$112 Cheap United flights from Washington to St. Louis (IAD to STL)

Find The Best Day To Fly from Washington to St. Louis

Amazing United IAD to STL Flight Deals

The cheapest flights to Lambert-St. Louis Intl. found within the past 7 days were $216 round trip and $112 one way. Prices and availability subject to change. Additional terms may apply.

Wed, Aug 27 - Sat, Aug 30
IAD
Washington
STL
St. Louis
$216 Roundtrip, found 4 days ago
$216
Roundtrip
found 4 days ago
Select United flight, departing Wed, Aug 27 from Washington to St. Louis, returning Sat, Aug 30, priced at $216 found 4 days ago
Wed, Aug 27 - Sat, Aug 30
IAD
Washington
STL
St. Louis
$231 Roundtrip, found 4 days ago
$231
Roundtrip
found 4 days ago
Select United flight, departing Wed, Aug 27 from Washington to St. Louis, returning Sat, Aug 30, priced at $231 found 4 days ago
Wed, Aug 27 - Fri, Aug 29
IAD
Washington
STL
St. Louis
$232 Roundtrip, found 4 days ago
$232
Roundtrip
found 4 days ago
Select United flight, departing Wed, Aug 27 from Washington to St. Louis, returning Fri, Aug 29, priced at $232 found 4 days ago
Wed, Aug 27 - Sat, Aug 30
IAD
Washington
STL
St. Louis
$252 Roundtrip, found 4 days ago
$252
Roundtrip
found 4 days ago
Select United flight, departing Wed, Aug 27 from Washington to St. Louis, returning Sat, Aug 30, priced at $252 found 4 days ago
Tue, Oct 28 - Wed, Oct 29
IAD
Washington
STL
St. Louis
$254 Roundtrip, found 2 days ago
$254
Roundtrip
found 2 days ago
Select United flight, departing Tue, Oct 28 from Washington to St. Louis, returning Wed, Oct 29, priced at $254 found 2 days ago
Thu, Aug 28 - Sun, Aug 31
IAD
Washington
STL
St. Louis
$257 Roundtrip, found 6 days ago
$257
Roundtrip
found 6 days ago
Select United flight, departing Thu, Aug 28 from Washington to St. Louis, returning Sun, Aug 31, priced at $257 found 6 days ago

Frequently asked questions

Can I catch a flight from Washington Dulles Intl. Airport (IAD) to Lambert Field right now?
It's wise to learn about any travel advice reports and quarantine requirements in place in your destination. Ensure you check out the Covid-19 Travel Advisor for up-to-date info on catching a flight to STL.
What terminal is United Airlines at Washington Dulles Intl. Airport (IAD)?
While it's hard to say exactly which terminal your United Airlines flight from Washington Dulles Intl. Airport (IAD) to Lambert-St. Louis Intl. Airport (STL) will board from, we can tell you that it's highly likely you'll be getting off the plane at terminal 1.
Are there United Airlines non-stop flights from IAD to STL?
You bet. Save time and energy and fly straight from IAD to St. Louis Lambert International Airport with United Airlines. Avoid complicated transfers, lessen the risk of losing your luggage and begin your vacation faster — direct flights are preferred by many wise travelers.
How long is a United Airlines flight from IAD to STL?
If weather conditions are good and things go according to plan, your United Airlines flight from IAD to STL will take about 3 hours and 1 minute. Make use of that time to go over the details of your travel schedule before you hit the tarmac.
What type of aircraft does United Airlines fly from IAD to STL?
United Airlines commonly uses either the Canadair (Bombardier) Regional Jet 550 or the Embraer ERJ on the flight path between IAD and STL.
How many direct and indirect flights does United Airlines fly from IAD to STL?
If you're thinking about a journey from IAD to STL, you can select from at least 3 United Airlines flights each day.
If I am not able to travel due to COVID-19, can I change my booking to a later date?
For more info about changing your flight to STL, please visit our Customer Service Portal.
What is the best day to buy a plane ticket?
This just in! Airfares offered on Thursdays tend to be the cheapest, according to flight demand on Travelocity in 2021. Tuesday and Wednesday prices are also good, but you may want to prepare your budget if booking during the weekend, as data shows that is when prices are generally at their highest.
What are the cheapest days to fly?
Frequent travelers may already know this, but earlier in the week can be the cheapest time to fly. In 2021, flights departing on a Monday were generally the cheapest of the week, whereas you may pay a premium for weekend flights when demand is usually high. On average, tickets were most expensive for Saturday departures, so if you need to fly out on a weekend, you might look for deals ahead of time.
How far in advance can you book a flight?
Trying to figure out how early you should book your flight? It's possible to start comparing international airfares on Travelocity up to 12 months in advance. However, it does depend on the carrier as not all airlines release their prices that far out. According to our 2021 flight demand trends, last minute planners can still bag a bargain with some of the cheapest fares appearing 0-2 weeks prior to their travel dates.*According to flight demand on Travelocity.com from January to December 2021. Savings are subject to change based on departure location, date and destination.

