$90 Cheap Flights from St. Louis (STL) to Washington (DCA)

View $90 flight on Wed, May 28, 2025Opens in a new window

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

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Find available prices by choosing your travel dates.

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

Prices were available within the past 7 days and start at $90 for one-way flights and $179 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Southwest Airlines
Wed, May 28 - Sat, May 31
STL
St. Louis
DCA
Washington
$179 Roundtrip, found 4 hours ago
$179
Roundtrip
found 4 hours ago
Select Southwest Airlines flight, departing Wed, May 28 from St. Louis to Washington, returning Sat, May 31, priced at $179 found 4 hours ago
American Airlines
Wed, May 28 - Thu, May 29
STL
St. Louis
DCA
Washington
$179 Roundtrip, found 2 hours ago
$179
Roundtrip
found 2 hours ago
Select American Airlines flight, departing Wed, May 28 from St. Louis to Washington, returning Thu, May 29, priced at $179 found 2 hours ago
Southwest Airlines
Wed, May 28 - Thu, May 29
STL
St. Louis
DCA
Washington
$188 Roundtrip, found 2 hours ago
$188
Roundtrip
found 2 hours ago
Select Southwest Airlines flight, departing Wed, May 28 from St. Louis to Washington, returning Thu, May 29, priced at $188 found 2 hours ago
Frontier Airlines
Wed, May 28 - Tue, Jun 3
STL
St. Louis
DCA
Washington
$188 Roundtrip, found 1 hour ago
$188
Roundtrip
found 1 hour ago
Select Frontier Airlines flight, departing Wed, May 28 from St. Louis to Washington, returning Tue, Jun 3, priced at $188 found 1 hour ago
Southwest Airlines
Sun, May 25 - Wed, May 28
STL
St. Louis
DCA
Washington
$189 Roundtrip, found 1 day ago
$189
Roundtrip
found 1 day ago
Select Southwest Airlines flight, departing Sun, May 25 from St. Louis to Washington, returning Wed, May 28, priced at $189 found 1 day ago
American Airlines
Wed, May 28 - Thu, May 29
STL
St. Louis
DCA
Washington
$192 Roundtrip, found 2 hours ago
$192
Roundtrip
found 2 hours ago
Select American Airlines flight, departing Wed, May 28 from St. Louis to Washington, returning Thu, May 29, priced at $192 found 2 hours ago
Southwest Airlines
Tue, Jul 1 - Sat, Jul 5
STL
St. Louis
DCA
Washington
$194 Roundtrip, found 11 hours ago
$194
Roundtrip
found 11 hours ago
Select Southwest Airlines flight, departing Tue, Jul 1 from St. Louis to Washington, returning Sat, Jul 5, priced at $194 found 11 hours ago
United
Sat, May 24 - Sun, May 25
STL
St. Louis
DCA
Washington
$194 Roundtrip, found 10 hours ago
$194
Roundtrip
found 10 hours ago
Select United flight, departing Sat, May 24 from St. Louis to Washington, returning Sun, May 25, priced at $194 found 10 hours ago
Southwest Airlines
Sat, May 24 - Sun, May 25
STL
St. Louis
DCA
Washington
$197 Roundtrip, found 10 hours ago
$197
Roundtrip
found 10 hours ago
Select Southwest Airlines flight, departing Sat, May 24 from St. Louis to Washington, returning Sun, May 25, priced at $197 found 10 hours ago
Delta
Wed, May 28 - Thu, May 29
STL
St. Louis
DCA
Washington
$199 Roundtrip, found 2 hours ago
$199
Roundtrip
found 2 hours ago
Select Delta flight, departing Wed, May 28 from St. Louis to Washington, returning Thu, May 29, priced at $199 found 2 hours ago

