Cancellation	Rating 8.0 4,250 reviews	Search Southwest flights
United Airlines	PriceFrom $209	Free Cancellation	Rating 7.4 8,846 reviews	Search United Airlines flights

Southwest Flights From St. Louis to Washington, D.C.
Southwest operates around 26 flights from St. Louis to Washington, D.C. every week. The average price of these flights found in the last 72 hours has been $335, but momondo users have found Southwest deals from St. Louis to Washington, D.C. from as low as $201 round-trip. Southwest has been scored 8.0/10 in 4,249 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 $209, round-trip. It should be noted that an average United Airlines flight deal for this route in this time was higher, at $406 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. 8,846 United Airlines reviews by users on momondo have scored the airline at 7.4/10.

Alexandria

Gettysburg

Arlington

National Harbor

Laurel

Woodbridge

Tysons

Silver Spring

Waldorf

Fredericksburg

Manassas

Gaithersburg

Rockville

Towson

Fairfax

Colonial Beach

Glen Burnie

Linthicum Heights

Reston

Springfield

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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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Cheap flights from St. Louis to Washington, D.C. from $53

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 11/11. 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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United Airlines flights from St. Louis to Washington, D.C.

Our best United Airlines deals on St. Louis to Washington, D.C. flight tickets

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

Our best Delta deals on St. Louis to Washington, D.C. flight tickets

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.?

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

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

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.?

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.

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

No. A direct flight is the cheapest option for a flight between St. Louis to Washington, D.C..

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

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

What is the cheapest airline that flies from Lambert-St Louis to Washington, D.C.?

Southwest, American Airlines, and Spirit Airlines are the most popular carriers operating from Lambert-St Louis to Washington, D.C.

What airlines fly to Washington, D.C.?

How many flights depart from St. Louis to Washington, D.C. on average per day?

The number of flights available between St. Louis and Washington, D.C. is 16 per day as of July 2025. The most frequent departure time is 8:00AM, with 53% of daily flights leaving at noon.

How many flights depart from St. Louis to Washington, D.C. on average per week?

The number of flights available between St. Louis and Washington, D.C. is 116 per week as of July 2025. The most frequent departure day is Mon, with 19% of weekly flights leaving on this day.

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

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

Fastest flight time

Direct flights

Airports in Washington, D.C.

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

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

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.?

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

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

Southwest Flights From St. Louis to Washington, D.C.

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

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

Why use momondo?

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

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

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

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

An easier way to manage your Washington, D.C. trip

We make it super easy to schedule, organize and travel with friends or family. Trips is free — and available to use no matter where you book.

Get notified when prices go down

Daily price changes in your inbox - only with Price Alerts.

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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.