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Cheap flights from Washington, D.C. Reagan-National Airport to St. Louis from $78

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. Reagan-National Airport to St. Louis departing on 10/15. 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. Reagan-National Airport to St. Louis

Cheap round-trip flights

American Airlines Logo
7:51 pm - 9:02 pmDCA-STL
2h 11mnonstop
American Airlines Logo
5:52 pm - 8:53 pmSTL-DCA
2h 01mnonstop
$157American Airlines
Find Deal
Thu, Aug 7 - Mon, Aug 11
Southwest Logo
12:00 pm - 1:10 pmDCA-STL
2h 10mnonstop
Southwest Logo
1:35 pm - 6:55 pmSTL-DCA
4h 20m1 stop
$167Southwest
Find Deal
Mon, Aug 25 - Tue, Aug 26
Southwest Logo
10:55 am - 5:50 pmDCA-STL
7h 55m2 stops
Southwest Logo
7:20 pm - 10:25 pmSTL-DCA
2h 05mnonstop
$172Southwest
Find Deal
Wed, Sep 10 - Wed, Sep 10
American Airlines Logo
2:56 pm - 4:15 pmDCA-STL
2h 19mnonstop
American Airlines Logo
6:00 pm - 9:00 pmSTL-DCA
2h 00mnonstop
$178American Airlines
Find Deal
Sat, Sep 6 - Mon, Sep 8
Delta Logo
12:20 pm - 4:06 pmDCA-STL
4h 46m1 stop
Delta Logo
6:00 am - 12:39 pmSTL-DCA
5h 39m1 stop
$197Delta
Find Deal
Mon, Aug 25 - Tue, Aug 26
United Airlines Logo
12:00 pm - 3:47 pmDCA-STL
4h 47m1 stop
United Airlines Logo
5:00 am - 10:56 amSTL-DCA
4h 56m1 stop
$198United Airlines
Find Deal
Wed, Aug 6 - Sat, Aug 9
Delta Logo
6:00 am - 9:15 amDCA-STL
4h 15m1 stop
Delta Logo
1:30 pm - 6:34 pmSTL-DCA
4h 04m1 stop
$199Delta
Find Deal
Tue, Jul 1 - Tue, Jul 1
United Airlines Logo
8:30 am - 12:27 pmDCA-STL
4h 57m1 stop
United Airlines Logo
5:00 am - 10:56 amSTL-DCA
4h 56m1 stop
$213United Airlines
Find Deal
Wed, Jul 30 - Wed, Aug 6
Frontier Logo
6:00 pm - 9:12 amDCA-STL
16h 12m1 stop
Frontier Logo
7:29 pm - 12:04 pmSTL-DCA
15h 35m1 stop
$270Frontier
Find Deal
Thu, Jul 3 - Mon, Jul 7
Frontier Logo
7:00 am - 9:11 amDCA-STL
27h 11m1 stop
Frontier Logo
7:29 pm - 12:04 pmSTL-DCA
15h 35m1 stop
$272Frontier
Find Deal
Sun, Jul 20 - Wed, Jul 23

Southwest flights from Washington, D.C. Reagan-National Airport to St. Louis

Our best Southwest deals on Washington, D.C. Reagan-National Airport to St. Louis flight tickets
Southwest
Aug 25
DCA12:00 pmWashington, D.C. Reagan-National
2h 10m
STL1:10 pmLambert-St Louis
Aug 26
STL1:35 pmLambert-St Louis
4h 20m
1 stop
DCA6:55 pmWashington, D.C. Reagan-National
Southwest
Sep 10
DCA10:55 amWashington, D.C. Reagan-National
7h 55m
2 stops
STL5:50 pmLambert-St Louis
Sep 10
STL7:20 pmLambert-St Louis
2h 05m
DCA10:25 pmWashington, D.C. Reagan-National
Southwest
Aug 25
DCA6:10 amWashington, D.C. Reagan-National
5h 55m
1 stop
STL11:05 amLambert-St Louis
Aug 26
STL7:45 amLambert-St Louis
7h 30m
1 stop
DCA4:15 pmWashington, D.C. Reagan-National

Delta flights from Washington, D.C. Reagan-National Airport to St. Louis

Our best Delta deals on Washington, D.C. Reagan-National Airport to St. Louis flight tickets
Delta
Aug 25
DCA12:20 pmWashington, D.C. Reagan-National
4h 46m
1 stop
STL4:06 pmLambert-St Louis
Aug 26
STL6:00 amLambert-St Louis
5h 39m
1 stop
DCA12:39 pmWashington, D.C. Reagan-National
Delta
Jul 1
DCA6:00 amWashington, D.C. Reagan-National
4h 15m
1 stop
STL9:15 amLambert-St Louis
Jul 1
STL1:30 pmLambert-St Louis
4h 04m
1 stop
DCA6:34 pmWashington, D.C. Reagan-National
Delta
Sep 6
DCA10:11 amWashington, D.C. Reagan-National
5h 17m
1 stop
STL2:28 pmLambert-St Louis
Sep 8
STL5:11 pmLambert-St Louis
5h 35m
1 stop
DCA11:46 pmWashington, D.C. Reagan-National

See travel insights to St. Louis from

How to get the cheapest flight ticket from Washington, D.C. Reagan-National Airport 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 cheapest month to fly to St. Louis?

