£100 Cheap Flights from Washington (DCA) to St. Louis (STL)

View £100 flight on Sun, 31 Aug 2025Opens in a new window

Popular airlines from Ronald Reagan National Airport (DCA) to Lambert-St. Louis International Airport (STL)

  • Plan, book, fly with confidence

  • trending down icon

    Be in the know

    Get alerts if flight prices drop or rise*
  • bex rewards loyalty icon

    Book smarter

    Save up to 25% on select hotels after you book a flight*
  • payments icon

    Earn twice

    Earn your airline miles on top of our rewards
    Sign in

Cheap Flights from Washington (DCA) to St. Louis (STL)

Prices were available within the past 7 days and start at £100 for one-way flights and £447 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Alaska Airlines
Thu, 11 Sep - Mon, 15 Sep
DCA
Washington
STL
St. Louis
£447 Return, found 6 days ago
£447
Return
found 6 days ago
Select Alaska Airlines flight, departing Thu, 11 Sep from Washington to St. Louis, returning Mon, 15 Sep, priced at £447 found 6 days ago
Alaska Airlines
Fri, 17 Oct - Mon, 20 Oct
DCA
Washington
STL
St. Louis
£506 Return, found 1 day ago
£506
Return
found 1 day ago
Select Alaska Airlines flight, departing Fri, 17 Oct from Washington to St. Louis, returning Mon, 20 Oct, priced at £506 found 1 day ago
Alaska Airlines
Fri, 17 Oct - Mon, 20 Oct
DCA
Washington
STL
St. Louis
£630 Return, found 1 day ago
£630
Return
found 1 day ago
Select Alaska Airlines flight, departing Fri, 17 Oct from Washington to St. Louis, returning Mon, 20 Oct, priced at £630 found 1 day ago
Alaska Airlines
Wed, 13 Aug - Wed, 20 Aug
DCA
Washington
STL
St. Louis
£749 Return, found 2 days ago
£749
Return
found 2 days ago
Select Alaska Airlines flight, departing Wed, 13 Aug from Washington to St. Louis, returning Wed, 20 Aug, priced at £749 found 2 days ago
Alaska Airlines
Wed, 13 Aug - Wed, 20 Aug
DCA
Washington
STL
St. Louis
£785 Return, found 2 days ago
£785
Return
found 2 days ago
Select Alaska Airlines flight, departing Wed, 13 Aug from Washington to St. Louis, returning Wed, 20 Aug, priced at £785 found 2 days ago
Alaska Airlines
Wed, 13 Aug - Wed, 20 Aug
DCA
Washington
STL
St. Louis
£793 Return, found 4 days ago
£793
Return
found 4 days ago
Select Alaska Airlines flight, departing Wed, 13 Aug from Washington to St. Louis, returning Wed, 20 Aug, priced at £793 found 4 days ago
Alaska Airlines
Fri, 17 Oct - Mon, 20 Oct
DCA
Washington
STL
St. Louis
£819 Return, found 1 day ago
£819
Return
found 1 day ago
Select Alaska Airlines flight, departing Fri, 17 Oct from Washington to St. Louis, returning Mon, 20 Oct, priced at £819 found 1 day ago
Alaska Airlines
Wed, 13 Aug - Wed, 20 Aug
DCA
Washington
STL
St. Louis
£829 Return, found 4 days ago
£829
Return
found 4 days ago
Select Alaska Airlines flight, departing Wed, 13 Aug from Washington to St. Louis, returning Wed, 20 Aug, priced at £829 found 4 days ago
Alaska Airlines
Wed, 13 Aug - Wed, 20 Aug
DCA
Washington
STL
St. Louis
£912 Return, found 2 days ago
£912
Return
found 2 days ago
Select Alaska Airlines flight, departing Wed, 13 Aug from Washington to St. Louis, returning Wed, 20 Aug, priced at £912 found 2 days ago
Alaska Airlines
Tue, 5 Aug - Thu, 7 Aug
DCA
Washington
STL
St. Louis
£931 Return, found 6 days ago
£931
Return
found 6 days ago
Select Alaska Airlines flight, departing Tue, 5 Aug from Washington to St. Louis, returning Thu, 7 Aug, priced at £931 found 6 days ago

Find the cheapest month to fly from Washington (DCA) to St. Louis (STL)

August is typically the cheapest month to fly

From £89 - £417 per traveller.

