What are the cheapest airlines flying from Washington, D.C. Dulles Intl Airport to St. Louis round-trip?

Cheapflights users have booked flights from Washington, D.C. Dulles Intl Airport to St. Louis round-trip from $217. Other airlines that can offer you cheap pricing are United Airlines, from $227, and Frontier, from $240. These flights start at 48% lower than the current average price 3 months from now.

What are the cheapest airlines to fly from Washington, D.C. Dulles Intl Airport to St. Louis one-way?

The cheapest airlines for a one-way flight from Washington, D.C. Dulles Intl Airport to St. Louis are United Airlines ($89), Southwest ($104), and Delta ($109).

What are the cheapest flights from Washington, D.C. Dulles Intl Airport to St. Louis?

Looking for the cheapest flight from Washington, D.C. Dulles Intl Airport to St. Louis? While on average our users pay $399, our data indicates the cheapest price to be $114. The most popular route (Washington, D.C. Dulles Intl - Lambert-St Louis), is priced around $197.

What are the most reliable airlines from Washington, D.C. Dulles Intl Airport to St. Louis?

Consider GoJet (84%), Avianca (84%) or Copa Airlines (84%) when booking your flight. These represent the most reliable airlines when flying from Washington, D.C. Dulles Intl Airport to St. Louis.

What are the most popular airlines that fly from Washington, D.C. Dulles Intl Airport to St. Louis?

American Airlines, Delta and United Airlines are the most popular airlines when flying from Washington, D.C. Dulles Intl Airport to St. Louis.

What is the cheapest day to fly round-trip from Washington, D.C. Dulles Intl Airport to St. Louis?

Users have found that leaving on a Saturday can be a cost-effective option. It’s possible to save up to 30% on your flight compared to booking on days when demand is much higher.

What is the cheapest month to fly from Washington, D.C. Dulles Intl Airport to St. Louis?

The best pricing can be found in the month of August. Prices to St. Louis from Washington, D.C. Dulles Intl Airport average $327. You can even find prices in August for less than $327, as users have found deals to St. Louis from as low as $185. The month of March appears to be one of the more expensive times to travel to St. Louis from Washington, D.C. Dulles Intl Airport. Flying in the targeted month can save you up to 15%.

Most accurate provider : When it comes to deals on Washington, D.C. Dulles Intl Airport-St. Louis flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Washington, D.C. Dulles Intl Airport-St. Louis flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Washington, D.C. Dulles Intl Airport-St. Louis flight searches over the past month and is updated monthly.

Most trusted provider : When it comes to deals on Washington, D.C. Dulles Intl Airport-St. Louis flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Washington, D.C. Dulles Intl Airport-St. Louis flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

What airport do you fly into for flights to St. Louis from Washington, D.C. Dulles Intl?

If you book a flight to St. Louis from Washington, D.C. Dulles Intl, you will be flying to Lambert-St Louis, which is the city’s only airport. Lambert-St Louis (STL) is located 12.7 mi from the center of St. Louis. There are 7 flights from Washington, D.C. Dulles Intl to Lambert-St Louis per day from 3 different airlines.

Can I find deals for flights from Dulles Intl to St. Louis that include hotel bookings?

Yes. In addition to deals on Dulles Intl to St. Louis flights, Cheapflights offers vacation packages that include both flights and hotel.

How can I find direct flights from Dulles Intl to St. Louis?

After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Dulles Intl to St. Louis.

Can I find deals for business class flights from Dulles Intl to St. Louis?

Yes. Cheapflights offers flight deals from Dulles Intl to St. Louis by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

$89+ Flights from Washington, D.C. Dulles Intl Airport to St. Louis

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1. Tell us where you want to go

Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”

2. Select your favorite providers

We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.

3. Compare prices and book

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Cheapflights Tip: The best prices from Washington, D.C. Dulles Intl to Lambert-St Louis are usually found in February or July, booked 70 days in advance, depart on a Sunday or Tuesday and return on a Friday

Cheap flight deals from Dulles Intl to St. Louis

Most accurate provider	FlightHub 3 stars
Most trusted provider	FlightHub 3 stars
Round-trip from	$217 (Delta)
One-way from	$89 (United Airlines)
Popular in	December
Cheapest in	February
Average price	$394
Good round-trip deal	$373 or less
Good one-way deal	$149 or less

Provider with most accurate pricing for Washington, D.C. Dulles Intl-Lambert-St Louis flight deals.

Search Deals

Provider most trusted by Cheapflights users for Washington, D.C. Dulles Intl-Lambert-St Louis flights.

