Cheap Flight Tickets from Washington (IAD) to St Louis (STL), Starting at $336

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

AA American Airlines • 1 stop • 10h 6m

Aug 15 – Aug 20

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

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Cheapest Direct Flight

$339

WN Southwest Airlines • nonstop • 3h 30m

Aug 15

The cheapest nonstop flight from Washington to St Louis (IAD-STL) is currently $339

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Fastest Flight

3h 30m

The fastest nonstop flight from Washington to St Louis (IAD-STL) takes 3h 30m

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.

Aug 15 - Aug 20, Economy
AA
Washington → St Louis
10h 6m
5:34 PM - 10:40 PM • 1 stop
AA
Washington → St Louis
7h 11m
3:25 PM - 8:56 PM • 1 stop
$336
American Airlines
Aug 15 - Aug 20, Economy
UA
Washington → St Louis
3h 34m
8:25 AM - 9:39 AM • nonstop
UA
Washington → St Louis
8h 52m
9:30 AM - 4:02 PM • 1 stop
$372
United Airlines
Aug 15 - Aug 20, Economy
DL
Washington → St Louis
11h 45m
8:28 AM - 2:33 PM • 1 stop
DL
Washington → St Louis
7h 16m
12:52 PM - 6:28 PM • 1 stop
$420
Delta Airlines
Aug 15 - Aug 20, Economy
DL
Washington → St Louis
9h 4m
12:30 PM - 5:14 PM • 1 stop
DL
Washington → St Louis
10h 5m
7:00 AM - 2:05 PM • 1 stop
$420
Delta Airlines
Aug 15 - Aug 20, Economy
DL
Washington → St Louis
7h 8m
8:28 AM - 11:56 AM • 1 stop
DL
Washington → St Louis
8h 25m
10:33 AM - 4:38 PM • 1 stop
$420
Delta Airlines
Aug 15 - Aug 20, Economy
UA
Washington → St Louis
10h 7m
6:15 AM - 11:22 AM • 1 stop
UA
Washington → St Louis
8h 52m
9:30 AM - 4:02 PM • 1 stop
$427
United 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 6:15 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 420
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 6:40 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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