Latest deals
Insights
When to book
FAQs
Reviews
Price Alerts

Cheap flights from Washington, D.C. to St. Louis from $66

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 10/21. 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

Frontier Logo
6:22 am - 3:04 pmBWI-STL
9h 42m1 stop
Frontier Logo
9:32 pm - 3:17 pmSTL-BWI
16h 45m1 stop
$143Frontier
Find Deal
Thu, Oct 2 - Fri, Oct 3
Frontier Logo
6:09 pm - 6:02 pmBWI-STL
24h 53m1 stop
Frontier Logo
6:05 pm - 10:20 amSTL-BWI
15h 15m1 stop
$144Frontier
Find Deal
Fri, Oct 17 - Mon, Oct 20
United Airlines Logo
6:29 am - 10:49 amBWI-STL
5h 20m1 stop
United Airlines Logo
3:23 pm - 9:22 pmSTL-BWI
4h 59m1 stop
$151United Airlines
Find Deal
Tue, Oct 21 - Tue, Oct 21
American Airlines Logo
6:13 pm - 11:54 pmBWI-STL
6h 41m1 stop
American Airlines Logo
4:25 pm - 9:54 pmSTL-BWI
4h 29m1 stop
$159American Airlines
Find Deal
Wed, Oct 8 - Sat, Oct 11
Delta Logo
6:00 am - 9:15 amBWI-STL
4h 15m1 stop
Delta Logo
9:10 am - 5:17 pmSTL-BWI
7h 07m1 stop
$197Delta
Find Deal
Sat, Oct 11 - Wed, Oct 15
American Airlines Logo
1:44 pm - 6:46 pmDCA-STL
6h 02m1 stop
American Airlines Logo
6:08 pm - 9:10 pmSTL-DCA
2h 02mnonstop
$204American Airlines
Find Deal
Tue, Oct 7 - Tue, Oct 14
United Airlines Logo
6:15 am - 10:51 amBWI-STL
5h 36m1 stop
United Airlines Logo
10:00 am - 5:14 pmSTL-BWI
6h 14m1 stop
$207United Airlines
Find Deal
Sat, Nov 22 - Mon, Nov 24
Southwest Logo
12:25 pm - 1:45 pmDCA-STL
2h 20mnonstop
Southwest Logo
3:30 pm - 6:25 pmSTL-DCA
1h 55mnonstop
$260Southwest
Find Deal
Wed, Nov 12 - Sat, Nov 15
Southwest Logo
6:45 pm - 8:10 pmDCA-STL
2h 25mnonstop
Southwest Logo
1:20 pm - 4:20 pmSTL-DCA
2h 00mnonstop
$263Southwest
Find Deal
Sat, Nov 22 - Mon, Nov 24
Delta Logo
6:00 am - 9:46 amIAD-STL
4h 46m1 stop
Delta Logo
6:00 am - 11:34 amSTL-IAD
4h 34m1 stop
$275Delta
Find Deal
Tue, Nov 25 - Fri, Nov 28

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

Our best Frontier deals on Washington, D.C. to St. Louis flight tickets
Frontier
Oct 2
BWI6:22 amBaltimore/Washington
9h 42m
1 stop
STL3:04 pmLambert-St Louis
Oct 3
STL9:32 pmLambert-St Louis
16h 45m
1 stop
BWI3:17 pmBaltimore/Washington
$143
Find similar
Frontier
Oct 17
BWI6:09 pmBaltimore/Washington
24h 53m
1 stop
STL6:02 pmLambert-St Louis
Oct 20
STL6:05 pmLambert-St Louis
15h 15m
1 stop
BWI10:20 amBaltimore/Washington
$144
Find similar
Frontier
Oct 9
BWI6:05 amBaltimore/Washington
5h 32m
1 stop
STL10:37 amLambert-St Louis
Oct 12
STL1:41 pmLambert-St Louis
17h 53m
1 stop
BWI8:34 amBaltimore/Washington
$157
Find similar

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

Our best American Airlines deals on Washington, D.C. to St. Louis flight tickets
American Airlines
Oct 8
BWI6:13 pmBaltimore/Washington
6h 41m
1 stop
STL11:54 pmLambert-St Louis
Oct 11
STL4:25 pmLambert-St Louis
4h 29m
1 stop
BWI9:54 pmBaltimore/Washington
$159
Find similar
American Airlines
Oct 7
DCA1:44 pmWashington, D.C. Reagan-National
6h 02m
1 stop
STL6:46 pmLambert-St Louis
Oct 14
STL6:08 pmLambert-St Louis
2h 02m
DCA9:10 pmWashington, D.C. Reagan-National
$204
Find similar
American Airlines
Oct 11
BWI5:00 amBaltimore/Washington
4h 16m
1 stop
STL8:16 amLambert-St Louis
Oct 15
STL5:23 amLambert-St Louis
12h 05m
1 stop
BWI6:28 pmBaltimore/Washington
$205
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 September 17, 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 10/2

