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$59 Cheap Flights from Washington (IAD) to St. Louis (STL)

View $59 flight on Wed, Nov 18, 2026Opens in a new window

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

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

Prices were available within the past 7 days and start at $59 for one-way flights and $170 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Frontier Airlines
Wed, Nov 11 - Mon, Nov 16
IAD
Washington
STL
St. Louis
$170 Roundtrip, found 1 day ago
$170
Roundtrip
found 1 day ago
Select Frontier Airlines flight, departing Wed, Nov 11 from Washington to St. Louis, returning Mon, Nov 16, priced at $170 found 1 day ago
Frontier Airlines
Mon, Oct 5 - Wed, Oct 14
IAD
Washington
STL
St. Louis
$176 Roundtrip, found 22 hours ago
$176
Roundtrip
found 22 hours ago
Select Frontier Airlines flight, departing Mon, Oct 5 from Washington to St. Louis, returning Wed, Oct 14, priced at $176 found 22 hours ago
Frontier Airlines
Tue, Dec 1 - Mon, Dec 7
IAD
Washington
STL
St. Louis
$182 Roundtrip, found 2 days ago
$182
Roundtrip
found 2 days ago
Select Frontier Airlines flight, departing Tue, Dec 1 from Washington to St. Louis, returning Mon, Dec 7, priced at $182 found 2 days ago
Frontier Airlines
Fri, Oct 2 - Wed, Oct 7
IAD
Washington
STL
St. Louis
$187 Roundtrip, found 23 hours ago
$187
Roundtrip
found 23 hours ago
Select Frontier Airlines flight, departing Fri, Oct 2 from Washington to St. Louis, returning Wed, Oct 7, priced at $187 found 23 hours ago
Frontier Airlines
Wed, Sep 23 - Wed, Oct 7
IAD
Washington
STL
St. Louis
$188 Roundtrip, found 2 days ago
$188
Roundtrip
found 2 days ago
Select Frontier Airlines flight, departing Wed, Sep 23 from Washington to St. Louis, returning Wed, Oct 7, priced at $188 found 2 days ago
Frontier Airlines
Mon, Nov 23 - Mon, Dec 7
IAD
Washington
STL
St. Louis
$189 Roundtrip, found 2 days ago
$189
Roundtrip
found 2 days ago
Select Frontier Airlines flight, departing Mon, Nov 23 from Washington to St. Louis, returning Mon, Dec 7, priced at $189 found 2 days ago
Delta
Mon, Oct 12 - Wed, Oct 14
IAD
Washington
STL
St. Louis
$201 Roundtrip, found 1 day ago
$201
Roundtrip
found 1 day ago
Select Delta flight, departing Mon, Oct 12 from Washington to St. Louis, returning Wed, Oct 14, priced at $201 found 1 day ago
American Airlines
Thu, Oct 15 - Fri, Oct 16
IAD
Washington
STL
St. Louis
$229 Roundtrip, found 1 day ago
$229
Roundtrip
found 1 day ago
Select American Airlines flight, departing Thu, Oct 15 from Washington to St. Louis, returning Fri, Oct 16, priced at $229 found 1 day ago
United
Thu, Oct 22 - Mon, Oct 26
IAD
Washington
STL
St. Louis
$275 Roundtrip, found 7 hours ago
$275
Roundtrip
found 7 hours ago
Select United flight, departing Thu, Oct 22 from Washington to St. Louis, returning Mon, Oct 26, priced at $275 found 7 hours ago
Alaska Airlines
Wed, Oct 14 - Wed, Oct 21
IAD
Washington
STL
St. Louis
$814 Roundtrip, found 14 hours ago
$814
Roundtrip
found 14 hours ago
Select Alaska Airlines flight, departing Wed, Oct 14 from Washington to St. Louis, returning Wed, Oct 21, priced at $814 found 14 hours ago

Alternative airports near St. Louis

Prices were available within the past 7 days. Prices and availability are subject to change.

Select flight to Lambert-St. Louis Intl. STL. Cheapest option available. Average driving time to city center is 20 minutes. Flights from $327
STL
Lambert-St. Louis Intl.
Cheapest
Average driving time to city center20 min
Flights from $327

What you need to know for your flight from Washington Dulles Intl. to Lambert-St. Louis Intl.

