AED240 Cheap Flights from St. Louis (STL) to Washington (IAD)

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

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

Prices were available within the past 7 days and start at AED240 for one-way flights and for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Frequently asked questions

How long does it take to fly from Lambert Field to Washington Dulles Intl. Airport (IAD)?
Book a seat with United Airlines and you'll be in the air for approximately 2 hours and 10 minutes. This sought-after carrier has a direct flight that takes off at 8:27AM from Lambert Field and comes in to land at Washington Dulles Intl. Airport (IAD) at 11:37AM. Expedia has some incredible flight deals, so take a look at what's on offer on this route today.
Is it cheaper to buy a plane ticket from Lambert-St. Louis Intl. Airport (STL) to Dulles Intl. Airport last minute?
When it's time to book your flights, being organized pays off. While it's possible to pick up a last-minute deal on a STL to IAD flight, prices usually don't get cheaper as the departure date nears. Based on flight pricing and demand studies in 2022, we have found that the sweet spot to book a domestic flight is between 28 – 35 days in advance. For international flights it's between three and four months.
What airline has the least delays from Lambert Field to IAD?
Travel with United Airlines from STL to Washington Dulles Intl. Airport (IAD) and there's a good chance you'll land at the time listed on your ticket. This airline clinches first place on this route, with 98% of flights arriving on time. If your flight is delayed, the free Expedia App is a good way to stay in the loop. Our useful app provides immediate trip notifications, from flight delays to gate changes.
What airports do you fly into for Washington from St. Louis?
From St. Louis, you can get to Washington through Washington Dulles Intl. Airport (IAD), Ronald Reagan Washington National Airport (DCA) and Baltimore Washington Intl. Thurgood Marshall Airport (BWI). Check which terminal is more convenient for you before making your decision. If you decide on Washington Dulles Intl. Airport (IAD), it's about 40 kilometers west of the center of the city. Use the money you save when booking your seat with Expedia to visit the city's awesome sights, such as White House and United States Capitol.
What are the most popular departure times for flights from Lambert Field to Washington Dulles Intl. Airport (IAD)?
For United Airlines flights making their way from Lambert Field to IAD, the busiest period is between 1:00 PM - 2:00 PM. If you want to avoid delays, fly in the morning. This allows you to avoid air traffic that accumulates later in the day.
Can I change the date of my flight from STL to Washington Dulles Intl. Airport (IAD)?
Quickly and easily make changes to your Lambert Field to IAD journey by logging in to the Expedia Trips portal. But before you make any amendments, read the ticket rules in your itinerary to find out what you're allowed to do and what fees apply for changes. Some airlines have a change fee per person, plus any difference in prices. However, if you booked in the last 24 hours, you may be able to cancel for free and arrange new flights. You can also visit our Customer Service portal for more handy information and to connect with our Virtual Agent.

Travel information

Origin airport
Lambert-St. Louis Intl.
Destination airport
Washington Dulles Intl.
Distance
1111 km
Average flight time
3 hours 7 mins

Book with confidence

St. Louis to Washington Flights

Whether you’re looking for a grand adventure or just want to get away for a last-minute break, flights from St. Louis to Washington offer the perfect respite. Not only does exploring Washington provide the chance to make some magical memories, dip into delectable dishes, and tour the local landmarks, but the cheap airfare means you won’t bust your budget. So no matter whether your ideal itinerary involves flying one way, non-stop, or round trip, you’re bound to find flights that match your schedule on Expedia, and at prices that won’t shock your wallet.

Bagging a cheap flight from St. Louis to Washington may mean more dollars to spend on for one-of-a-kind souvenirs when you arrive, but it doesn’t mean you have to skimp on your travel experience, as Expedia offers a sizzling selection of cheap airlines that’ll put you in your happy place on their planes, whether that’s getting lost in a hair-raising airport thriller, dreaming on the passing landscape over a glass of bubbly, or jotting down your vacation bucket list at 38,000 feet. There’s also bound to be plenty of opportunities to snap a few photos of the high life that will make your friends green with envy. After all, enjoying the journey is part of the fun.

With so many affordable flights and so many wonderful adventures awaiting you, there’s no reason to put off booking a fantastic flight from to today. So don’t leave it to the last minute to make your dream trip a reality: pack your bags with your go-to travel accessories, put together your list of must-see attractions and can’t-miss activities, and get ready to broaden your horizons – with Expedia, the wonders of Washington are only a plane trip away. Book your travel arrangements with us today!

If you would like to book flights to Washington more flexibly many prefer to purchase one-way tickets with options to take different airlines. A one way ticket to Washington is AED240 now!

St. Louis to Washington Flights

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