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

View $90 flight on Sat, May 24, 2025Opens in a new window

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

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Find available prices by choosing your travel dates.

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

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 - Thu, May 29
DCA
Washington
STL
St. Louis
$179 Roundtrip, found 2 hours ago
$179
Roundtrip
found 2 hours ago
Select Southwest Airlines flight, departing Wed, May 28 from Washington to St. Louis, returning Thu, May 29, priced at $179 found 2 hours ago
American Airlines
Wed, May 28 - Thu, May 29
DCA
Washington
STL
St. Louis
$179 Roundtrip, found 2 hours ago
$179
Roundtrip
found 2 hours ago
Select American Airlines flight, departing Wed, May 28 from Washington to St. Louis, returning Thu, May 29, priced at $179 found 2 hours ago
Southwest Airlines
Wed, May 28 - Thu, May 29
DCA
Washington
STL
St. Louis
$188 Roundtrip, found 2 hours ago
$188
Roundtrip
found 2 hours ago
Select Southwest Airlines flight, departing Wed, May 28 from Washington to St. Louis, returning Thu, May 29, priced at $188 found 2 hours ago
Frontier Airlines
Tue, May 13 - Wed, May 14
DCA
Washington
STL
St. Louis
$188 Roundtrip, just found
$188
Roundtrip
just found
Select Frontier Airlines flight, departing Tue, May 13 from Washington to St. Louis, returning Wed, May 14, priced at $188 just found
Delta
Wed, May 28 - Thu, May 29
DCA
Washington
STL
St. Louis
$189 Roundtrip, found 2 hours ago
$189
Roundtrip
found 2 hours ago
Select Delta flight, departing Wed, May 28 from Washington to St. Louis, returning Thu, May 29, priced at $189 found 2 hours ago
American Airlines
Thu, May 29 - Sat, May 31
DCA
Washington
STL
St. Louis
$192 Roundtrip, found 13 hours ago
$192
Roundtrip
found 13 hours ago
Select American Airlines flight, departing Thu, May 29 from Washington to St. Louis, returning Sat, May 31, priced at $192 found 13 hours ago
Southwest Airlines
Wed, Jul 2 - Sat, Jul 5
DCA
Washington
STL
St. Louis
$197 Roundtrip, found 1 day ago
$197
Roundtrip
found 1 day ago
Select Southwest Airlines flight, departing Wed, Jul 2 from Washington to St. Louis, returning Sat, Jul 5, priced at $197 found 1 day ago
Southwest Airlines
Tue, Jul 1 - Sat, Jul 5
DCA
Washington
STL
St. Louis
$198 Roundtrip, found 16 hours ago
$198
Roundtrip
found 16 hours ago
Select Southwest Airlines flight, departing Tue, Jul 1 from Washington to St. Louis, returning Sat, Jul 5, priced at $198 found 16 hours ago
United
Thu, May 29 - Sat, May 31
DCA
Washington
STL
St. Louis
$199 Roundtrip, found 13 hours ago
$199
Roundtrip
found 13 hours ago
Select United flight, departing Thu, May 29 from Washington to St. Louis, returning Sat, May 31, priced at $199 found 13 hours ago
Delta
Wed, May 28 - Thu, May 29
DCA
Washington
STL
St. Louis
$199 Roundtrip, found 2 hours ago
$199
Roundtrip
found 2 hours ago
Select Delta flight, departing Wed, May 28 from Washington to St. Louis, returning Thu, May 29, priced at $199 found 2 hours ago