Discover our best United flight from Washington IAD to St. Louis STL 

To find the best deals on flights to Washington from St. Louis with United, just enter your travel dates, filter by United, and hit search. You’ll find 2 flights to choose from and can sort by price, flight duration, and arrival or departure time.  

 

Return flights from Washington IAD to St. Louis STL with United 

If you’re planning a round trip, booking return flights with United is usually the most cost-effective option. With airfares ranging from $216 to $257, it’s easy to find a flight that suits your budget. Prices and availability subject to change. Additional terms may apply. 

 

Book one-way United flights from Washington IAD to St. Louis STL 

A one-way ticket gives you much greater flexibility—allowing you to choose your return date, destination, and time whenever you’re ready. By booking in advance you can find great deals on one-way tickets too. Right now, a one-way United flight from Washington to St. Louis costs from $112. Prices and availability subject to change. Additional terms may apply. 

 

The easy way to find cheap flights to St. Louis STL from  Washington IAD with United 

To find a cheap United flight from Washington IAD to St. Louis STL, sort your search results by price or filter by budget. Thanks to Travelocity’s Price Match Promise, if you find a better airfare deal anywhere else within 24 hours, we’ll credit or refund the difference. 

 

How to find our best airfare deals on United flights from Washington IAD to St. Louis STL 

If you’re looking for cheap flights, it helps to be flexible when it comes to your travel dates. You’ll usually find lower cost tickets when you travel during quieter months such as August, or if you book a flight with a stopover. 

 

Find nonstop flights from Washington IAD to St. Louis STL with United 

If you’re keen to be on St. Louis soil fast, don’t waste time with a stopover—filter your search results to show direct United flights only. The journey takes around 0 hour(s) 19 min(s) – so you’ll be there before you know it. 

 

Flexible airline tickets for United flights from Washington IAD to St. Louis STL 

Make sure you’re not out of pocket if plans change by choosing a flexible ticket with penalty-free amendment and cancellation options. Use our ‘no change fee’ filter to see which flights have this option.  

 

There are a lot of reasons to book your flights to St. Louis STL from  Washington IAD with United on Travelocity 

At Travelocity our vast and up-to-the-minute inventory puts all of our best flight deals in one place. So, whether you’re traveling on business or jetting off with friends and family, you can trust Travelocity to get you there.

United Airports
Hop on a(n) United flight today by flying to many destinations out of these domestic and international airports:
Airport code
Country
Airport name
Number of flights
ORDUSAO'Hare Intl.227
DENUSADenver Intl.226
IAHUSAGeorge Bush Intercontinental136
IADUSAWashington Dulles Intl.100
SFOUSASan Francisco Intl.64
LAXUSALos Angeles Intl.23
EWRUSALiberty Intl.20
FRADEUFrankfurt Intl.19
NRTJPNNarita Intl.19
PEKCHNCapital Intl.16

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Lowest nightly price found within the past 24 hours based on a 1 night stay for 2 adults. Prices and availability subject to change. Additional terms may apply.
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