$126+ Cheap flights from Reagan-National (DCA) to St. Louis (STL)
This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 12/12. Fares are subject to change and may not be available on all flights or dates of travel.
DCA — STL
Oct 15 — Oct 221
Round-trip
1 adult, Economy
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Find cheap flights from Reagan-National to St. Louis with Cheapflights
1. Tell us where you want to go
Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”2. Select your favorite providers
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Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.Cheapflights Tip: The best prices from Washington, D.C. Reagan-National to Lambert-St Louis are usually found in January or September, booked 48 days in advance, depart on a Wednesday or Thursday and return on a Saturday
Cheap flight deals from Reagan-National to St. Louis
Cheapest
Best
Last-minute
One-way
Cheapest flights from Reagan-National to St. LouisExplore the most affordable flight options available from Reagan-National to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 15, 2026.
Explore the most affordable flight options available from Reagan-National to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 15, 2026.
This Southwest deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/16:05 am -
1 stop5h 55m
Mon 10/56:10 pm -
1 stop4h 25m
Deal found 9/10![Southwest logo]()
$237
This Southwest deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/218:00 am -
Nonstop2h 25m
Sat 10/246:05 am -
1 stop6h 55m
Deal found 9/14![Southwest logo]()
$241
This Southwest deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/1212:00 pm -
2 stops8h 10m
Mon 11/1610:20 am -
1 stop7h 30m
Deal found 9/10![Southwest logo]()
$242
This Southwest deal was found by Cheapflights users on 9/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/2112:20 pm -
Nonstop2h 25m
Mon 10/267:50 pm -
Nonstop2h 05m
Deal found 9/13![Southwest logo]()
$243
This American Airlines deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/216:55 pm -
Nonstop2h 37m
Wed 10/289:17 am -
1 stop4h 56m
Deal found 9/10![American Airlines logo]()
$246
This Expedia deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/267:00 am -
1 stop13h 15m
Fri 10/307:59 pm -
1 stop24h 51m
Deal found 9/10![Frontier logo]()
$247
This Delta deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/216:59 am -
1 stop4h 52m
Sat 10/245:38 pm -
1 stop5h 10m
Deal found 9/14![Delta logo]()
$251
This Southwest deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/176:05 am -
1 stop11h 00m
Tue 10/2010:20 am -
1 stop3h 10m
Deal found 9/14![Southwest logo]()
$252
This Southwest deal was found by Cheapflights users on 9/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/158:00 am -
Nonstop2h 25m
Mon 10/191:15 pm -
Nonstop2h 00m
Deal found 9/11![Southwest logo]()
$255
This American Airlines deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/17:59 pm -
Nonstop2h 25m
Fri 10/25:00 am -
1 stop4h 52m
Deal found 9/10![American Airlines logo]()
$256
This American Airlines deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/307:59 pm -
Nonstop2h 38m
Tue 12/15:00 am -
1 stop4h 58m
Deal found 9/14![American Airlines logo]()
$257
Best flights from Reagan-National to St. LouisDiscover carefully curated flight deals from Reagan-National to St. Louis that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated September 15, 2026.
Discover carefully curated flight deals from Reagan-National to St. Louis that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated September 15, 2026.
This Delta deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 2/45:15 pm -
1 stop4h 22m
Mon 2/81:01 pm -
1 stop7h 04m
Deal found 9/10![Delta logo]()
$237
This Southwest deal was found by Cheapflights users on 9/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/146:00 am -
1 stop8h 30m
Wed 10/2110:20 am -
1 stop3h 10m
Deal found 9/12![Southwest logo]()
$270
This United Airlines deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/310:30 am -
1 stop4h 46m
Mon 10/511:35 am -
1 stop5h 58m
Deal found 9/14![United Airlines logo]()
$457
This Southwest deal was found by Cheapflights users on 9/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/212:00 pm -
2 stops8h 10m
Wed 11/45:30 am -
1 stop7h 30m
Deal found 9/12![Southwest logo]()
$280
This Southwest deal was found by Cheapflights users on 9/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/156:05 am -
1 stop5h 55m
Sat 10/176:05 am -
2 stops6h 50m
Deal found 9/13![Southwest logo]()
$299
This Delta deal was found by Cheapflights users on 9/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/156:10 am -
1 stop6h 37m
Mon 10/195:35 pm -
1 stop5h 12m
Deal found 9/11![Delta logo]()
$337
This Southwest deal was found by Cheapflights users on 9/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/52:40 pm -
Nonstop2h 25m
Fri 11/68:20 am -
Nonstop1h 55m
Deal found 9/11![Southwest logo]()
$299
This Southwest deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/156:00 pm -
1 stop6h 20m
Sun 10/188:20 am -
Nonstop2h 00m
Deal found 9/10![Southwest logo]()
$312
This Southwest deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/221:05 pm -
1 stop6h 55m
Sun 10/2510:15 am -
1 stop7h 05m
Deal found 9/10![Southwest logo]()
$322
This Southwest deal was found by Cheapflights users on 9/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 12/196:55 pm -
Nonstop2h 30m
Sun 12/278:10 am -
Nonstop1h 55m
Deal found 9/13![Southwest logo]()
$458
Last-minute flights from Reagan-National to St. LouisDiscover last-minute flight deals from Reagan-National to St. Louis. Data last updated September 15, 2026 and is based on user searches.