Search Deals

From Washington, D.C. Dulles Intl to Lambert-St Louis

Search Deals

One-way flight from Washington, D.C. Dulles Intl to Lambert-St Louis

Search Deals

Highest demand for flights based on searches. 8% potential increase in price ($38 potential increase over avg. RT price).

Search Deals

Cheapest flight prices on average. 1% potential price decrease ($8 potential savings vs. average RT price).

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Average for round-trip flights in March 2025

Search Deals

Price to beat on a round-trip flight from Washington, D.C. Dulles Intl to Lambert-St Louis.

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Price to beat on a one-way flight from Washington, D.C. Dulles Intl to Lambert-St Louis.

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Find flight deals from Dulles Intl to St. Louis

Cheapest flights from Dulles Intl to St. Louis
Explore the most affordable flight options available from Dulles Intl to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on March 21, 2025.

Sat 5/36:00 amIAD - STL

1 stop4h 47mDelta

Mon 5/57:01 pmSTL - IAD

1 stop4h 27mDelta

Deal found 3/21

$217

Fri 7/48:30 amIAD - STL

1 stop4h 57mUnited Airlines

Sun 7/135:27 pmSTL - IAD

1 stop6h 03mUnited Airlines

Deal found 3/21

$224

Tue 7/226:10 amIAD - STL

1 stop8h 39mFrontier

Tue 8/52:52 pmSTL - IAD

1 stop8h 11mFrontier

Deal found 3/20

$240

Thu 4/105:00 amIAD - STL

1 stop4h 30mAmerican Airlines

Fri 4/117:03 pmSTL - IAD

1 stop3h 53mAmerican Airlines

Deal found 3/20

$297

Sun 4/1311:51 amIAD - STL

1 stop8h 47mMultiple Airlines

Mon 4/144:57 pmSTL - IAD

1 stop23h 05mMultiple Airlines

Deal found 3/20

$319

Best flights from Dulles Intl to St. Louis
Discover carefully curated flight deals from Dulles Intl to St. Louis that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated March 21, 2025.

Sat 5/36:00 amIAD - STL

1 stop4h 47mDelta

Mon 5/57:01 pmSTL - IAD

1 stop4h 27mDelta

Deal found 3/21

$217

Fri 5/96:22 amIAD - STL

1 stop6h 57mUnited Airlines

Sat 5/108:25 amSTL - IAD

Nonstop2h 09mUnited Airlines

Deal found 3/20

$227

Tue 7/226:10 amIAD - STL

1 stop8h 39mFrontier

Tue 8/52:52 pmSTL - IAD

1 stop8h 11mFrontier

Deal found 3/20

$240

Wed 4/95:52 pmIAD - STL

1 stop6h 54mMultiple Airlines

Sat 4/126:45 pmSTL - IAD

1 stop15h 05mMultiple Airlines

Deal found 3/20

$248

Thu 4/105:00 amIAD - STL

1 stop4h 30mAmerican Airlines

Sun 4/137:19 amSTL - IAD

1 stop5h 23mAmerican Airlines

Deal found 3/20

$282

Last-minute flights from Dulles Intl to St. Louis
Discover last-minute flight deals from Dulles Intl to St. Louis. Data last updated March 21, 2025 and is based on user searches.