6:22 am-3:04 pm

1 stop9h 42m

Lambert-St Louis

Fri 10/3

9:32 pm-3:17 pm

1 stop16h 45m

$143

BaltimoreSt. Louis

BWI - STL

BWISTL

Baltimore/Washington

Fri 10/17

6:09 pm-6:02 pm

1 stop24h 53m

Lambert-St Louis

Mon 10/20

6:05 pm-10:20 am

1 stop15h 15m

$144

BaltimoreSt. Louis

BWI - STL

BWISTL

Baltimore/Washington

Tue 10/21

6:29 am-10:49 am

1 stop5h 20m

Lambert-St Louis

Tue 10/21

3:23 pm-9:22 pm

1 stop4h 59m

$151

BaltimoreSt. Louis

BWI - STL

BWISTL

Baltimore/Washington

Wed 10/8

6:13 pm-11:54 pm

1 stop6h 41m

Lambert-St Louis

Sat 10/11

4:25 pm-9:54 pm

1 stop4h 29m

$159

BaltimoreSt. Louis

BWI - STL

BWISTL

Baltimore/Washington

Sat 10/11

6:00 am-9:15 am

1 stop4h 15m

Lambert-St Louis

Wed 10/15

9:10 am-5:17 pm

1 stop7h 07m

$197

Washington, D.C.St. Louis

DCA - STL

DCASTL

Washington, D.C. Reagan-National

Tue 10/7

1:44 pm-6:46 pm

1 stop6h 02m

Lambert-St Louis

Tue 10/14

6:08 pm-9:10 pm

Nonstop2h 02m

$204

BaltimoreSt. Louis

BWI - STL

BWISTL

Baltimore/Washington

Sat 11/22

6:15 am-10:51 am

1 stop5h 36m

Lambert-St Louis

Mon 11/24

10:00 am-5:14 pm

1 stop6h 14m

$207

Washington, D.C.St. Louis

DCA - STL

DCASTL

Washington, D.C. Reagan-National

Wed 11/12

12:25 pm-1:45 pm

Nonstop2h 20m

Lambert-St Louis

Sat 11/15

3:30 pm-6:25 pm

Nonstop1h 55m

$260

Washington, D.C.St. Louis

DCA - STL

DCASTL

Washington, D.C. Reagan-National

Sat 11/22

6:45 pm-8:10 pm

Nonstop2h 25m

Lambert-St Louis

Mon 11/24

1:20 pm-4:20 pm

Nonstop2h 00m

$263

Washington, D.C.St. Louis

IAD - STL

IADSTL

Washington, D.C. Dulles Intl

Tue 11/25

6:00 am-9:46 am

1 stop4h 46m

Lambert-St Louis

Fri 11/28

6:00 am-11:34 am

1 stop4h 34m

$275

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 $267. The month of May is another great option to travel to St. Louis, with average flight prices from Washington, D.C. averaging around $297.

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 Wednesday when prices can be found for as low as $350. 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 $411. 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. at noon is the least expensive time of day to depart. momondo users have found prices as low as $313 when looking at flights departing at noon. In the afternoon is when there is more demand to fly to St. Louis, so prices are often more expensive at around $383 per ticket.

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

Fly from Baltimore/Washington 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 $400 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 10% 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 September 2025, prices for Washington, D.C. to St. Louis flights are approximately 23% 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 10m

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 $284.
The fastest flight from Washington, D.C. to St. Louis takes 2h 10m
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 15m 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 $109Free CancellationRating
5.8
3,173 reviews
Search Frontier flights
American AirlinesPriceFrom $167Free CancellationRating
7.2
10,000 reviews
Search American Airlines flights
DeltaPriceFrom $169Free CancellationRating
7.9
7,961 reviews
Search Delta flights
SouthwestPriceFrom $188Free CancellationRating
8.0
4,242 reviews
Search Southwest flights
United AirlinesPriceFrom $271Free CancellationRating
7.4
8,926 reviews
Search United Airlines flights

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

    Southwest operates around 24 flights from Washington, D.C. to St. Louis every week. The average price of these flights found in the last 72 hours has been $342, 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 4,242 reviews.

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

    United Airlines (7.4/10 from 8,926 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 $478, with deals from around $271 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
Fenton
Collinsville
Wentzville
Alton
St. Peters
Farmington
Festus
Glencoe
Clayton
Edwardsville
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
Fri 10/17
Fri 10/24
By creating a price alert you accept our terms of use and privacy policy.

Find better results for your trip to the United States