Discover last-minute flight deals from Reagan-National to St. Louis. Data last updated September 15, 2026 and is based on user searches.
This CheapOair deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/307:00 am -
1 stop13h 17m
Fri 10/28:10 pm -
1 stop15h 01m
Deal found 9/10![Frontier logo]()
$259
This Southwest deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/16:05 am -
1 stop5h 55m
Mon 10/56:10 pm -
1 stop4h 25m
Deal found 9/10![Southwest logo]()
$237
This American Airlines deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/17:59 pm -
Nonstop2h 25m
Fri 10/25:00 am -
1 stop4h 52m
Deal found 9/10![American Airlines logo]()
$256
This Southwest deal was found by Cheapflights users on 9/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/143:05 pm -
Nonstop2h 25m
Wed 10/2110:20 am -
1 stop3h 10m
Deal found 9/12![Southwest logo]()
$261
This Southwest deal was found by Cheapflights users on 9/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/158:00 am -
Nonstop2h 25m
Mon 10/191:15 pm -
Nonstop2h 00m
Deal found 9/11![Southwest logo]()
$255
This Southwest deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/176:05 am -
1 stop11h 00m
Tue 10/2010:20 am -
1 stop3h 10m
Deal found 9/14![Southwest logo]()
$252
This Southwest deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/218:00 am -
Nonstop2h 25m
Sat 10/246:05 am -
1 stop6h 55m
Deal found 9/14![Southwest logo]()
$241
This Southwest deal was found by Cheapflights users on 9/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/2112:20 pm -
Nonstop2h 25m
Mon 10/267:50 pm -
Nonstop2h 05m
Deal found 9/13![Southwest logo]()
$243
This American Airlines deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/216:55 pm -
Nonstop2h 37m
Wed 10/289:17 am -
1 stop4h 56m
Deal found 9/10![American Airlines logo]()
$246
This Delta deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/216:59 am -
1 stop4h 52m
Sat 10/245:38 pm -
1 stop5h 10m
Deal found 9/14![Delta logo]()
$251
This Expedia deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/267:00 am -
1 stop13h 15m
Fri 10/307:59 pm -
1 stop24h 51m
Deal found 9/10![Frontier logo]()
$247
One-way flights from Reagan-National to St. LouisSearch for one-way flight options from Reagan-National to St. Louis. Find affordable one-way fares based on user searches. Data last updated September 15, 2026.
Search for one-way flight options from Reagan-National to St. Louis. Find affordable one-way fares based on user searches. Data last updated September 15, 2026.
This Delta deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 12/122:00 pm -
1 stop7h 09m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/14![Delta logo]()
$126
This Southwest deal was found by Cheapflights users on 9/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/238:25 am -
Nonstop2h 30m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/13![Southwest logo]()
$128
This Delta deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/610:10 am -
1 stop7h 18m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/10![Delta logo]()
$129
This Southwest deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 12/128:00 am -
2 stops9h 50m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/14![Southwest logo]()
$131
This American Airlines deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/56:55 pm -
Nonstop2h 37m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/14![American Airlines logo]()
$132
This Booking.com deal was found by Cheapflights users on 9/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/106:00 pm -
1 stop22h 23m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/11![Frontier logo]()
$135
This Southwest deal was found by Cheapflights users on 9/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/147:00 am -
2 stops14h 10m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/15![Southwest logo]()
$137
This Delta deal was found by Cheapflights users on 9/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/126:05 am -
1 stop6h 43m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/15![Delta logo]()
$138
This Frontier deal was found by Cheapflights users on 9/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/147:00 am -
1 stop9h 24m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/12![Frontier logo]()
$139
This Super.com deal was found by Cheapflights users on 9/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/61:00 pm -
1 stop7h 14m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/13![Frontier logo]()
$140
This Frontier deal was found by Cheapflights users on 9/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/131:00 pm -
1 stop7h 14m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/13![Frontier logo]()
$141
This Southwest deal was found by Cheapflights users on 9/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/1212:00 pm -
2 stops8h 10m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/13![Southwest logo]()
$143
Find flight deals from Reagan-National to St. Louis
Discover tips and strategies to find the most affordable flight options for your journey from Reagan-National (DCA) to St. Louis (STL). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated September 15, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $237 (Southwest) |
One-way from | $126 (Delta) |
Popular in | August |
Cheapest in | January |
Average price | $357 |
Good round-trip deal | $296 or less |
Good one-way deal | $208 or less |
Cheapflights Fare Finder
Customize your flight search to find flights from Reagan-National to St. Louis that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 7,457,451 searches. Data last updated September 15, 2026.