Wed 3/266:27 amIAD - STL

2 stops8h 24mAmerican Airlines

Wed 3/264:26 pmSTL - IAD

2 stops6h 32mAmerican Airlines

Deal found 3/20

$927

Thu 3/275:54 pmIAD - STL

1 stop6h 55mFrontier

Mon 3/315:24 pmSTL - IAD

1 stop22h 40mFrontier

Deal found 3/20

$268

Sat 3/296:00 amIAD - STL

1 stop4h 36mDelta

Mon 3/3110:30 amSTL - IAD

1 stop4h 53mDelta

Deal found 3/20

$539

Sun 3/308:35 amIAD - STL

Nonstop2h 23mUnited Airlines

Mon 3/318:25 amSTL - IAD

Nonstop2h 09mUnited Airlines

Deal found 3/21

$597

Tue 4/18:30 amIAD - STL

1 stop16h 16mFrontier

Sat 4/54:57 pmSTL - IAD

1 stop16h 58mFrontier

Deal found 3/20

$242

Wed 4/95:52 pmIAD - STL

1 stop6h 54mMultiple Airlines

Sat 4/126:45 pmSTL - IAD

1 stop15h 05mMultiple Airlines

Deal found 3/20

$248

Thu 4/105:00 amIAD - STL

1 stop4h 30mAmerican Airlines

Fri 4/117:03 pmSTL - IAD

1 stop3h 53mAmerican Airlines

Deal found 3/20

$297

Fri 4/115:29 pmIAD - STL

1 stop6h 46mUnited Airlines

Sun 4/138:25 amSTL - IAD

Nonstop2h 09mUnited Airlines

Deal found 3/20

$233

Thu 4/246:00 amIAD - STL

1 stop4h 36mDelta

Fri 4/257:01 pmSTL - IAD

1 stop4h 27mDelta

Deal found 3/20

$217

One-way flights from Dulles Intl to St. Louis
Search for one-way flight options from Dulles Intl to St. Louis. Find affordable one-way fares based on user searches. Data last updated March 21, 2025.

Thu 4/178:35 amIAD - STL

Nonstop2h 23mUnited Airlines

Deal found 3/20

$89

Tue 4/227:50 amIAD - STL

2 stops10h 55mSouthwest

Deal found 3/20

$104

Sat 4/197:35 amIAD - STL

1 stop5h 06mDelta

Deal found 3/20

$109

Tue 4/15:54 pmIAD - STL

1 stop6h 52mFrontier

Deal found 3/20

$120

Thu 5/1512:49 pmIAD - STL

1 stop23h 48mSun Country Air

Deal found 3/20

$128

Thu 5/155:02 amIAD - STL

1 stop4h 54mAmerican Airlines

Deal found 3/20

$134

Wed 4/238:25 amIAD - STL

3 stops33h 50mMultiple Airlines

Deal found 3/20

$152

Cheapflights Fare Finder

Use the filters below to find and compare flights from Washington, D.C. Dulles Intl Airport to St. Louis that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Washington, D.C.St. Louis

IAD - STL

IADSTL

Washington, D.C. Dulles Intl

Sat 5/3

6:00 am-9:47 am

1 stop4h 47m

Lambert-St Louis

Mon 5/5

7:01 pm-12:28 am

1 stop4h 27m

$217

Washington, D.C.St. Louis

IAD - STL

IADSTL

Washington, D.C. Dulles Intl

Fri 7/4

8:30 am-12:27 pm

1 stop4h 57m

Lambert-St Louis

Sun 7/13

5:27 pm-12:30 am

1 stop6h 03m

$224

Washington, D.C.St. Louis

IAD - STL

IADSTL

Washington, D.C. Dulles Intl

Tue 7/22

6:10 am-1:49 pm

1 stop8h 39m

Lambert-St Louis

Tue 8/5

2:52 pm-12:03 am

1 stop8h 11m

$240

Washington, D.C.St. Louis

IAD - STL

IADSTL

Washington, D.C. Dulles Intl

Thu 4/10

5:00 am-8:30 am

1 stop4h 30m

Lambert-St Louis

Sun 4/13

7:19 am-1:42 pm

1 stop5h 23m

$282

Washington, D.C.St. Louis

IAD - STL

IADSTL

Washington, D.C. Dulles Intl

Sun 4/13

11:51 am-7:38 pm

1 stop8h 47m

Lambert-St Louis

Mon 4/14

4:57 pm-5:02 pm

1 stop23h 05m

$319

Washington, D.C.St. Louis

IAD - STL

IADSTL

Washington, D.C. Dulles Intl

Thu 4/17

8:35 am-9:58 am

Nonstop2h 23m

$89

Washington, D.C.St. Louis

IAD - STL

IADSTL

Washington, D.C. Dulles Intl

Wed 4/23

12:29 pm-6:02 pm

1 stop6h 33m

$99

Washington, D.C.St. Louis

IAD - STL

IADSTL

Washington, D.C. Dulles Intl

Tue 4/22

7:50 am-5:45 pm

2 stops10h 55m

$104

Washington, D.C.St. Louis

IAD - STL

IADSTL

Washington, D.C. Dulles Intl

Wed 4/2

5:54 pm-11:46 pm

1 stop6h 52m

$120

Washington, D.C.St. Louis

IAD - STL

IADSTL

Washington, D.C. Dulles Intl

Thu 5/15

12:49 pm-11:37 am

1 stop23h 48m

$128

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/20

Showing 1-10 of 12 results

Compare providers for flights from Dulles Intl to St. Louis

Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Dulles Intl to St. Louis in March.

