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Cheap flights from Washington, D.C. Reagan-National Airport 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. Reagan-National Airport to St. Louis departing on 10/29. 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
11:44 am - 1:13 pmDCA-STL
2h 29mnonstop
American Airlines Logo
1:39 pm - 4:47 pmSTL-DCA
2h 08mnonstop
$202American Airlines
Find Deal
Mon, Nov 10 - Sat, Nov 15
American Airlines Logo
4:12 pm - 5:45 pmDCA-STL
2h 33mnonstop
American Airlines Logo
6:16 pm - 9:30 pmSTL-DCA
2h 14mnonstop
$203American Airlines
Find Deal
Tue, Feb 24 - Wed, Feb 25
American Airlines Logo
6:09 am - 12:11 pmDCA-STL
7h 02m1 stop
American Airlines Logo
6:08 pm - 9:10 pmSTL-DCA
2h 02mnonstop
$204American Airlines
Find Deal
Tue, Oct 14 - Fri, Oct 24
Frontier Logo
6:00 pm - 9:07 amDCA-STL
16h 07m1 stop
Frontier Logo
7:45 pm - 12:04 pmSTL-DCA
15h 19m1 stop
$210Frontier
Find Deal
Tue, Nov 11 - Wed, Nov 12
Frontier Logo
6:00 pm - 9:07 amDCA-STL
16h 07m1 stop
Frontier Logo
7:45 pm - 12:04 pmSTL-DCA
15h 19m1 stop
$211Frontier
Find Deal
Thu, Nov 13 - Sun, Nov 16
Southwest Logo
9:00 am - 2:25 pmDCA-STL
6h 25m1 stop
Southwest Logo
8:15 pm - 11:15 pmSTL-DCA
2h 00mnonstop
$213Southwest
Find Deal
Tue, Sep 30 - Fri, Oct 3
Frontier Logo
1:00 pm - 9:06 amDCA-STL
21h 06m1 stop
Frontier Logo
7:55 pm - 4:59 pmSTL-DCA
20h 04m1 stop
$216Frontier
Find Deal
Thu, Sep 25 - Mon, Sep 29
Southwest Logo
12:45 pm - 7:20 pmDCA-STL
7h 35m1 stop
Southwest Logo
6:25 am - 2:30 pmSTL-DCA
7h 05m2 stops
$239Southwest
Find Deal
Thu, Nov 13 - Sat, Nov 15
Southwest Logo
6:30 pm - 7:45 pmDCA-STL
2h 15mnonstop
Southwest Logo
8:25 am - 11:20 amSTL-DCA
1h 55mnonstop
$263Southwest
Find Deal
Sat, Oct 11 - Sat, Oct 18
Southwest Logo
6:10 pm - 7:35 pmDCA-STL
2h 25mnonstop
Southwest Logo
10:35 am - 6:20 pmSTL-DCA
6h 45m2 stops
$272Southwest
Find Deal
Tue, Nov 11 - Wed, Nov 12

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

Our best Frontier deals on Washington, D.C. Reagan-National Airport to St. Louis flight tickets
Frontier
Nov 11
DCA6:00 pmWashington, D.C. Reagan-National
16h 07m
1 stop
STL9:07 amLambert-St Louis
Nov 12
STL7:45 pmLambert-St Louis
15h 19m
1 stop
DCA12:04 pmWashington, D.C. Reagan-National
$210
Find similar
Frontier
Nov 13
DCA6:00 pmWashington, D.C. Reagan-National
16h 07m
1 stop
STL9:07 amLambert-St Louis
Nov 16
STL7:45 pmLambert-St Louis
15h 19m
1 stop
DCA12:04 pmWashington, D.C. Reagan-National
$211
Find similar
Frontier
Sep 25
DCA1:00 pmWashington, D.C. Reagan-National
21h 06m
1 stop
STL9:06 amLambert-St Louis
Sep 29
STL7:55 pmLambert-St Louis
20h 04m
1 stop
DCA4:59 pmWashington, D.C. Reagan-National
$216
Find similar