Use the filters below to find and compare flights from Washington, D.C. Reagan-National Airport to St. Louis that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
Washington, D.C.St. Louis
DCA Washington, D.C. Reagan-National - STL Lambert-St Louis
DCASTL
Washington, D.C. Reagan-National
Tue 12/15
1:15 pm-8:26 pm
1 stop8h 11m
Lambert-St Louis
Wed 12/31
12:00 am-1:00 am
Nonstop0h 00m
$126
Washington, D.C.St. Louis
DCA Washington, D.C. Reagan-National - STL Lambert-St Louis
DCASTL
Washington, D.C. Reagan-National
Sat 12/12
2:00 pm-8:09 pm
1 stop7h 09m
Lambert-St Louis
Wed 12/31
12:00 am-1:00 am
Nonstop0h 00m
$126
Washington, D.C.St. Louis
DCA Washington, D.C. Reagan-National - STL Lambert-St Louis
DCASTL
Washington, D.C. Reagan-National
Mon 12/14
11:00 am-5:10 pm
1 stop7h 10m
Lambert-St Louis
Wed 12/31
12:00 am-1:00 am
Nonstop0h 00m
$138
Washington, D.C.St. Louis
DCA Washington, D.C. Reagan-National - STL Lambert-St Louis
DCASTL
Washington, D.C. Reagan-National
Thu 12/17
6:10 am-9:23 am
1 stop4h 13m
Lambert-St Louis
Wed 12/31
12:00 am-1:00 am
Nonstop0h 00m
$138
Washington, D.C.St. Louis
DCA Washington, D.C. Reagan-National - STL Lambert-St Louis
DCASTL
Washington, D.C. Reagan-National
Tue 11/10
6:00 am-11:15 am
1 stop6h 15m
Lambert-St Louis
Wed 12/31
12:00 am-1:00 am
Nonstop0h 00m
$138
Washington, D.C.St. Louis
DCA Washington, D.C. Reagan-National - STL Lambert-St Louis
DCASTL
Washington, D.C. Reagan-National
Tue 10/13
5:35 pm-8:51 pm
1 stop4h 16m
Lambert-St Louis
Wed 12/31
12:00 am-1:00 am
Nonstop0h 00m
$138
Washington, D.C.St. Louis
DCA Washington, D.C. Reagan-National - STL Lambert-St Louis
DCASTL
Washington, D.C. Reagan-National
Sat 11/14
12:26 pm-4:23 pm
1 stop4h 57m
Lambert-St Louis
Wed 12/31
12:00 am-1:00 am
Nonstop0h 00m
$138
Washington, D.C.St. Louis
DCA Washington, D.C. Reagan-National - STL Lambert-St Louis
DCASTL
Washington, D.C. Reagan-National
Thu 11/12
12:00 pm-7:10 pm
2 stops8h 10m
Lambert-St Louis
Wed 12/31
12:00 am-1:00 am
Nonstop0h 00m
$143
Quickest round-trip
Washington, D.C.St. Louis
DCA Washington, D.C. Reagan-National - STL Lambert-St Louis
DCASTL
Washington, D.C. Reagan-National
Sat 10/3
6:40 pm-8:05 pm
Nonstop2h 25m
Lambert-St Louis
Wed 12/31
12:00 am-1:00 am
Nonstop0h 00m
$147
Washington, D.C.St. Louis
DCA Washington, D.C. Reagan-National - STL Lambert-St Louis
DCASTL
Washington, D.C. Reagan-National
Thu 12/10
9:40 am-1:30 pm
1 stop4h 50m
Lambert-St Louis
Wed 12/31
12:00 am-1:00 am
Nonstop0h 00m
$148
Showing 1-10 of 21 resultsSorted by cheapest first
Compare providers for flights from Reagan-National to St. Louis
Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Reagan-National to St. Louis in September.