Provider	Price Accuracy	Trust Score*
Expedia	Price Accuracy1 star	Trust Score*3 stars
FlightHub	Price Accuracy3 stars	Trust Score*3 stars
eDreams	Price Accuracy3 stars	Trust Score*3 stars
Priceline	Price Accuracy1 star	Trust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

Most accurate provider: When it comes to deals on Washington, D.C. Dulles Intl Airport-St. Louis flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Washington, D.C. Dulles Intl Airport-St. Louis flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Washington, D.C. Dulles Intl Airport-St. Louis flight searches over the past month and is updated monthly.
Most trusted provider: When it comes to deals on Washington, D.C. Dulles Intl Airport-St. Louis flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Washington, D.C. Dulles Intl Airport-St. Louis flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

Best time to book a flight from Dulles Intl to St. Louis

Have a flexible travel schedule? Discover the best time to fly to St. Louis from Dulles Intl with our price prediction graph.

Estimated round-trip price

Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from Washington, D.C. Dulles Intl Airport to St. Louis

How far ahead should I book a flight from Washington, D.C. Dulles Intl Airport to St. Louis?

The best time to book flights from Washington, D.C. Dulles Intl Airport to St. Louis is 69 days before your desired departure date. The cost of your flight will likely increase significantly if you book two weeks in advance of your flight.

What is the cheapest month to book a flight from Washington, D.C. Dulles Intl Airport to St. Louis?

Currently, August is the cheapest month in which you can book a flight from Washington, D.C. Dulles Intl Airport to St. Louis (average of $311). Flying from Washington, D.C. Dulles Intl Airport to St. Louis in March is currently the most expensive (average of $356). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest time of day to fly from IAD to STL?

It’s typically best to fly out from Washington, D.C. Dulles Intl Airport to St. Louis in the evening. Doing so could potentially save you 39% on the flight price compared to flying in the afternoon, which is usually more expensive.

What is the cheapest day to fly from Washington, D.C. Dulles Intl Airport to St. Louis?

Travelers seeking maximum savings on their Washington, D.C. Dulles Intl Airport to St. Louis flight should consider departing on Wednesday at noon when fares are most often at their lowest. Tuesday afternoons flights should be avoided if possible as fares are typically the most expensive at this time.

Weekly flight availability from Washington, D.C. Dulles Intl Airport to St. Louis

The most flights from IAD to STL are scheduled on a Monday (7 on average). You will have fewer flight options on Monday, which is when the least amount of flights are scheduled (7 on average).

Rainfall in St. Louis by month

In terms of precipitation, rainfall in St. Louis ranges from 2.2 - 4.7 inches per month. May is typically the wettest month, when rainfall can reach 4.7 in. February is typically the driest time to visit St. Louis when rainfall is around 2.2 in.

Temperature in St. Louis by month

If weather is an important factor for your trip to St. Louis, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 80.6 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 32.0 F).

Reviews of airlines servicing St. Louis

Read reviews from past customers who have flown Southwest, Delta and United Airlines from Washington, D.C. to St. Louis. In addition to providing an overall rating, users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.

Southwest

8.1

Very good

4,278 reviews

Reviews

1 / 20

8.0

Excellent

Ila,Mar 2025

HOU - DAL

Our original flight was delayed. We were able to change our flight and got home at close to the same time. Looking forward to when you have assigned seating.

Southwest

8.1

Very good

4,278 reviews

Southwest

8.1

Very good

4,278 reviews

Reviews

1 / 20

8.0

Excellent

Ila,Mar 2025

HOU - DAL

Our original flight was delayed. We were able to change our flight and got home at close to the same time. Looking forward to when you have assigned seating.

Delta

8.0

Very good

7,895 reviews

Southwest

8.1

Very good

4,278 reviews

Reviews

1 / 20

8.0

Excellent

Ila,Mar 2025

HOU - DAL

Our original flight was delayed. We were able to change our flight and got home at close to the same time. Looking forward to when you have assigned seating.

United Airlines

7.4

Good

8,605 reviews

Southwest

8.1

Very good

4,278 reviews

Reviews

1 / 20

8.0

Excellent

Ila,Mar 2025

HOU - DAL

Our original flight was delayed. We were able to change our flight and got home at close to the same time. Looking forward to when you have assigned seating.

American Airlines

7.2

Good

10,000 reviews

Southwest

8.1

Very good

4,278 reviews

Reviews

1 / 20

8.0

Excellent

Ila,Mar 2025

HOU - DAL

Our original flight was delayed. We were able to change our flight and got home at close to the same time. Looking forward to when you have assigned seating.