Washington (IAD) to St. Louis (STL) at a glance

Explore a range of options for flights from Washington Dulles International Airport (IAD) to Lambert-St. Louis International Airport (STL) on this domestic short-haul route. Whether you're looking for cheap flights from Washington or prefer full-service airlines, you can compare weekly flights to find the itinerary that aligns with your budget and travel plans. Get ready to discover the iconic sights and vibrant neighborhoods of St. Louis as you plan your journey.

  • Fastest flight duration: around 2h 30m non-stop
  • Route distance: roughly 700 miles (1,130 km)
  • Flights per week: around 12 departures on average
  • Typical fares (one-way): economy tickets often range from $100–$455, depending on seasonality and how far ahead you book

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

According to recent traveler bookings, here are the top airlines favored for flights from Washington to St. Louis, offering both non-stop and one-stop options. Popular layover spots include Hartsfield-Jackson Atlanta International Airport (ATL) with a layover of about 1 hour and 15 minutes, Charlotte-Douglas International Airport (CLT) at roughly 1 hour, and Detroit Metropolitan Wayne County Airport (DTW) with an approximate layover of 1 hour and 30 minutes. This variety allows you to mix and match price, total travel time, and cabin class to secure the best travel itinerary.

  • United: This full-service airline provides both non-stop and one-stop options, with one-way fares generally falling between $115 and $555. United operates around 54% of flights on this route, and the average non-stop flight duration is approximately 2 hours and 30 minutes.
  • Delta: As a full-service carrier, Delta offers one-stop flights with one-way ticket prices typically ranging from $100 to $425. It represents about 23% of departures along this route, featuring an in-flight time of 3 hours and 45 minutes, leading to a total travel time of around 5 hours, including layovers.
  • American Airlines: This carrier also provides one-stop service and has one-way fares that usually range from $130 to $415. American Airlines accounts for approximately 13% of departures on this route, with an in-flight duration of 3 hours and 45 minutes, resulting in a total journey time of about 5 hours, factoring in layovers.
  • Frontier Airlines: A budget-friendly option, Frontier Airlines offers one-stop services with one-way fares typically between $100 and $240. This airline makes up roughly 10% of departures on this route, with an in-flight time of 3 hours and 45 minutes, leading to an overall travel duration of around 5 hours, including layover times.

Travelers flying from Washington to St. Louis can enhance their journey by upgrading to first class or premium economy. Both United and Delta offer these premium cabin options to elevate your travel experience.

Best time to fly from Washington (IAD) to St. Louis (STL)

The most popular months for travelers flying from Washington to St. Louis are January, March, and April, when peak temperatures in St. Louis reach up to 56.1°F in April. If you prefer quieter travel, consider June, the least busy and relatively cheaper time to visit with fewer crowds and temperatures around 76.1°F. For better deals, May usually offers the lowest average one-way fare around $236. Flight availability peaks in May, with approximately 15 flights per week, making it easier to find convenient departure times. April has the fewest flights, with approximately 10 flights per week.

  • Cheapest time to fly: May usually offers good deals with average one-way fare around $236, roughly 8% cheaper than the yearly average.
  • More budget-friendly months to fly: October, June, and December typically offer average one-way fares roughly ranging from $237 to $250.
  • Most flight options: May has the highest number of flights from Washington to St. Louis, with approximately 15 flights per week, giving you more flexibility in scheduling your trip.
calendar iconMonthtemperature iconTemperaturecrowd level iconDemandflights iconWeekly Flightsprice iconAverage one-way Fare
January31.6°F (-0.2°C)Moderately High11$265
February34.9°F (1.6°C)Average11$261
March46.4°F (8.0°C)Moderately High11$270
April56.1°F (13.4°C)Moderately High10$257
May66.6°F (19.2°C)Average15$236
June76.1°F (24.5°C)Moderately Low11$245
July78.6°F (25.9°C)Moderately Low11$265
August77.0°F (25.0°C)Average13$253
September70.9°F (21.6°C)Average12$253
October58.6°F (14.8°C)Average13$237
November46.2°F (7.9°C)Moderately Low12$293
December37.8°F (3.2°C)Average12$250

*Average one-way fare is based on Expedia flight booking data from January 2025 to April 2026 for the specified route and travel class and may change depending on availability, dates, and demand.

