Is Southwest the cheapest airline to fly with from Washington, D.C. Reagan-National Airport to St. Louis?

Yes, based on our data, Southwest is the cheapest airline to fly the route with an average price of $313 return. The next cheapest options are Delta and American Airlines, with return flights costing on average $328 and $330 respectively.

Does Southwest fly direct to St. Louis from Washington, D.C. Reagan-National Airport?

Yes, Southwest does offer direct flights for the route, with around 22 flights per week.

What’s the cheapest day of the week to fly from Washington, D.C. Reagan-National Airport to St. Louis with Southwest?

On average, the cheapest day of the week to fly from Washington, D.C. Reagan-National Airport to St. Louis with Southwest is Saturday, when prices are around $86. The most expensive day is generally Friday, where the average price is around $110.

What’s the cheapest month to fly from Washington, D.C. Reagan-National Airport to St. Louis with Southwest?

The cheapest month for Southwest flights to St. Louis from Washington, D.C. Reagan-National Airport is generally August, where plane tickets cost $117 on average. If possible, try to avoid the most expensive months of September and October, where tickets cost $266 and $320 respectively.

$110 Cheap Southwest Flights from Washington, D.C. Reagan-National Airport to St. Louis

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Flight Deals

Cheap Southwest Flight Deals from Washington, D.C. Reagan-National Airport to St. Louis

Here are some of the best deals found on KAYAK recently from Southwest for round-trip flights from Washington, D.C. Reagan-National Airport to St. Louis that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.

Discover the best prices for you by selecting your travel dates on KAYAK.

Round-trip

One-way

Last minute

Direct

Recent round-trip Southwest flight deals from Washington, D.C. Reagan-National Airport to St. Louis

Fri, Oct 31 - Sun, Nov 2

6:00 am - 10:10 amDCA-STL

5h 10m1 stop

5:45 pm - 11:40 pmSTL-DCA

4h 55m1 stop

$234Southwest

Find Deal

Thu, Dec 4 - Wed, Dec 17

6:10 am - 1:00 pmDCA-STL

7h 50m1 stop

7:00 pm - 9:55 pmSTL-DCA

1h 55mnonstop

$241Southwest

Find Deal

Thu, Dec 4 - Wed, Dec 17

6:10 am - 1:00 pmDCA-STL

7h 50m1 stop

10:35 am - 6:20 pmSTL-DCA

6h 45m2 stops

$256Southwest

Find Deal

Fri, Oct 31 - Sun, Nov 2

3:30 pm - 4:50 pmDCA-STL

2h 20mnonstop

6:50 pm - 9:45 pmSTL-DCA

1h 55mnonstop

$283Southwest

Find Deal

Wed, Nov 5 - Wed, Nov 12

6:55 pm - 10:20 pmDCA-STL

4h 25m1 stop

11:15 am - 8:45 pmSTL-DCA

8h 30m2 stops

$288Southwest

Find Deal

Fri, Dec 12 - Sun, Dec 14

7:30 pm - 11:10 pmDCA-STL

4h 40m1 stop

6:40 am - 12:00 pmSTL-DCA

4h 20m1 stop

$289Southwest

Find Deal

Fri, Nov 14 - Tue, Nov 18

7:30 pm - 11:10 pmDCA-STL

4h 40m1 stop

11:15 am - 8:45 pmSTL-DCA

8h 30m2 stops

$291Southwest

Find Deal

Wed, Nov 5 - Wed, Nov 12

11:15 am - 5:20 pmDCA-STL

7h 05m2 stops

5:45 am - 3:05 pmSTL-DCA

8h 20m2 stops

$293Southwest

Find Deal

Fri, Dec 5 - Mon, Dec 15

6:10 am - 1:00 pmDCA-STL

7h 50m1 stop

5:45 am - 3:05 pmSTL-DCA

8h 20m2 stops

$294Southwest

Find Deal

Thu, Dec 4 - Wed, Dec 17

11:15 am - 5:20 pmDCA-STL

7h 05m2 stops

5:45 am - 3:05 pmSTL-DCA

8h 20m2 stops

$296Southwest

Find Deal

Useful Info

Low season	January
High season	November
Cheapest flight	$110
Average price round-trip	$293

Best time to beat the crowds with an average 6% drop in price.

Most popular time to fly with an average 16% increase in price.