Frequently asked questions

How much does a flight from Ronald Reagan Washington National Airport (DCA) to Lambert-St. Louis Intl. Airport (STL) cost?
You’ll find cheap return flights from Ronald Reagan Washington National Airport (DCA) to Lambert-St. Louis Intl. Airport (STL) starting from $179. Grab a seat and set off on your next adventure. 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 DCA on May 14 2025 and touching down at STL. The price was last updated on April 22 2025 and has not changed since.
What is the cheapest month to fly from DCA to STL?
The cheapest flights from DCA to STL 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 Ronald Reagan Washington National Airport (DCA) to Lambert-St. Louis Intl. Airport (STL)?
Jump on a direct flight with Southwest Airlines and head straight from Ronald Reagan Washington National Airport (DCA) to Lambert-St. Louis Intl. Airport (STL).
What is the cheapest airline that flies from DCA to STL?
Right now, the cheapest carrier operating one-way flights from DCA to STL is Southwest Airlines. You can jet 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 DCA on July 5 2025. Prices were last updated on April 22 2025 and have not changed since.
How many flights per day from Ronald Reagan Washington National Airport (DCA) to Lambert-St. Louis Intl. Airport (STL)?
With an average of 5 nonstop flights departing from Ronald Reagan Washington National Airport (DCA) to Lambert-St. Louis Intl. Airport (STL) every day, you’ll be off on your next adventure in no time.
What are the most popular departure times for flights from Ronald Reagan Washington National Airport (DCA) to Lambert-St. Louis Intl. Airport (STL)?
The 8 AM departures from DCA to STL are the busiest. Prices can be higher for these popular slots. If you want to save on your fare, pick a less crowded time to fly.
What day of the week has the most flights from DCA to STL?
Jet off on a Friday if you’re searching for the biggest selection of flights from Ronald Reagan Washington National Airport (DCA) to Lambert-St. Louis Intl. Airport (STL).
What is the earliest flight from Ronald Reagan Washington National Airport (DCA) to Lambert-St. Louis Intl. Airport (STL)?
The first flight of the day out of Ronald Reagan Washington National Airport (DCA) is at around 8:00AM UTC-5. Hop on this flight and you’ll reach Lambert-St. Louis Intl. Airport (STL) at approximately 9:25AM UTC-6. The total flight duration is 2h 25m.
How long does it take to fly from Ronald Reagan Washington National Airport (DCA) to Lambert-St. Louis Intl. Airport (STL)?
The average flight duration from DCA to STL is 2 hours and 36 minutes, covering a total distance of 720 mi.
What airline has the least delays from DCA to STL?
With 82% of journeys generally arriving as scheduled, American Airlines has the best on-time performance for nonstop flights from Ronald Reagan Washington National Airport (DCA) to Lambert-St. Louis Intl. Airport (STL). To monitor your flight status and get notified if anything changes, use the Expedia App.
What is the best time to fly from Ronald Reagan Washington National Airport (DCA) to Lambert-St. Louis Intl. Airport (STL)?
Opt for a flight from Ronald Reagan Washington National Airport (DCA) to Lambert-St. Louis Intl. Airport (STL) that takes off before 3 PM to reduce the likelihood of delays and cancellations. Departures later than this are on average 22% more likely to be canceled.**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 St. Louis from Ronald Reagan Washington National Airport (DCA)?
If you’re boarding a direct flight from Ronald Reagan Washington National Airport (DCA) to St. Louis, Lambert-St. Louis Intl. Airport (STL) is the only airport you can touch down at.
Is it cheaper to buy a plane ticket from Ronald Reagan Washington National Airport (DCA) to Lambert-St. Louis Intl. Airport (STL) last-minute?
Waiting until just before your trip to book a ticket from DCA to STL generally means paying more. Although you may find some last-minute discounts, they’re not always guaranteed. Keep your travel plans flexible to boost your chances of snagging a bargain.
Is it cheaper to book a DCA to STL flight and hotel package?
You’ll generally save money by booking a DCA to STL flight and hotel package compared to booking separately. In fact, travelers could save hundreds of dollars by bundling with Expedia. And it’s simple to manage it all in one place. After choosing your preferred accommodations and flights, consider other add-ons like car rentals, tours and activities.
Can I cancel or change the date of my flight from Ronald Reagan Washington National Airport (DCA) to Lambert-St. Louis Intl. Airport (STL)?
Typically, you can cancel or modify your DCA to STL flight. However, there may be additional fees, especially if your booking was made more than 24 hours ago. Check your itinerary for the airline’s fees and guidelines on flight changes, or if you’d like more information, go to our Customer Service portal.
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