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

Our best American Airlines deals on Washington, D.C. Reagan-National Airport to St. Louis flight tickets
American Airlines
Nov 10
DCA11:44 amWashington, D.C. Reagan-National
2h 29m
STL1:13 pmLambert-St Louis
Nov 15
STL1:39 pmLambert-St Louis
2h 08m
DCA4:47 pmWashington, D.C. Reagan-National
$202
Find similar
American Airlines
Feb 24
DCA4:12 pmWashington, D.C. Reagan-National
2h 33m
STL5:45 pmLambert-St Louis
Feb 25
STL6:16 pmLambert-St Louis
2h 14m
DCA9:30 pmWashington, D.C. Reagan-National
$203
Find similar
American Airlines
Oct 14
DCA6:09 amWashington, D.C. Reagan-National
7h 02m
1 stop
STL12:11 pmLambert-St Louis
Oct 24
STL6:08 pmLambert-St Louis
2h 02m
DCA9:10 pmWashington, D.C. Reagan-National
$204
Find similar

momondo Fare Finder

 
Customize your flight search to find flights from Washington, D.C. Reagan-National Airport 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 15, 2025.
Use the filters below to find and compare flights from Washington, D.C. Reagan-National Airport to St. Louis that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Washington, D.C.St. Louis

DCA - STL

DCASTL

Washington, D.C. Reagan-National

Mon 11/10

11:44 am-1:13 pm

Nonstop2h 29m

Lambert-St Louis

Sat 11/15

1:39 pm-4:47 pm

Nonstop2h 08m

$202

Washington, D.C.St. Louis

DCA - STL

DCASTL

Washington, D.C. Reagan-National

Tue 2/24

4:12 pm-5:45 pm

Nonstop2h 33m

Lambert-St Louis

Wed 2/25

6:16 pm-9:30 pm

Nonstop2h 14m

$203

Washington, D.C.St. Louis

DCA - STL

DCASTL

Washington, D.C. Reagan-National

Tue 10/14

6:09 am-12:11 pm

1 stop7h 02m

Lambert-St Louis

Fri 10/24

6:08 pm-9:10 pm

Nonstop2h 02m

$204

Washington, D.C.St. Louis

DCA - STL

DCASTL

Washington, D.C. Reagan-National

Tue 11/11

6:00 pm-9:07 am

1 stop16h 07m

Lambert-St Louis

Wed 11/12

7:45 pm-12:04 pm

1 stop15h 19m

$210

Washington, D.C.St. Louis

DCA - STL

DCASTL

Washington, D.C. Reagan-National

Thu 11/13

6:00 pm-9:07 am

1 stop16h 07m

Lambert-St Louis

Sun 11/16

7:45 pm-12:04 pm

1 stop15h 19m

$211

Washington, D.C.St. Louis

DCA - STL

DCASTL

Washington, D.C. Reagan-National

Tue 9/30

9:00 am-2:25 pm

1 stop6h 25m

Lambert-St Louis

Fri 10/3

8:15 pm-11:15 pm

Nonstop2h 00m

$213

Washington, D.C.St. Louis

DCA - STL

DCASTL

Washington, D.C. Reagan-National

Thu 9/25

1:00 pm-9:06 am

1 stop21h 06m

Lambert-St Louis

Mon 9/29

7:55 pm-4:59 pm

1 stop20h 04m

$216

Washington, D.C.St. Louis

DCA - STL

DCASTL

Washington, D.C. Reagan-National

Thu 11/13

12:45 pm-7:20 pm

1 stop7h 35m

Lambert-St Louis

Sat 11/15

6:25 am-2:30 pm

2 stops7h 05m

$239

Washington, D.C.St. Louis

DCA - STL

DCASTL

Washington, D.C. Reagan-National

Sat 10/11

6:30 pm-7:45 pm

Nonstop2h 15m

Lambert-St Louis

Sat 10/18

8:25 am-11:20 am

Nonstop1h 55m

$263

Washington, D.C.St. Louis

DCA - STL

DCASTL

Washington, D.C. Reagan-National

Tue 11/11

6:10 pm-7:35 pm

Nonstop2h 25m

Lambert-St Louis

Wed 11/12

10:35 am-6:20 pm

2 stops6h 45m

$272

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 20 resultsSorted by cheapest first
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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, August 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 $267. The month of February is another great option to travel to St. Louis, with average flight prices from Washington, D.C. Reagan-National Airport averaging around $270.

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 $347. 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 $417. 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 $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. 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 weeks ahead of your departure date. In general, you can expect to find flights to St. Louis for around $318 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. Reagan-National Airport for as low as $227 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 September 2025, prices for Washington, D.C. Reagan-National Airport to St. Louis flights are approximately 12% more expensive 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

$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. Reagan-National Airport in the past 72 hours is $148. 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 $284.
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)
Search flight deals

  • 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 15m.

  • 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 $179Free CancellationRating
7.2
10,000 reviews
Search American Airlines flights
SouthwestPriceFrom $188Free CancellationRating
8.0
4,242 reviews
Search Southwest flights
DeltaPriceFrom $223Free CancellationRating
7.9
7,954 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 26 times per week, with 4,242 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 $188 (round-trip), much lower than the average airfare cost of $311 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 24 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 $331, with deals from around $179 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
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?

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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