Latest deals
Insights
When to book
FAQs
Reviews
Price Alerts

Cheap flights from Washington, D.C. to St. Louis 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 Washington, D.C. to St. Louis departing on 12/4. 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

Discover deals from 900+ travel sites with momondo.

Save money when you book flights with momondo

Big names and deals

Big names and deals

Search 100s of travel sites to compare prices.

Filter for what you want

Filter for what you want

Free Wi-Fi? Stopover? Instantly customize your results.

Trusted and free

Trusted and free

We’re completely free to use - no hidden charges or fees.

Price Alerts

Price Alerts

Not ready to book? to track prices.
Search flight deals

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

Cheap round-trip flights

Enter your travel dates to find the best prices.
Frontier Logo
8:21 pm - 4:20 pmBWI-STL
20h 59m1 stop
Frontier Logo
10:25 am - 10:20 amSTL-BWI
22h 55m1 stop
$150Frontier
Find Deal
Thu, Nov 13 - Mon, Nov 17
Multiple Airlines Logo
6:55 pm - 7:50 amBWI-STL
13h 55m2 stops
Multiple Airlines Logo
5:11 pm - 10:52 amSTL-BWI
16h 41m1 stop
$151Multiple Airlines
Find Deal
Thu, Jan 8 - Mon, Jan 12
Delta Logo
6:00 am - 10:45 amBWI-STL
5h 45m1 stop
Delta Logo
7:02 pm - 12:19 amSTL-BWI
4h 17m1 stop
$229Delta
Find Deal
Tue, Dec 2 - Sun, Dec 7
Southwest Logo
10:30 am - 5:00 pmBWI-STL
7h 30m2 stops
Southwest Logo
12:45 pm - 7:55 pmSTL-BWI
6h 10m2 stops
$239Southwest
Find Deal
Sat, Dec 6 - Tue, Dec 9
Southwest Logo
12:25 pm - 1:45 pmDCA-STL
2h 20mnonstop
Southwest Logo
1:10 pm - 4:10 pmSTL-DCA
2h 00mnonstop
$263Southwest
Find Deal
Tue, Dec 2 - Tue, Dec 9
United Airlines Logo
8:40 am - 10:07 amIAD-STL
2h 27mnonstop
United Airlines Logo
8:30 am - 11:40 amSTL-IAD
2h 10mnonstop
$263United Airlines
Find Deal
Sat, Dec 6 - Tue, Dec 9
American Airlines Logo
11:40 am - 1:13 pmDCA-STL
2h 33mnonstop
American Airlines Logo
2:11 pm - 5:19 pmSTL-DCA
2h 08mnonstop
$268American Airlines
Find Deal
Sat, Dec 6 - Thu, Dec 11
United Airlines Logo
8:20 am - 2:25 pmIAD-STL
7h 05m1 stop
United Airlines Logo
8:30 am - 11:40 amSTL-IAD
2h 10mnonstop
$273United Airlines
Find Deal
Tue, Dec 2 - Tue, Dec 9
Delta Logo
5:59 pm - 9:57 pmIAD-STL
4h 58m1 stop
Delta Logo
9:30 am - 5:00 pmSTL-IAD
6h 30m1 stop
$283Delta
Find Deal
Tue, Dec 2 - Tue, Dec 9
American Airlines Logo
9:15 pm - 10:44 pmDCA-STL
2h 29mnonstop
American Airlines Logo
6:02 am - 9:10 amSTL-DCA
2h 08mnonstop
$286American Airlines
Find Deal
Mon, Dec 22 - Sat, Dec 27

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

Our best Delta deals on Washington, D.C. to St. Louis flight tickets
Delta
Dec 2
BWI6:00 amBaltimore/Washington
5h 45m
1 stop
STL10:45 amLambert-St Louis
Dec 7
STL7:02 pmLambert-St Louis
4h 17m
1 stop
BWI12:19 amBaltimore/Washington
$229
Find similar
Delta
Dec 2
IAD5:59 pmWashington, D.C. Dulles Intl
4h 58m
1 stop
STL9:57 pmLambert-St Louis
Dec 9
STL9:30 amLambert-St Louis
6h 30m
1 stop
IAD5:00 pmWashington, D.C. Dulles Intl
$283
Find similar
Delta
Nov 27
IAD6:00 amWashington, D.C. Dulles Intl
4h 59m
1 stop
STL9:59 amLambert-St Louis
Dec 1
STL6:09 pmLambert-St Louis
3h 54m
1 stop
IAD11:03 pmWashington, D.C. Dulles Intl
$332
Find similar