Frequently asked questions

How much does a flight from Lambert-St. Louis Intl. Airport (STL) to Ronald Reagan Washington National Airport (DCA) cost?
Cheap return flights from Lambert-St. Louis Intl. Airport (STL) to Ronald Reagan Washington National Airport (DCA) start from $179. This information is based on the cheapest price found on Expedia for this return journey departing within the next three months. This airfare is for a Southwest Airlines flight leaving STL on May 17 2025 and touching down at DCA. The price was last updated on April 22 2025 and has not changed since.
What is the cheapest month to fly from STL to DCA?
The cheapest flights from STL to DCA are usually during off-peak season, when demand is lower. To save money, avoid flying during public holidays, school breaks and major local events.
Which airlines fly direct from Lambert-St. Louis Intl. Airport (STL) to Ronald Reagan Washington National Airport (DCA)?
Take a nonstop flight with Southwest Airlines and journey straight from Lambert-St. Louis Intl. Airport (STL) to Ronald Reagan Washington National Airport (DCA).
What is the cheapest airline that flies from STL to DCA?
Currently, the cheapest airline operating one-way flights from STL to DCA is Southwest Airlines. You can take off on this route from $90. This fare is based on the lowest price found on Expedia departing within the next three months. The flight takes off from STL on May 30 2025. Prices were last updated on April 22 2025 and have not changed since.
How many flights per day from Lambert-St. Louis Intl. Airport (STL) to Ronald Reagan Washington National Airport (DCA)?
Daily, an average of 5 nonstop flights take off from Lambert-St. Louis Intl. Airport (STL) to Ronald Reagan Washington National Airport (DCA). Choose the departure time that best fits your schedule.
What are the most popular departure times for flights from Lambert-St. Louis Intl. Airport (STL) to Ronald Reagan Washington National Airport (DCA)?
Flights between STL and DCA are their busiest at 6 AM. If you’re after a more relaxed trip and potentially cheaper fares, look for a time outside the usual busy windows.
What day of the week has the most flights from STL to DCA?
If you travel on a Friday, you’ll get the greatest range of options for flights from Lambert-St. Louis Intl. Airport (STL) to Ronald Reagan Washington National Airport (DCA).
What is the earliest flight from Lambert-St. Louis Intl. Airport (STL) to Ronald Reagan Washington National Airport (DCA)?
Take the earliest flight at around 6:00AM UTC-6, departing from Lambert-St. Louis Intl. Airport (STL). You’ll be in the air for roughly 2h 20m, arriving at Ronald Reagan Washington National Airport (DCA) at approximately 9:20AM UTC-5.
How long does it take to fly from Lambert-St. Louis Intl. Airport (STL) to Ronald Reagan Washington National Airport (DCA)?
It takes roughly 2 hours and 4 minutes to cover the 720 mi from STL to DCA.
What airline has the least delays from STL to DCA?
With 83% of journeys generally arriving as scheduled, American Airlines has the best on-time performance for nonstop flights from Lambert-St. Louis Intl. Airport (STL) to Ronald Reagan Washington National Airport (DCA). To keep track of your flight status and get notifications about any changes, simply head to the Expedia App.
What is the best time to fly from Lambert-St. Louis Intl. Airport (STL) to Ronald Reagan Washington National Airport (DCA)?
To land at Ronald Reagan Washington National Airport (DCA) without delays, opt for a flight that takes off from Lambert-St. Louis Intl. Airport (STL) before 3 PM. The chance of cancellations is 22% higher, on average, for departures after this hour.**Most reliable time of the day and month to travel recommendation is based on January through August 2024 flight status data sourced from OAG’s global flight data platform.
What airports do you fly into for Washington from Lambert-St. Louis Intl. Airport (STL)?
Come in for landing at one of these Washington airports following your direct flight from Lambert-St. Louis Intl. Airport (STL):

  • Ronald Reagan Washington National Airport (DCA)
  • Washington Dulles Intl. Airport (IAD)
  • Baltimore Washington Intl. Thurgood Marshall Airport (BWI)

Is it cheaper to buy a plane ticket from Lambert-St. Louis Intl. Airport (STL) to Ronald Reagan Washington National Airport (DCA) last-minute?
Waiting until just before your trip to book a flight from STL to DCA often results in higher prices. While you may find some last-minute offers, they aren’t always guaranteed. Allow some flexibility in your schedule for the best chance of getting a bargain.
Is it cheaper to book a STL to DCA flight and hotel package?
You’ll generally save money by securing a STL to DCA flight and hotel package compared to booking separately. In fact, you could save hundreds of dollars by bundling with Expedia. And it’s easy to manage everything in one convenient place. Once you’ve selected your ideal flights and accommodations, consider adding extras including car rentals, tours and activities.
Can I cancel or change the date of my flight from Lambert-St. Louis Intl. Airport (STL) to Ronald Reagan Washington National Airport (DCA)?
You can usually reschedule or cancel your STL to DCA flight. However, if it’s been more than 24 hours since booking, additional fees may apply. Refer to your airline’s policies in your itinerary to see what changes are allowed and whether any costs are involved. You’ll also find more information on our Customer Service portal.
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