Cheap Flights from Washington (IAD) to St. Louis (STL)

View AU$189 flight on Sat, 10 May 2025Opens in a new window

Popular airlines from Washington Dulles International Airport (IAD) to Lambert-St. Louis International Airport (STL)

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Cheap Flights from Washington (IAD) to St. Louis (STL)

Prices were available within the past 7 days for one-way flights and round trip tickets for the period specified. Prices and availability are subject to change. Additional terms apply.

Delta
Sat., 10 May - Sat., 17 May
IAD
Washington
STL
St. Louis
AU$426 Return, found 6 days ago
AU$426
Return
found 6 days ago
Select Delta flight, departing Sat., 10 May from Washington to St. Louis, returning Sat., 17 May, priced at AU$426 found 6 days ago
Delta
Sat., 10 May - Sat., 17 May
IAD
Washington
STL
St. Louis
AU$433 Return, found 6 days ago
AU$433
Return
found 6 days ago
Select Delta flight, departing Sat., 10 May from Washington to St. Louis, returning Sat., 17 May, priced at AU$433 found 6 days ago
American Airlines
Sat., 10 May - Sat., 17 May
IAD
Washington
STL
St. Louis
AU$473 Return, found 6 days ago
AU$473
Return
found 6 days ago
Select American Airlines flight, departing Sat., 10 May from Washington to St. Louis, returning Sat., 17 May, priced at AU$473 found 6 days ago
United
Sat., 10 May - Sat., 17 May
IAD
Washington
STL
St. Louis
AU$482 Return, found 6 days ago
AU$482
Return
found 6 days ago
Select United flight, departing Sat., 10 May from Washington to St. Louis, returning Sat., 17 May, priced at AU$482 found 6 days ago
Delta
Sat., 10 May - Sat., 17 May
IAD
Washington
STL
St. Louis
AU$489 Return, found 6 days ago
AU$489
Return
found 6 days ago
Select Delta flight, departing Sat., 10 May from Washington to St. Louis, returning Sat., 17 May, priced at AU$489 found 6 days ago
Delta
Sat., 10 May - Sat., 17 May
IAD
Washington
STL
St. Louis
AU$506 Return, found 6 days ago
AU$506
Return
found 6 days ago
Select Delta flight, departing Sat., 10 May from Washington to St. Louis, returning Sat., 17 May, priced at AU$506 found 6 days ago
United
Sat., 10 May - Sat., 17 May
IAD
Washington
STL
St. Louis
AU$512 Return, found 6 days ago
AU$512
Return
found 6 days ago
Select United flight, departing Sat., 10 May from Washington to St. Louis, returning Sat., 17 May, priced at AU$512 found 6 days ago
Delta
Sat., 10 May - Sat., 17 May
IAD
Washington
STL
St. Louis
AU$534 Return, found 6 days ago
AU$534
Return
found 6 days ago
Select Delta flight, departing Sat., 10 May from Washington to St. Louis, returning Sat., 17 May, priced at AU$534 found 6 days ago
Delta
Sat., 10 May - Sat., 17 May
IAD
Washington
STL
St. Louis
AU$536 Return, found 6 days ago
AU$536
Return
found 6 days ago
Select Delta flight, departing Sat., 10 May from Washington to St. Louis, returning Sat., 17 May, priced at AU$536 found 6 days ago
United
Sat., 10 May - Sat., 17 May
IAD
Washington
STL
St. Louis
AU$537 Return, found 6 days ago
AU$537
Return
found 6 days ago
Select United flight, departing Sat., 10 May from Washington to St. Louis, returning Sat., 17 May, priced at AU$537 found 6 days ago
Flight from Washington to St. Louis route information
Origin airport
Washington Dulles Intl.
Destination airport
Lambert-St. Louis Intl.
Return price
AU$426
Distance
1111 km

Your quick guide to flights from Washington to St. Louis

Pick up great flights from Washington to St. Louis

With Expedia, you have your pick of flights a day with 20 airlines covering flights from Washington to St. Louis. Whether you’re on a business trip, a family holiday or a luxury break, just enter your travel dates, hit search then check out your choice of flights. Select from return, one way or multi-city flights, and use the advance search tool if you want a direct or refundable flight. You can narrow your search to show you just your preferred cabin class and airline, too. It’s all easy. You can book direct flights from Washington to St. Louis that take around hours.

Find cheap flights from Washington to St. Louis

From the great flight deals with prices currently ranging from AU$426 to AU$537, you can choose to see the cheapest flights first. Generally, you can book the cheapest flights from Washington to St. Louis around 4 to 6 weeks in advance. If your travel dates are flexible, try to avoid weekends and peak seasons – when you are more likely to grab the lowest prices. Even last minute, there are some impressive deals. The cheapest time to fly to St. Louis is normally in May.

Reasons to book your flight from Washington to St. Louis with Expedia

Expedia makes it easy to find, book, and travel, with everything you need all in one place. When you enter your travel details, find fantastic deals just for you on flight tickets from Washington to St. Louis across all the main airline carriers, so you can save time, dollars, and hassle finding the perfect flight. If you think your plans could change, choose refundable flights so any changes won’t cost you more. Book your flight to St. Louis right now and, if you join Expedia Rewards, you earn points this time and every time you travel with Expedia.

Frequently asked questions

How much is a flight from Dulles Intl. Airport to Lambert-St. Louis Intl. Airport (STL)?
Round-trip tickets from IAD to St. Louis Lambert International Airport start from AU$426. This price is based on fares listed within the last 7 days on Expedia for flights departing within the next year — make your booking ASAP so you don’t miss out. Prices and availability are subject to change. Additional terms apply.
Do I need to pay a cancellation fee if I cancel my flight from IAD to Lambert-St. Louis Intl. Airport (STL)?
When it comes to cancellation fees, every airline has its own terms and conditions. If you decide to cancel your holiday, head to our Customer Service Portal.
How do I find cheap flights from IAD to Lambert-St. Louis Intl. Airport (STL) that have flexible change policies?
Many airlines offer the option to reschedule your flight without a change fee. All you pay is the difference between the original flight and the new flight. When you’re searching for Dulles Intl. Airport to Lambert Field flights, you’ll see a “no change fees” filter for you to select.
How far is the flight from IAD to STL?
The distance from Dulles Intl. Airport (IAD) to Lambert-St. Louis Intl. Airport (STL) (STL) is just 1 100 kilometres. You’ll be stepping off the plane and grabbing your bags from the carousel before long.
Which airlines fly direct from Dulles Intl. Airport to Lambert Field?
A popular option with many travellers, United Airlines (UA) operates 60 monthly flights from IAD to STL. Pick the one that fits with your travel plans and book your fare today.
Are Dulles Intl. Airport to Lambert-St. Louis Intl. Airport (STL) flight tickets cheaper when they're purchased at the last minute?
Last-minute bookings from Washington Dulles Intl. Airport (IAD) to STL can be hit-or-miss. It is possible to score a bargain, but you could also miss out entirely! If you’d prefer to play it safe and start your travel planning early on, Expedia compares flight deals up to 12 months in advance. Just bear in mind that not all airlines issue their prices that far in advance. Our top tip? Check back often as updates are made frequently.

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