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Cheap flights from Washington, D.C. to St. Louis from $51

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 4/1. 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 Washington, D.C. to St. Louis

Cheap round-trip flights

These are some of the best round-trip flight deals from Washington, D.C. to St. Louis that have been recently found on momondo from popular airlines, departing in the coming months.
3:53 pm - 11:46 pmBWI-STL
8h 53m1 stop
4:57 pm - 2:57 pmSTL-BWI
21h 00m1 stop
$110Frontier
Find Deal
Thu, Apr 3 - Mon, Apr 7
9:12 pm - 12:04 amBWI-STL
27h 52m1 stop
5:41 pm - 2:41 pmSTL-BWI
20h 00m1 stop
$120Frontier
Find Deal
Sat, Apr 26 - Tue, Apr 29
5:00 am - 8:30 amBWI-STL
4h 30m1 stop
10:17 am - 5:44 pmSTL-BWI
6h 27m1 stop
$178American Airlines
Find Deal
Mon, Apr 7 - Wed, Apr 9
6:05 am - 7:30 amBWI-STL
2h 25mnonstop
8:05 am - 12:25 pmSTL-BWI
3h 20m1 stop
$193Southwest
Find Deal
Mon, Apr 7 - Thu, Apr 10
9:05 pm - 10:29 pmDCA-STL
2h 24mnonstop
10:48 am - 1:50 pmSTL-DCA
2h 02mnonstop
$197American Airlines
Find Deal
Mon, Mar 31 - Fri, May 2
10:20 pm - 11:40 pmBWI-STL
2h 20mnonstop
9:10 am - 12:10 pmSTL-BWI
2h 00mnonstop
$197Southwest
Find Deal
Mon, Apr 7 - Wed, Apr 9
1:48 pm - 8:18 pmIAD-STL
7h 30m1 stop
7:10 pm - 12:28 amSTL-IAD
4h 18m1 stop
$217Delta
Find Deal
Fri, Mar 14 - Mon, Mar 17
7:35 am - 11:45 amIAD-STL
5h 10m1 stop
6:50 am - 11:31 amSTL-IAD
3h 41m1 stop
$237Delta
Find Deal
Sat, Apr 26 - Tue, Apr 29
8:15 am - 12:20 pmIAD-STL
5h 05m1 stop
8:25 am - 11:31 amSTL-IAD
2h 06mnonstop
$240United Airlines
Find Deal
Wed, Jul 2 - Sat, Jul 5
6:30 am - 10:45 amIAD-STL
5h 15m1 stop
8:10 am - 1:44 pmSTL-IAD
4h 34m1 stop
$250United Airlines
Find Deal
Wed, Jul 2 - Sat, Jul 5

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

Our best Frontier deals on Washington, D.C. to St. Louis flight tickets
Frontier
Apr 3
BWI3:53 pmBaltimore/Washington
8h 53m
1 stop
STL11:46 pmLambert-St Louis
Apr 7
STL4:57 pmLambert-St Louis
21h 00m
1 stop
BWI2:57 pmBaltimore/Washington
Frontier
Apr 26
BWI9:12 pmBaltimore/Washington
27h 52m
1 stop
STL12:04 amLambert-St Louis
Apr 29
STL5:41 pmLambert-St Louis
20h 00m
1 stop
BWI2:41 pmBaltimore/Washington
Frontier
Apr 9
BWI8:21 amBaltimore/Washington
16h 25m
1 stop
STL11:46 pmLambert-St Louis
Apr 13
STL4:57 pmLambert-St Louis
27h 09m
1 stop
BWI9:06 pmBaltimore/Washington

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

Our best Spirit Airlines deals on Washington, D.C. to St. Louis flight tickets
Spirit Airlines
Apr 21
BWI6:33 pmBaltimore/Washington
23h 43m
1 stop
STL5:16 pmLambert-St Louis
Apr 24
STL6:11 pmLambert-St Louis
5h 45m
1 stop
BWI12:56 amBaltimore/Washington
Spirit Airlines
Apr 24
BWI6:50 amBaltimore/Washington
11h 26m
1 stop
STL5:16 pmLambert-St Louis
Apr 27
STL6:11 pmLambert-St Louis
5h 45m
1 stop
BWI12:56 amBaltimore/Washington
Spirit Airlines
Apr 7
BWI6:05 amBaltimore/Washington
36h 47m
2 stops
STL5:52 pmLambert-St Louis
Apr 10
STL6:11 pmLambert-St Louis
5h 45m
1 stop
BWI12:56 amBaltimore/Washington

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 $289. The month of October is another great option to travel to St. Louis, with average flight prices from Washington, D.C. averaging around $299.

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 $349. 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 $402. 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 $307 when looking at flights departing in the evening. In the morning is when there is more demand to fly to St. Louis, so prices are often more expensive at around $403 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 18 weeks ahead of your departure date. In general, you can expect to find flights to St. Louis for around $433 when searching 18 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 $279 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.

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

As of February 2025, prices for Washington, D.C. to St. Louis flights are approximately 54% 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

$51

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 $51. The best round-trip flight deal from Washington, D.C. to St. Louis found on momondo in the last 72 hours is $110.
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)

  • 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 10m 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 $98Free CancellationRating
6.0
3,355 reviews
Search Frontier flights
Spirit AirlinesPriceFrom $133Free CancellationRating
6.3
8,013 reviews
Search Spirit Airlines flights
United AirlinesPriceFrom $158Free CancellationRating
7.4
8,765 reviews
Search United Airlines flights
DeltaPriceFrom $175Free CancellationRating
8.0
8,219 reviews
Search Delta flights
American AirlinesPriceFrom $183Free CancellationRating
7.2
10,000 reviews
Search American Airlines flights
SouthwestPriceFrom $219Free CancellationRating
8.1
4,411 reviews
Search Southwest flights
  • Southwest Flights From Washington, D.C. to St. Louis

    Southwest operates around 20 flights from Washington, D.C. to St. Louis every week. The average price of these flights found in the last 72 hours has been $364, but momondo users have found Southwest deals from Washington, D.C. to St. Louis from as low as $219 round-trip. Southwest has been scored 8.1/10 in 4,411 reviews.

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

    United Airlines (7.4/10 from 8,766 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 $399, with deals from around $158 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
Collinsville
Florissant
Maryland Heights
Hermann
Fairview Heights
Fenton
O'Fallon
Farmington
Alton
St. Peters
Wentzville
Eureka
Festus
Glencoe
Clayton
Edwardsville
Litchfield
Grafton

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

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