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 $311 return. The next cheapest options are Delta and American Airlines, with return flights costing on average $328 and $331 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 16 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 Thursday, where the average price is around $114.

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 February and September, where tickets cost $264 and $270 respectively.

$115 Cheap Southwest Flights from Washington, D.C. Reagan-National Airport to St. Louis

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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

Wed, Nov 12 - Wed, Nov 12

9:30 am - 12:35 pmDCA-STL

4h 05m1 stop

7:00 pm - 9:55 pmSTL-DCA

1h 55mnonstop

$239Southwest

Find Deal

Wed, Nov 12 - Wed, Nov 12

8:15 am - 9:35 amDCA-STL

2h 20mnonstop

11:15 am - 8:45 pmSTL-DCA

8h 30m2 stops

$244Southwest

Find Deal

Tue, Nov 18 - Mon, Nov 24

2:45 pm - 4:05 pmDCA-STL

2h 20mnonstop

1:20 pm - 4:20 pmSTL-DCA

2h 00mnonstop

$253Southwest

Find Deal

Thu, Oct 23 - Mon, Oct 27

3:40 pm - 5:00 pmDCA-STL

2h 20mnonstop

8:00 pm - 10:55 pmSTL-DCA

1h 55mnonstop

$259Southwest

Find Deal

Tue, Nov 18 - Mon, Nov 24

2:45 pm - 4:05 pmDCA-STL

2h 20mnonstop

3:45 pm - 10:50 pmSTL-DCA

6h 05m1 stop

$263Southwest

Find Deal

Fri, Oct 31 - Mon, Nov 3

6:40 pm - 7:55 pmDCA-STL

2h 15mnonstop

3:20 pm - 6:15 pmSTL-DCA

1h 55mnonstop

$268Southwest

Find Deal

Thu, Oct 23 - Mon, Oct 27

3:40 pm - 5:00 pmDCA-STL

2h 20mnonstop

5:40 am - 12:25 pmSTL-DCA

5h 45m1 stop

$269Southwest

Find Deal

Thu, Nov 27 - Tue, Dec 2

6:55 am - 2:25 pmDCA-STL

8h 30m2 stops

5:45 am - 3:05 pmSTL-DCA

8h 20m2 stops

$274Southwest

Find Deal

Thu, Dec 18 - Tue, Dec 30

2:55 pm - 4:20 pmDCA-STL

2h 25mnonstop

8:40 am - 11:35 amSTL-DCA

1h 55mnonstop

$276Southwest

Find Deal

Wed, Nov 12 - Fri, Nov 14

2:45 pm - 4:05 pmDCA-STL

2h 20mnonstop

6:50 pm - 9:45 pmSTL-DCA

1h 55mnonstop

$277Southwest

Find Deal

Useful Info

Low season	January
High season	November
Cheapest flight	$115
Average price round-trip	$298

Best time to beat the crowds with an average 7% drop in price.

Most popular time to fly with an average 15% 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 $311 return. The next cheapest options are Delta and American Airlines, with return flights costing on average $328 and $331 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 $209 for a return flight and $82 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 16 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 Thursday, where the average price is around $114.
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 February and September, where tickets cost $264 and $270 respectively.

8.0

Very good4,248 verified ratings

7.5Entertainment

8.6Crew

7.0Food

8.1Boarding

8.0Comfort

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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.

4.0 Mediocre

Ashish, Sep 2025

PHX-OGG

Southwest airlines boarding process is the worst. Period.

8.0 Very good

Verified traveler, Sep 2025

LAS-DTW

Good

10.0 Wonderful

Verified traveler, Sep 2025

CLT-BWI

Always liked SW

10.0 Wonderful

Lynda, Sep 2025

MDW-OKC

Clear communication

10.0 Wonderful

Lynda, Sep 2025

BNA-MDW

On time-smooth flights-clear communication

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

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$115 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

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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.

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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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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.