Cheap Flight Tickets from Washington (IAD) to St Louis (STL), Starting at $165

Good to Know: Cheapest and Fastest IAD - STL Flights

Useful information for finding best airline tickets from Washington Dulles International to Lambert St Louis International on your next trip.

Cheapest Round Trip Flight

$336

F9 Frontier Airlines • 3 stops • 43h 57m

Dec 07 – Dec 17

The cheapest round trip flight from Washington to St Louis (IAD-STL-IAD) is currently $336

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Cheapest One way Flight

$165

DL Delta Airlines • 1 stop • 14h 2m

Dec 21

The cheapest one way flight from Washington to St Louis (IAD-STL) is currently $165

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Cheapest Direct Flight

$305

WN Southwest Airlines • nonstop • 3h 45m

Dec 07

The cheapest nonstop flight from Washington to St Louis (IAD-STL) is currently $305

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Fastest Flight

2m

The fastest nonstop flight from Washington to St Louis (IAD-STL) takes 2m

Top Airlines Flying from Washington to St Louis

Southwest Airlines-WN

Southwest Airlines

Delta Airline, DL

Delta Airlines

United Airlines, UA

United Airlines

American Airlines, AA

American Airlines

Alaska Airlines -AS

Alaska Airlines

Latest Flight Deals from Washington (IAD) to St Louis (STL)

Compare and book low fare round-trip air tickets from Washington to St Louis. Ideal for travelers with confirmed return itineraries.

Dec 07 - Dec 17, Economy
F9
Washington → St Louis
43h 57m
10:35 PM - 11:04 AM • 3 stops
F9
Washington → St Louis
45h 19m
4:46 PM - 3:13 PM • 2 stops
$336
Frontier Airlines
Dec 07 - Dec 17, Economy
WN
Washington → St Louis
5h 35m
4:50 PM - 7:25 PM • nonstop
WN
Washington → St Louis
2h 35m
8:20 AM - 11:15 AM • nonstop
$378
Southwest Airlines
Dec 07 - Dec 17, Economy
UA
Washington → St Louis
11m
10:10 AM - 2:41 PM • 1 stop
UA
Washington → St Louis
10m
8:05 AM - 2:12 PM • 1 stop
$391
United Airlines
Dec 07 - Dec 17, Economy
DL
Washington → St Louis
11h 53m
6:00 AM - 4:24 PM • 1 stop
DL
Washington → St Louis
6h 58m
6:05 PM - 11:23 PM • 1 stop
$395
Delta Airlines
Dec 07 - Dec 17, Economy
UA
Washington → St Louis
7h 29m
1:00 PM - 7:26 PM • 1 stop
UA
Washington → St Louis
3h 30m
1:23 PM - 4:33 PM • nonstop
$711
United Airlines
Dec 07 - Dec 17, Economy
AA
Washington → St Louis
35m
5:04 PM - 9:44 AM • 1 stop
AA
Washington → St Louis
10m
11:09 AM - 5:31 PM • 1 stop
$777
American Airlines

Fly from Washington to St Louis with the Best Airfare Deals on FareLeaders

Looking for a cheap last-minute deal or the best round-trip flight from Washington to St Louis? Find the biggest savings on one-way and round-trip tickets right here.

FAQs on Washington to St Louis Flights

What are the airports in Washington?
IAD,BWI,DCA
What’s the most popular airline flying from IAD to STL?
The most popular airline flying from Washington to St Louis are
Can I fly from IAD to STL non-stop?
Yes, you can fly IAD to STL non-stop on
Which airlines fly nonstop between Washington and St Louis?
The non-stop flights between Washington and St Louis are .
What’s the earliest departure time from IAD to STL Airport?
The earliest flight leaves IAD at 6:00 am and lands in STL - Lambert St Louis International
What are the airports in St Louis?
STL
Can I make changes to my Washington to St Louis flight tickets or cancel them on FareLeaders.com?
No. We are an airfare comparison site. All the tickets are booked by the travel agent offering the flight deal and any changes or cancellations to be made are directly done directly by them or the airlines.
Can I cancel my flight tickets from IAD to STL?
Read the fare rules of the Washington to St Louis air tickets booked. Some airlines allow you to cancel the tickets within a stipulated time period with a cancellation fee.
Which airline alliances offer flights from Washington and St Louis?
operate flights between Washington and St Louis
How long does a flight from Washington to St Louis take?
It takes approximately 2 hour to fly non-stop from IAD to STL, which is 696.18 miles by air.
Which airlines provide the cheapest flights from Washington (IAD) to St Louis (STL) ?
In the past couple of days, the cheapest tickets to STL from IAD were found on DL : USD 482
Do I need a passport to fly between IAD and STL?
No
What’s the latest departure time from IAD to STL ?
The last flight leaves IAD at 10:35 pm

Washington (IAD) to St Louis (STL): Airport Information

Origin Airport Washington Dulles International , Washington, US
Destination Airport Lambert St Louis International , St Louis, US
Distance 696 miles

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