For a stress-free departure, reserve parking online at DCA as lots fill up quickly, especially during busy times.

Most accurate provider | eDreams 3 stars |
|---|---|
Most trusted provider | eDreams 3 stars |
Round-trip from | $245 (Southwest) |
One-way from | $64 (Priceline) |
Popular in | December |
Cheapest in | August |
Average price | $340 |
Good round-trip deal | $324 or less |
Good one-way deal | $162 or less |
Fly from
Fly to
Route
Depart
Return
Price
Washington, D.C.St. Louis
DCA - STL
DCASTL
Washington, D.C. Reagan-National
Wed 2/4
8:00 am-9:35 am
Nonstop2h 35m
Lambert-St Louis
Tue 2/10
6:05 am-1:00 pm
1 stop5h 55m
Washington, D.C.St. Louis
DCA - STL
DCASTL
Washington, D.C. Reagan-National
Thu 3/19
6:00 pm-9:49 am
1 stop16h 49m
Lambert-St Louis
Mon 3/23
8:12 pm-1:02 pm
1 stop15h 50m
Washington, D.C.St. Louis
DCA - STL
DCASTL
Washington, D.C. Reagan-National
Wed 2/25
8:00 am-9:35 am
Nonstop2h 35m
Lambert-St Louis
Thu 2/26
9:50 am-6:10 pm
2 stops7h 20m
Washington, D.C.St. Louis
DCA - STL
DCASTL
Washington, D.C. Reagan-National
Tue 2/17
3:55 pm-7:55 pm
1 stop5h 00m
Lambert-St Louis
Thu 2/19
9:50 am-6:10 pm
2 stops7h 20m
Washington, D.C.St. Louis
DCA - STL
DCASTL
Washington, D.C. Reagan-National
Mon 2/9
3:25 pm-5:00 pm
Nonstop2h 35m
Lambert-St Louis
Wed 2/11
10:15 am-6:00 pm
2 stops6h 45m
Washington, D.C.St. Louis
DCA - STL
DCASTL
Washington, D.C. Reagan-National
Thu 2/26
7:51 pm-9:37 pm
Nonstop2h 46m
Lambert-St Louis
Sat 2/28
6:06 am-9:12 am
Nonstop2h 06m
Washington, D.C.St. Louis
DCA - STL
DCASTL
Washington, D.C. Reagan-National
Sat 5/30
2:59 pm-4:22 pm
Nonstop2h 23m
Lambert-St Louis
Tue 6/2
5:56 pm-9:08 pm
Nonstop2h 12m
Washington, D.C.St. Louis
DCA - STL
DCASTL
Washington, D.C. Reagan-National
Thu 2/12
8:00 am-9:35 am
Nonstop2h 35m
Lambert-St Louis
Thu 2/19
3:55 pm-6:55 pm
Nonstop2h 00m
Washington, D.C.St. Louis
DCA - STL
DCASTL
Washington, D.C. Reagan-National
Wed 3/4
2:55 pm-4:30 pm
Nonstop2h 35m
Lambert-St Louis
Sun 3/8
7:55 pm-10:50 pm
Nonstop1h 55m
Washington, D.C.St. Louis
DCA - STL
DCASTL
Washington, D.C. Reagan-National
Thu 2/26
8:00 am-9:35 am
Nonstop2h 35m
Lambert-St Louis
Sat 2/28
7:50 am-12:50 pm
1 stop4h 00m
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy2 stars | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*1 star | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy1 star | Trust Score*3 stars |
The best time to book flights from Washington, D.C. Reagan-National Airport to St. Louis is 57 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.
Currently, September is the cheapest month in which you can book a flight from Washington, D.C. Reagan-National Airport to St. Louis (average of $154). Flying from Washington, D.C. Reagan-National Airport to St. Louis in December is currently the most expensive (average of $282). 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.
It’s optimal to fly from Washington, D.C. Reagan-National Airport to St. Louis in the evening. By choosing this option you can save up to 16% on the cost of your flight, compared to a flight in the afternoon.
Travelers seeking maximum savings on their Washington, D.C. Reagan-National Airport to St. Louis flight should consider departing on Friday 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.
Comfort
Entertainment
Overall
Boarding
Food
Crew
Reviews
Thomas,Dec 2025
SEA - DEN
Comfort
Entertainment
Overall
Boarding
Food
Crew
Reviews
Thomas,Dec 2025
SEA - DEN
Comfort
Entertainment
Overall
Boarding
Food
Crew
Reviews
Thomas,Dec 2025
SEA - DEN
Comfort
Entertainment
Overall
Boarding
Food
Crew
Reviews
Thomas,Dec 2025
SEA - DEN
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$170 | Average$327 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$186 | Average$335 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$223 | Average$323 | FlexibilityNo cancel fee | On-timeN/A |