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars |
- Most accurate provider: When it comes to deals on Washington, D.C. Reagan-National Airport-St. Louis flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Washington, D.C. Reagan-National Airport-St. Louis flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Washington, D.C. Reagan-National Airport-St. Louis flight searches over the past month and is updated monthly.
- Most trusted provider: When it comes to deals on Washington, D.C. Reagan-National Airport-St. Louis flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Washington, D.C. Reagan-National Airport-St. Louis flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.
Best time to book a flight from Reagan-National to St. Louis
Have a flexible travel schedule? Discover the best time to fly to St. Louis from Reagan-National with our price prediction graph.
DCA-STL
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.
Cheapflights Insights
Everything you need to know about your flight from Washington, D.C. Reagan-National Airport to St. Louis
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How far ahead should I book a flight from Washington, D.C. Reagan-National Airport to St. Louis?
The best time to book flights from Washington, D.C. Reagan-National Airport to St. Louis is 47 days before your desired departure date. The cost of your flight will likely increase significantly if you book two weeks in advance of your flight.
What is the cheapest month to book a flight from Washington, D.C. Reagan-National Airport to St. Louis?
Currently, January is the cheapest month in which you can book a flight from Washington, D.C. Reagan-National Airport to St. Louis (average of $309). Flying from Washington, D.C. Reagan-National Airport to St. Louis in August is currently the most expensive (average of $482). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.
What is the cheapest time of day to fly from DCA to STL?
Find hourly flight availability from Reagan-National to St. Louis. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated September 15, 2026.
It’s optimal to fly from Washington, D.C. Reagan-National Airport to St. Louis at noon. By choosing this option you can save up to 8% on the cost of your flight, compared to a flight in the evening.
What is the cheapest day to fly from Washington, D.C. Reagan-National Airport to St. Louis?
Use this chart to determine the cheapest time to fly round-trip from Reagan-National to St. Louis. Price data was last updated on September 12, 2026.
Travelers seeking maximum savings on their Washington, D.C. Reagan-National Airport to St. Louis flight should consider departing on Tuesday evenings when fares are most often at their lowest. Sunday at noon flights should be avoided if possible as fares are typically the most expensive at this time.
The best insider tips for Washington, D.C. Reagan-National Airport to St. Louis flights
AI-powered summary based on content written by travel experts. AI can make mistakes.
Cheapflights partnered with top experts to bring you the best recommendations for your Washington, D.C. Reagan-National Airport to St. Louis trip
Our travel experts
Reviews of airlines servicing St. Louis
Get insights into the airlines that provide service to St. Louis. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to St. Louis. Reviews last updated September 15, 2026.
Peruse reviews from past customers who have flown with Southwest and American Airlines from Washington, D.C. Reagan-National Airport to St. Louis to help guide your decision. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Food
7.0
Boarding
8.1
Entertainment
7.5
Comfort
8.0
Crew
8.6
Overall
8.0
Reviews
1 / 20
10.0
ExcellentCourtney,Sep 2026
DEN - STL
Food
7.0
Boarding
8.1
Entertainment
7.5
Comfort
8.0
Crew
8.6
Overall
8.0
Reviews
1 / 20
10.0
ExcellentCourtney,Sep 2026
DEN - STL
Food
7.0
Boarding
8.1
Entertainment
7.5
Comfort
8.0
Crew
8.6
Overall
8.0
Reviews
1 / 20
10.0
ExcellentCourtney,Sep 2026
DEN - STL
Related info for your journey
Find useful and relevant information for your journey from Reagan-National to St. Louis. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
Traveling to a place near St. Louis?
Book flights to St. Louis if you plan to visit one of these locationsFairview Heights
O'Fallon
Fenton
Swansea
Eureka
Maryland Heights
Collinsville
Wentzville
Edwardsville
Glencoe
Chesterfield
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Reagan-National and St. Louis flights
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Top 2 airlines flying from Reagan-National to St. Louis
Discover the top 2 airlines that operate flights from Reagan-National to St. Louis. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 7,457,451 searches. Data last updated September 15, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$204 | Average$382 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$235 | Average$408 | FlexibilityNo cancel fee | On-time63% |