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

Our best United Airlines deals on Washington, D.C. to St. Louis flight tickets
United Airlines
Dec 6
IAD8:40 amWashington, D.C. Dulles Intl
2h 27m
STL10:07 amLambert-St Louis
Dec 9
STL8:30 amLambert-St Louis
2h 10m
IAD11:40 amWashington, D.C. Dulles Intl
$263
Find similar
United Airlines
Dec 2
IAD8:20 amWashington, D.C. Dulles Intl
7h 05m
1 stop
STL2:25 pmLambert-St Louis
Dec 9
STL8:30 amLambert-St Louis
2h 10m
IAD11:40 amWashington, D.C. Dulles Intl
$273
Find similar
United Airlines
Dec 4
IAD8:40 amWashington, D.C. Dulles Intl
2h 27m
STL10:07 amLambert-St Louis
Dec 8
STL8:30 amLambert-St Louis
2h 10m
IAD11:40 amWashington, D.C. Dulles Intl
$299
Find similar

momondo Fare Finder

 
Customize your flight search to find flights from Washington, D.C. to St. Louis 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 November 3, 2025.
Use the filters below to find and compare flights from Washington, D.C. to St. Louis that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

BaltimoreSt. Louis

BWI - STL

BWISTL

Baltimore/Washington

Thu 11/13

8:21 pm-4:20 pm

1 stop20h 59m

Lambert-St Louis

Mon 11/17

10:25 am-10:20 am

1 stop22h 55m

$150

BaltimoreSt. Louis

BWI - STL

BWISTL

Baltimore/Washington

Thu 1/8

6:55 pm-7:50 am

2 stops13h 55m

Lambert-St Louis

Mon 1/12

5:11 pm-10:52 am

1 stop16h 41m

$151

BaltimoreSt. Louis

BWI - STL

BWISTL

Baltimore/Washington

Tue 12/2

6:00 am-10:45 am

1 stop5h 45m

Lambert-St Louis

Sun 12/7

7:02 pm-12:19 am

1 stop4h 17m

$229

BaltimoreSt. Louis

BWI - STL

BWISTL

Baltimore/Washington

Sat 12/6

10:30 am-5:00 pm

2 stops7h 30m

Lambert-St Louis

Tue 12/9

12:45 pm-7:55 pm

2 stops6h 10m

$239

Washington, D.C.St. Louis

DCA - STL

DCASTL

Washington, D.C. Reagan-National

Tue 12/2

12:25 pm-1:45 pm

Nonstop2h 20m

Lambert-St Louis

Tue 12/9

1:10 pm-4:10 pm

Nonstop2h 00m

$263

Washington, D.C.St. Louis

IAD - STL

IADSTL

Washington, D.C. Dulles Intl

Sat 12/6

8:40 am-10:07 am

Nonstop2h 27m

Lambert-St Louis

Tue 12/9

8:30 am-11:40 am

Nonstop2h 10m

$263

Washington, D.C.St. Louis

DCA - STL

DCASTL

Washington, D.C. Reagan-National

Sat 12/6

11:40 am-1:13 pm

Nonstop2h 33m

Lambert-St Louis

Thu 12/11

2:11 pm-5:19 pm

Nonstop2h 08m

$268

Washington, D.C.St. Louis

IAD - STL

IADSTL

Washington, D.C. Dulles Intl

Tue 12/2

8:20 am-2:25 pm

1 stop7h 05m

Lambert-St Louis

Tue 12/9

8:30 am-11:40 am

Nonstop2h 10m

$273

Washington, D.C.St. Louis

IAD - STL

IADSTL

Washington, D.C. Dulles Intl

Tue 12/2

5:59 pm-9:57 pm

1 stop4h 58m

Lambert-St Louis

Tue 12/9

9:30 am-5:00 pm

1 stop6h 30m

$283

Washington, D.C.St. Louis

DCA - STL

DCASTL

Washington, D.C. Reagan-National

Mon 12/22

9:15 pm-10:44 pm

Nonstop2h 29m

Lambert-St Louis

Sat 12/27

6:02 am-9:10 am

Nonstop2h 08m

$286

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 20 resultsSorted by cheapest first
1
2

See travel insights to St. Louis from

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

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 Washington, D.C. and St. Louis?

What is the cheapest month to fly to St. Louis?

In general, August is the cheapest month to fly from Washington, D.C. to St. Louis. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $270. The month of September is another great option to travel to St. Louis, with average flight prices from Washington, D.C. averaging around $295.

What is the cheapest day to depart on your flight to St. Louis?

The cheapest day to depart on your flight to St. Louis is on a Tuesday when prices can be found for as low as $331. This is often the case because there is less demand to fly during this day of the week. If your travel schedule is flexible, try to avoid departing on a Sunday because tickets tend to average around $427. These prices are subject to change though, so be sure to set up a Price Alert for flights to St. Louis.

What is the cheapest time of day to depart on your flight to St. Louis?