Alternative route from Washington (IAD) to St. Louis (STL)

  • Washington to St. Louis (DCA-STL): Ronald Reagan Washington National Airport (DCA) is located approximately 23 miles from Washington Dulles International Airport (IAD). On this route, one-way economy prices generally fall between $90 and $400, influenced by the time of year and how far in advance you book. Passengers can choose from both non-stop and one-stop flight options. Major airlines operating this route include American Airlines and the budget-friendly Southwest Airlines. Additionally, first-class service is offered on this route.

How to find the best prices for flights from Washington (IAD) to St. Louis (STL)

Getting some of the best deals on flights from Washington to St. Louis is all about timing and flexibility. Here are some key tips to help you save:

  1. Best times to book and fly: cheaper fares are typically found when booking 2-8 weeks in advance, coinciding with when most travelers make their reservations. Morning departures between 5 a.m. and 12 p.m. tend to offer lower prices and are also the most popular flight times. Additionally, flying on Saturday usually provides cheaper options, while Thursday remains the most favored travel day.
  2. Set up price alerts: stay updated on price changes by using Expedia's Price Tracker. Receive alerts when fares drop for your selected route.
  3. Bundle and save: bundle your flight and hotel to save on Expedia, or unlock a hotel deal after booking your flight.*
  4. Compare flight options: use Expedia's search tool to compare airlines, routes, direct vs. non-direct flights, and flight times. You can also sort by price to find the most affordable options.
  5. Stay flexible with dates: being open to different travel days can sometimes help you find better prices on flights and hotels.
  6. Think about luggage: nowadays, it's important to check the airline's baggage policies to find the best value. That may be paying for an additional carry-on bag or booking a ticket with checked luggage included. Either way, double-check your allowance before confirming your booking to avoid excess baggage fees at the airport.

*Members only. Savings vary and are not available on all bundles. Select hotels.

Arriving at Lambert-St. Louis International Airport from Washington Dulles International Airport

St. Louis welcomes travelers from Washington with a range of transport options based on price, convenience, and proximity. For departures, Washington Dulles International Airport is roughly a 40-minute drive (covering about 29 miles) from central Washington. Here's how to reach St. Louis efficiently:

  • Hotel transfer: Transfers offer a convenient way to reach your hotel in St. Louis, with private rides that can be arranged in advance.
  • Car rental: Renting a car from Lambert-St. Louis International Airport is a great option if you plan to explore and sightsee beyond the city. Browse cheap car rentals at Lambert-St. Louis International Airport on Expedia.
  • Taxi/ride-hailing: Taxis and ride-hailing services may be available from designated pickup areas outside the terminal, check locally on arrival.
  • Public transportation: From Lambert-St. Louis International Airport, Lambert Main Terminal Station, a metro station, is located about 0.1 miles away on foot, providing convenient access to public transit.