Flight from Reagan Washington National Airport to St. Louis

(price for this month)

When to Book Flights with Southwest from Washington, D.C. Reagan-National Airport to St. Louis

Average price per month

Flight prices as travel date approaches

Is Southwest the cheapest airline to fly with from Washington, D.C. Reagan-National Airport to St. Louis?
Yes, based on our data, Southwest is the cheapest airline to fly the route with an average price of $313 return. The next cheapest options are Delta and American Airlines, with return flights costing on average $328 and $330 respectively.
What is the cheapest Southwest flight from Washington, D.C. Reagan-National Airport to St. Louis?
In the last 3 days, the lowest price for a flight with Southwest from Washington, D.C. Reagan-National Airport to St. Louis was $199 for a return flight and $81 for a one-way flight.
Does Southwest fly direct to St. Louis from Washington, D.C. Reagan-National Airport?
Yes, Southwest does offer direct flights for the route, with around 22 flights per week.
What’s the cheapest day of the week to fly from Washington, D.C. Reagan-National Airport to St. Louis with Southwest?
On average, the cheapest day of the week to fly from Washington, D.C. Reagan-National Airport to St. Louis with Southwest is Saturday, when prices are around $86. The most expensive day is generally Friday, where the average price is around $110.
What’s the cheapest month to fly from Washington, D.C. Reagan-National Airport to St. Louis with Southwest?
The cheapest month for Southwest flights to St. Louis from Washington, D.C. Reagan-National Airport is generally August, where plane tickets cost $117 on average. If possible, try to avoid the most expensive months of September and October, where tickets cost $266 and $320 respectively.

8.0

Very good4,235 verified ratings

8.6Crew

8.1Boarding

7.0Food

7.5Entertainment

8.0Comfort

Pros +

Cons -

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10.0 Wonderful

Aleksandar, Oct 2025

OAK-SAN

On time, and it was not full flight

4.0 Mediocre

Annette, Oct 2025

LGA-MCI

Flight was delayed due to plane not passing inspection And one of the crew had to time out and we had to wait for another one A 3 hour delay

10.0 Wonderful

Gerald, Oct 2025

SJC-PDX

Boarding quick & efficient. Crew was friendly. Arrived early

6.0 Okay

Hung, Oct 2025

PHX-ABQ

mandatory demand customer to check their carry on because not enough people check bags.

8.0 Very good

Annette, Oct 2025

MCI-LGA

Good non stop is always good

10.0 Wonderful

Gabriel, Sep 2025

DEN-SMF

Connecting flight is on time and boarding was a breeze!

10.0 Wonderful

Gabriel, Sep 2025

LGA-DEN

Easy boarding process. No delays!

10.0 Wonderful

Melissa, Sep 2025

MDW-DTW

Excellent

10.0 Wonderful

Melissa, Sep 2025

MSY-MDW

Excellent. Would encourage Southwest to keep current boarding procedures with free style seating. Makes for a fantastic experience

10.0 Wonderful

Robert, Sep 2025

RNO-LAS

As always, the entire Southwest experience was perfect. Purchasing the tickets on the Southwest web site was effortless, departure and arrival gates were spotless and comfortable, plane was clean and comfortable, crew was excellent and flight was on time. Wheelchair service in Las Vegas at departure was somewhat chaotic and disjointed, but I am not sure if that was Southwest problem, airport problem or combination.

Everything you need to know for your flight from Washington, D.C. Reagan-National Airport to St. Louis

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Cabin class types available on flights to St. Louis

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DCA - STL

$110 Find Cheap Southwest Flights from Washington, D.C. Reagan-National Airport to St. Louis

Search hundreds of travel sites at once for deals on Southwest flights from Washington, D.C. Reagan-National Airport to St. Louis

Cheap Southwest Flight Deals from Washington, D.C. Reagan-National Airport to St. Louis

Recent round-trip Southwest flight deals from Washington, D.C. Reagan-National Airport to St. Louis

Recent one-way Southwest flight deals from Washington, D.C. Reagan-National Airport to St. Louis

Recent last minute Southwest flight deals from Washington, D.C. Reagan-National Airport to St. Louis

Recent direct Southwest flight deals from Washington, D.C. Reagan-National Airport to St. Louis

Good to know

When to Book Flights with Southwest from Washington, D.C. Reagan-National Airport to St. Louis

FAQs for flying to St. Louis with Southwest

Is Southwest the cheapest airline to fly with from Washington, D.C. Reagan-National Airport to St. Louis?

What is the cheapest Southwest flight from Washington, D.C. Reagan-National Airport to St. Louis?

Does Southwest fly direct to St. Louis from Washington, D.C. Reagan-National Airport?

What’s the cheapest day of the week to fly from Washington, D.C. Reagan-National Airport to St. Louis with Southwest?

What’s the cheapest month to fly from Washington, D.C. Reagan-National Airport to St. Louis with Southwest?

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Everything you need to know for your flight from Washington, D.C. Reagan-National Airport to St. Louis

Cabin class types available on flights to St. Louis

Cabin classes available on flights to Washington, D.C. Reagan-National Airport. Prices are the lowest found on KAYAK over the last 7 days. Price and availability is not guaranteed.

Complete your trip to St. Louis with a hotel stay or car rental

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The most popular flights on KAYAK according to clicks in the last 2 weeks. Prices are the lowest found on KAYAK over the last 7 days. Price and availability is not guaranteed.

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Top Southwest flights

The most popular destinations for flights with Southwest according to clicks from KAYAK users. Prices are the lowest found on KAYAK over the last 7 days. Price and availability is not guaranteed.