Flying to St. Louis from Washington, D.C. in the evening is the least expensive time of day to depart. momondo users have found prices as low as $312 when looking at flights departing in the evening. In the afternoon is when there is more demand to fly to St. Louis, so prices are often more expensive at around $385 per ticket.

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

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

How far in advance should I book a flight to St. Louis?

You are more likely to see cheaper flights to St. Louis from Washington, D.C. when booking weeks ahead of your departure date. In general, you can expect to find flights to St. Louis for around $398 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to St. Louis from Washington, D.C. for as low as $260 on momondo.

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

There are 4 cabin classes available to choose from on Washington, D.C. to Lambert-St Louis 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 Washington, D.C. to St. Louis flights?

You could potentially save up to 20% on your flight if you consider stops on a Washington, D.C. to St. Louis flight.

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

As of November 2025, prices for Washington, D.C. to St. Louis flights are approximately 44% cheaper when compared to flights at the same time last year.

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

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

Cheap Washington, D.C. to St. Louis (WAS to STL) flight deals and tips

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

Best Price Found

$148

Fastest flight time

2h 20m

Direct flights

Every day

Airports in St. Louis

1 airport
The best one-way flight to St. Louis from Washington, D.C. in the past 72 hours is $148. The best round-trip flight deal from Washington, D.C. to St. Louis found on momondo in the last 72 hours is $311.
The fastest flight from Washington, D.C. to St. Louis takes 2h 20m
Direct flights go from Washington, D.C. to St. Louis every day.
There is 1 airport near St. Louis: Lambert-St Louis (STL)
Search flight deals

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

    There are 708.3 mi between Washington, D.C. and Lambert-St Louis. 2h 20m is a normal flight duration for this route.

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

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

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

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

  • What documentation or ID do you need to fly to Lambert-St Louis Airport?

    The required travel and health documents for your Lambert-St Louis Airport trip may vary depending on your itinerary and personal circumstances. As a general rule, you should carry multiple documents, including a national ID card or driver's license and a passport valid for six months after your intended arrival at Lambert-St Louis Airport. We recommend that you seek guidance from your airline or a reliable third party such as IATA.

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

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

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

Compare and see reviews for airlines that fly from Washington, D.C. to St. Louis with momondo
Airline
Rating
Free Cancellation
Price
FrontierPriceFrom $112Free CancellationRating
5.8
3,117 reviews
Search Frontier flights
DeltaPriceFrom $130Free CancellationRating
7.9
8,002 reviews
Search Delta flights
American AirlinesPriceFrom $172Free CancellationRating
7.2
11,038 reviews
Search American Airlines flights
SouthwestPriceFrom $188Free CancellationRating
8.0
4,238 reviews
Search Southwest flights
United AirlinesPriceFrom $223Free CancellationRating
7.4
8,997 reviews
Search United Airlines flights

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

    Southwest operates around 12 flights from Washington, D.C. to St. Louis every week. The average price of these flights found in the last 72 hours has been $349, but momondo users have found Southwest deals from Washington, D.C. to St. Louis from as low as $188 round-trip. Southwest has been scored 8.0/10 in 4,238 reviews.

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

    United Airlines (7.4/10 from 8,997 reviews) operates around 14 flights from Washington, D.C. to St. Louis in any given week. The average United Airlines airfare for this route is around $401, with deals from around $223 rare but found on momondo. Referenced prices are for round-trip Washington, D.C. to St. Louis flight searches in the last 72 hours.

Traveling to a place near St. Louis?

Book flights to St. Louis if you plan to visit one of these locations
St. Charles
Chesterfield
Hermann
Fairview Heights
Florissant
Maryland Heights
O'Fallon
Wentzville
Fenton
Collinsville
St. Peters
Alton
Farmington
Festus
Glencoe
Edwardsville
Clayton
Eureka
Litchfield
Shrewsbury

Why use momondo?

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

To find the flight that best suits your needs, momondo gathers a range of flights from a large pool of different airlines and agents; you can then use our insights and filters to find and book the right flight to St. Louis from Washington, D.C..

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

Yes. momondo allows you to filter the results for Washington, D.C. to St. Louis flights to just show those with flexible booking policies.

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

momondo helps you find the best flight between Washington, D.C. and St. Louis by providing filters to narrow your choice of flights to those matching your criteria. You can select flights based on numerous factors such as price, departure and landing times, airport and airline.

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

If you are simply researching potential flights to St. Louis, momondo offers a useful price alert feature which will track prices for flights to St. Louis from Washington, D.C. and alert you when they change.

An easier way to manage your St. Louis 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.
Start using Trips
Find my bookings

Get notified when prices go down

Daily price changes in your inbox - only with Price Alerts.
1 adult
Wed 12/3
Wed 12/10
By creating a price alert you accept our terms of use and privacy policy.

Find better results for your trip to the United States