Frequently asked questions

How much does a flight from Washington, DC (IAD-Washington Dulles Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) cost?
You can find cheap one-way flights from $59 and cheap return flights from $170 Washington, DC (IAD-Washington Dulles Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) with Expedia. One-way flights generally range between $154 and $657, and roundtrip flights usually range from $313 to $1119. Flight prices vary based on the month and day of the week you want to travel, as well as the airline and how far in advance you book your ticket. Filter your search on Expedia by "Price (lowest to highest)" to see the cheapest fares first, and use the Price Tracking tool to receive alerts when Washington, DC (IAD-Washington Dulles Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) ticket fares go up or down.*Typical price ranges based on flights available on Expedia in the last year. Prices include multi-airline options.
What is the cheapest month to fly from Washington, DC (IAD-Washington Dulles Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
September is the cheapest month to fly from Washington, DC (IAD) to St. Louis, MO (STL), with average return fares around $303. This fare is about 23% lower than the average price throughout the year, as travel demand tends to decrease after the summer. Other economical months include February and August.*Averages based on flights available on Expedia in the last year.
Which airlines fly direct from Washington, DC (IAD-Washington Dulles Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
United operates around 14 direct flights from IAD to STL every week.
What is the cheapest airline that flies from Washington, DC (IAD-Washington Dulles Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
United is one of the cheapest airlines offering nonstop flights from Washington Dulles Intl. (IAD) to Lambert-St. Louis Intl. (STL), with round-trip tickets starting from around $230. Use Expedia's search tool to compare the prices and schedules of airlines that fly this route to find the best option for your plans and budget.*Prices based on flights available on Expedia in the last year.
How do I find cheap flights from Washington, DC (IAD-Washington Dulles Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
To find a cheap flight from Washington, DC (IAD-Washington Dulles Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.), be flexible with your dates. Traveling outside of peak vacation months and booking a mid-week flight can help you save. Early morning and late night flights are often more affordable, too. Expedia allows you to compare flight times, airlines and routes all in one place to find low fares. You can also set up Price Tracking and receive alerts when fares go up or down.
What is the best airline to fly with from Washington, DC (IAD-Washington Dulles Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
The best airline to fly with from Washington, DC (IAD) to St. Louis, MO (STL) will differ from traveler to traveler. If you like to fly early, United offers early morning flights. If price is the most important factor, United typically offers the lowest fares. United also offers the most daily flights from IAD to STL, which is great if flexibility is what you value most. The best carrier for this journey could also be the one you have a loyalty membership with, as flying with that airline or another airline within the same alliance could help you collect points or enjoy lounge access.
What is the best time to fly from Washington, DC (IAD-Washington Dulles Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
The best time to fly from Washington, DC (IAD) to St. Louis, MO (STL) is typically in September or February. During these months, you can find return flights at around $303, making them the cheapest times to travel. September is particularly appealing as it offers pleasant weather and fewer crowds, while February often sees lower demand after the holiday season, allowing for better prices.*Prices based on flights available on Expedia in the last year.
How many flights per day from Washington, DC (IAD-Washington Dulles Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
On average, there are around 2 nonstop flights per day from Washington Dulles Intl. (IAD) to Lambert-St. Louis Intl. (STL). For more options, look at flights that include layovers.
What is the earliest flight from Washington, DC (IAD-Washington Dulles Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
The earliest flight from Washington Dulles International Airport (IAD) to Lambert-St. Louis International Airport (STL) usually leaves at around 5:00 AM, operated by American Airlines. An early departure like this can help you maximize your day in St. Louis. To compare early flights on Expedia, select the "Early Morning" and "Morning" filters in your search.
How long does it take to fly from Washington, DC (IAD-Washington Dulles Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
Flying nonstop from IAD to STL takes around 2 hours 30 minutes, with the route covering approximately 695 miles. Flights with a layover typically take 2 hours 20 minutes longer than direct options. Keep in mind that actual flight times can vary due to wind patterns, weather, and air traffic.
Can you fly business or first class from Washington, DC (IAD-Washington Dulles Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
First class seats are offered on the IAD to STL route. First class cabins are available on:

  • American Airlines
  • Delta Air Lines
  • United Airlines

How much is a business class flight from Washington, DC (IAD-Washington Dulles Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
A direct, return business class ticket from Washington, DC (IAD) to St. Louis (STL) typically costs between $1,254 - $1,621. A non-stop, one-way business class flight is usually around $464 - $479. Prices often fluctuate based on seasonality and how early you book. You may also be able to find a cheaper business class journey between Washington, DC (IAD-Washington Dulles Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) if you opt for a connecting flight.*Prices based on flights available on Expedia in the last year.
How do I earn miles on a Washington, DC (IAD-Washington Dulles Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) flight with Expedia?
It's easy to earn miles on a Washington, DC (IAD-Washington Dulles Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) flight when you book with Expedia. Before you confirm your booking, simply select your frequent flyer program and enter your program number. As a member of One Key™, you can also earn OneKeyCash™* on top of your airline miles when you book with Expedia.*Excludes taxes and fees. OneKeyCash is not redeemable for cash and can only be used on Expedia and other participating brands.
What airports do you fly into for St. Louis from Washington Dulles Intl. (IAD)?
From Washington Dulles Intl. (IAD), you can fly into Lambert-St. Louis Intl. (STL) to reach St. Louis. Some flights may connect through major hubs like Denver Intl. (DEN), Charlotte-Douglas Intl. (CLT), Liberty Intl. (EWR) before reaching St. Louis. Compare routes and airports on Expedia to find the best flight options for your travel plans.
Is it cheaper to buy a plane ticket from Washington, DC (IAD-Washington Dulles Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) at the last minute?
Typically, booking a last minute flight from Washington, DC (IAD-Washington Dulles Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) will be more expensive than booking in advance. As the departure date approaches, there are usually fewer seats available which can drive up the cost. However, if there's some wiggle room with your travel dates and times, you could bag a cheap last-minute fare.
Is it cheaper to book a Washington, DC (IAD-Washington Dulles Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) flight and hotel package?
Securing a Washington, DC (IAD-Washington Dulles Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) St Louis Vacation Packages is usually cheaper than booking separately. With Expedia, you can enjoy the ease of organizing your travels all in one place. Select from our extensive range of stays and then add flights, activities and car rentals to your booking. Bundle everything together, and you could save hundreds of dollars.
Can I cancel or change the date of my flight from Washington, DC (IAD-Washington Dulles Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
If you booked your Washington, DC (IAD-Washington Dulles Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) flight within the last 24 hours, you may be able to modify or cancel it without any fees. Depending on the airline and the type of ticket you have, additional charges may apply for changes beyond this timeframe. Airline policies and contact information can be found in your itinerary or confirmation email. Or, head to our Customer Service portal if you'd like more information.

Travel information

Origin airport
Washington Dulles Intl.
Destination airport
Lambert-St. Louis Intl.
Airlines serving
Alaska Airlines, American Airlines, Delta, Frontier Airlines, United
Roundtrip price
$170
Distance
694 mi
Average flight time
1 hour 20 mins

Book with confidence

Washington to St. Louis Flights

The cheapest times to fly from Washington to St. Louis

On average, Thursday can be the cheapest time to fly, according to data from the Airlines Reporting Corporation (ARC), one of the world's biggest databases for global airline sales. The data reveals that you could save up to 16% by flying on a Thursday—the cheapest day to travel on average—instead of a Sunday—the most expensive. Some of the most affordable flights from Washington to St. Louis are during the month of November. You can find some of the cheapest flights from Washington to St. Louis with Expedia's search tool and vast selection of airlines.

 

The best time to book a flight from Washington to St. Louis

Sunday is one of the best days to book for cheap flights from Washington to St. Louis: Tickets reserved on a Sunday cost between 6% and 13% less than those reserved on a Friday, according to ARC data. The data also suggests booking early can also lead to cheaper airfares. You could save 24% by buying your tickets for domestic flights at least a month in advance and 10% by booking international flights 2 months in advance.

 

How to find cheap round-trip tickets from Washington to St. Louis

Being flexible with your dates and using Expedia's Price Drop Protection and Price Tracking features are some of the best ways of finding a cheap ticket from Washington to St. Louis in 2026. You can also book with separate airlines for your outbound and return journeys, from $59 one-way. Expedia also offers Price Drop Protection, so if the cost of your airfare goes down after booking, you'll receive a credit for the difference*. This is available for a small fee, and is free to One Key Gold and Platinum tier members.

 

Expedia's Price Tracking feature means you can stay on top of airfares without manually checking every day. It sends you automated price alerts for cheap Washington to St. Louis flights and uses historical data to indicate when the best time to book is. Download Expedia's free app to activate this handy tool in a few easy taps.

 

You could also save big by booking one of Expedia's vacation packages. Bundling together your Washington to St. Louis airfare with your accommodations and car rental is often cheaper than booking everything separately. There’s also One Key, Expedia's generous rewards program. Join for free and you could earn One Key cash on most bookings to save on future adventures.

 

*Terms apply.

 

Disclaimer: ARC The statistics are based on average round-trip ticket prices between January and August 2023. The percentages you see are averages.

 

Washington to St. Louis Flights

*Flight schedules are subject to change.

*Available to One Key members.

 

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