In general, February is the cheapest month to fly from Washington, D.C. Reagan-National Airport 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 July is another great option to travel to St. Louis, with average flight prices from Washington, D.C. Reagan-National Airport averaging around $296.

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 $355. 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 $399. 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. Reagan-National Airport at noon is the least expensive time of day to depart. momondo users have found prices as low as $310 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 $384 per ticket.

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

Fly from Washington, D.C. Reagan-National to Lambert-St Louis for the best Washington, D.C. Reagan-National - 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. Reagan-National Airport when booking 12 weeks ahead of your departure date. In general, you can expect to find flights to St. Louis for around $328 when searching 12 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. Reagan-National Airport for as low as $255 on momondo.

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

There are 3 cabin classes available to choose from on Washington, D.C. Reagan-National 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. Reagan-National Airport to St. Louis flight prices changed over time?

As of June 2025, prices for Washington, D.C. Reagan-National Airport to St. Louis flights are approximately 8% cheaper when compared to flights at the same time last year.

When to book flights from Washington, D.C. Reagan-National Airport to St. Louis

Are you open to changing your travel dates? Check out the ideal times to fly from Washington, D.C. Reagan-National Airport 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. Reagan-National Airport to St. Louis (DCA to STL) flight deals and tips

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

Best Price Found

$78

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. Reagan-National Airport in the past 72 hours is $78. The best round-trip flight deal from Washington, D.C. Reagan-National Airport to St. Louis found on momondo in the last 72 hours is $157.
The fastest flight from Washington, D.C. Reagan-National Airport to St. Louis takes 2h 10m
Direct flights go from Washington, D.C. Reagan-National Airport to St. Louis every day.
There is 1 airport near St. Louis: Lambert-St Louis (STL)

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

    Washington, D.C. Reagan-National and Lambert-St Louis are 708.3 mi apart from one another. In terms of flight time, this usually takes a little over 2h 10m.

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

    Prices for flights from Washington, D.C. Reagan-National Airport to Lambert-St Louis Airport were last updated today.

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

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

    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 Washington, D.C. Reagan-National Airport to Lambert-St Louis Airport.

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

    The travel and health documents required for your trip to Lambert-St Louis Airport 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 Lambert-St Louis Airport. 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 Washington, D.C. Reagan-National Airport to St. Louis?

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


Best airlines flying from Washington, D.C. Reagan-National Airport to St. Louis

Compare and see reviews for airlines that fly from Washington, D.C. Reagan-National Airport to St. Louis with momondo
Airline
Rating
Free Cancellation
Price
American AirlinesPriceFrom $195Free CancellationRating
7.2
10,000 reviews
Search American Airlines flights
SouthwestPriceFrom $198Free CancellationRating
8.0
4,287 reviews
Search Southwest flights
United AirlinesPriceFrom $223Free CancellationRating
7.4
8,790 reviews
Search United Airlines flights
DeltaPriceFrom $232Free CancellationRating
8.0
7,946 reviews
Search Delta flights
  • Southwest Flights From Washington, D.C. Reagan-National Airport to St. Louis

    Southwest flies from Washington, D.C. Reagan-National Airport to St. Louis around 27 times per week, with 4,287 momondo users rating the airline 8.0/10. The cheapest Southwest deal from Washington, D.C. Reagan-National Airport to St. Louis in the last 72 hours was $198 (round-trip), much lower than the average airfare cost of $322 for Southwest flights on this route.

  • American Airlines Flights From Washington, D.C. Reagan-National Airport to St. Louis

    American Airlines (7.2/10 from 10,000 reviews) operates around 17 flights from Washington, D.C. Reagan-National Airport to St. Louis in any given week. The average American Airlines airfare for this route is around $332, with deals from around $195 rare but found on momondo. Referenced prices are for round-trip Washington, D.C. Reagan-National Airport 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
Florissant
Fairview Heights
Maryland Heights
Collinsville
Fenton
Farmington
O'Fallon
Alton
St. Peters
Wentzville
Glencoe
Festus
Clayton
Eureka
Edwardsville
Grafton
Shrewsbury

Why use momondo?

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

momondo compares prices from hundreds of airlines and agents so you can find and book the best deal on flights from Washington, D.C. to St. Louis. Millions of users trust and use momondo every year so you are in good hands.

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

Yes. momondo enables you to select and highlight flights to St. Louis from Washington, D.C. with this policy.

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

momondo offers useful filters to help you find the right flight. Choose specific flight times, airports or even what payment method you prefer. We have numerous options to help you book your ideal flight from Washington, D.C. to St. Louis.

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

Price alerts on flights to St. Louis from Washington, D.C. are quick and easy to set up on momondo. Simply perform a search and select the price alert feature. It is as simple as that.


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Tue 6/17
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