Graph displaying average flight prices per month

Flight from Washington to St. Louis route information
Origin airport
Ronald Reagan Washington National
Destination airport
Lambert-St. Louis Intl.
Airlines serving
Alaska Airlines
Return price
£447
Distance
1147 km
Average flight time
1 hour 14 mins

Compare flights from Washington to St. Louis easily and book with confidence

For travelling on business or for pleasure, Expedia makes it easy to book your flights from Washington to St. Louis. Operating between them 7 flights per day, 20 airlines cover the route. And American Airlines, Southwest Airlines fly direct, getting you to Lambert-St. Louis Intl. in just 2hours. If you have a preferred carrier, use our advanced search tool to find the right flight from Ronald Reagan Washington National to Lambert-St. Louis Intl..  

To make things even better, in the advanced search, you can also choose to fly economy, premium economy, business or first class, select your maximum number of stops, and pick your preferred departure and arrival time. You can also opt for refundable and direct flights. 

Grab a great deal on your flight from Ronald Reagan Washington National (DCA) to Lambert-St. Louis Intl. (STL)

The easiest way to view the best deals on flights from Washington to St. Louis today is to enter your travel dates and hit search. From here, you can sort your results by price to see the cheapest flights first. Right now, return flights from Ronald Reagan Washington National to Lambert-St. Louis Intl. start at just £447 and range up to £931.  

To find an even better deal, try  

  • being flexible on your dates – midweek flights can be cheaper
  • looking for other airports near Washington and St. Louis
  • booking your flight during September, the cheapest month on this route
  • varying your flight times – early morning and late at night are sometimes cheaper 

Why you should book your Washington to St. Louis flight with Expedia!

We cater for all flight types, cabin classes and airlines. So whether you’re booking flights from Ronald Reagan Washington National to Lambert-St. Louis Intl. for a budget break or a business trip with a bit of pleasure thrown in, we make it easy to secure the seat that’s right for you.  

Thanks to our supersized inventory that offers great choice all in one place, you know you’ll get a great deal with Expedia. Especially if you bundle your flight together with your hotel, you will unlock amazing savings. For added peace of mind, you can choose flexible bookings or filter to find refundable options, so you won’t pay a fee to change your flight.  

Frequently asked questions

How much is a flight from Ronald Reagan Washington National Airport (DCA) to STL?
Within the past 7 days on Expedia, for flights departing within the next year, the lowest price advertised for a round-trip journey between Ronald Reagan Washington National Airport (DCA) and Lambert-St. Louis Intl. Airport (STL) was £447. Fares this good don't last forever, so make sure you book yours ASAP. Prices and availability are subject to change. Additional terms apply.
Do I need to pay a cancellation fee if I cancel my flight from DCA to Lambert Field?
Each airline has its own terms and conditions. If you decide to cancel your trip, visit our Customer Service Portal.
How do I find cheap flights from National Airport to Lambert Field that have flexible change policies?
Many airlines offer the option to reschedule your flight without a change fee. All you pay is the difference between the original flight and the new flight. When you're searching for Ronald Reagan Washington National Airport (DCA) to Lambert Field flights, you'll see a "no change fees" filter for you to select.
How far is the flight from National Airport to St. Louis Lambert International Airport?
It's just 1,150 kilometres between Arlington and St. Louis. Chances are you'll spend more time travelling to and from the airport than actually flying!
Which airlines fly direct from DCA to Lambert-St. Louis Intl. Airport (STL)?
Southwest Airlines (WN) is a popular option. It operates 117 flights between Ronald Reagan Washington National Airport (DCA) and St. Louis Lambert International Airport each month. After more options? Check out the fares with American Airlines (AA). This carrier offers 108 flights every month between these destinations.
Are DCA to Lambert Field flight tickets cheaper when they're purchased at the last minute?
It is possible to get amazing last-minute deals from DCA to Lambert Field, but it can also be hit-or-miss. As many airlines release prices up to a year in advance, it's worthwhile keeping an eye on fares early and being ready to pounce when you spot a good bargain. Expedia compares carrier prices and updates flight deals all the time, so you can feel confident knowing you're always getting the latest offers.

Explore a world of travel with Expedia

Washington Airports

Baltimore

Baltimore Washington Intl. Thurgood Marshall to St. Louis
£456.90

Washington

*Available to Expedia members.