Sun Country Air

6.9

Okay

348 reviews

Southwest

8.1

Very good

4,278 reviews

Reviews

1 / 20

8.0

Excellent

Ila,Mar 2025

HOU - DAL

Our original flight was delayed. We were able to change our flight and got home at close to the same time. Looking forward to when you have assigned seating.

Related info for your journey

What airport do you fly into for flights to St. Louis from Washington, D.C. Dulles Intl?
If you book a flight to St. Louis from Washington, D.C. Dulles Intl, you will be flying to Lambert-St Louis, which is the city’s only airport. Lambert-St Louis (STL) is located 12.7 mi from the center of St. Louis. There are 7 flights from Washington, D.C. Dulles Intl to Lambert-St Louis per day from 3 different airlines.
What are the cheapest airlines flying from Washington, D.C. Dulles Intl Airport to St. Louis round-trip?
Cheapflights users have booked flights from Washington, D.C. Dulles Intl Airport to St. Louis round-trip from $217. Other airlines that can offer you cheap pricing are United Airlines, from $227, and Frontier, from $240. These flights start at 48% lower than the current average price 3 months from now.
What are the cheapest airlines to fly from Washington, D.C. Dulles Intl Airport to St. Louis one-way?
The cheapest airlines for a one-way flight from Washington, D.C. Dulles Intl Airport to St. Louis are United Airlines ($89), Southwest ($104), and Delta ($109).
What are the most reliable airlines from Washington, D.C. Dulles Intl Airport to St. Louis?
Consider GoJet (84%), Avianca (84%) or Copa Airlines (84%) when booking your flight. These represent the most reliable airlines when flying from Washington, D.C. Dulles Intl Airport to St. Louis.
What are the cheapest flights from Washington, D.C. Dulles Intl Airport to St. Louis?
Looking for the cheapest flight from Washington, D.C. Dulles Intl Airport to St. Louis? While on average our users pay $399, our data indicates the cheapest price to be $114. The most popular route (Washington, D.C. Dulles Intl - Lambert-St Louis), is priced around $197.
Can I find deals for flights from Dulles Intl to St. Louis that include hotel bookings?
Yes. In addition to deals on Dulles Intl to St. Louis flights, Cheapflights offers vacation packages that include both flights and hotel.
How can I find direct flights from Dulles Intl to St. Louis?
After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Dulles Intl to St. Louis.
Can I find deals for business class flights from Dulles Intl to St. Louis?
Yes. Cheapflights offers flight deals from Dulles Intl to St. Louis by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.
What is the cheapest month to book a flight from Washington, D.C. Dulles Intl Airport to St. Louis?
Currently, August is the cheapest month in which you can book a flight from Washington, D.C. Dulles Intl Airport to St. Louis (average of $311). Flying from Washington, D.C. Dulles Intl Airport to St. Louis in March is currently the most expensive (average of $356). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

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Top 3 airlines flying from Dulles Intl to St. Louis

Airline	Cheapest	Average	Flexibility	On-time
Delta	Cheapest$198	Average$308	FlexibilityNo cancel fee	On-timeN/A
American Airlines	Cheapest$255	Average$366	FlexibilityNo cancel fee	On-time71%
United Airlines	Cheapest$265	Average$494	FlexibilityNo cancel fee	On-time69%

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$89+ Cheap flights from Dulles Intl (IAD) to St. Louis (STL)

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 4/17. Fares are subject to change and may not be available on all flights or dates of travel.

Find cheap flights from Dulles Intl to St. Louis with Cheapflights

1. Tell us where you want to go

2. Select your favorite providers

3. Compare prices and book

Cheapflights Tip: The best prices from Washington, D.C. Dulles Intl to Lambert-St Louis are usually found in February or July, booked 70 days in advance, depart on a Sunday or Tuesday and return on a Friday

Cheap flight deals from Dulles Intl to St. Louis

Most accurate provider

Most trusted provider

Round-trip from

One-way from

Popular in

Cheapest in

Average price

Good round-trip deal

Good one-way deal

Find flight deals from Dulles Intl to St. Louis

Cheapest flights from Dulles Intl to St. LouisExplore the most affordable flight options available from Dulles Intl to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on March 21, 2025.

Explore the most affordable flight options available from Dulles Intl to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on March 21, 2025.

Cheapflights Fare Finder

Use the filters below to find and compare flights from Washington, D.C. Dulles Intl Airport to St. Louis that are best for you.

Compare providers for flights from Dulles Intl to St. Louis

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.

Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Dulles Intl to St. Louis in March.

Best time to book a flight from Dulles Intl to St. Louis

Have a flexible travel schedule? Discover the best time to fly to St. Louis from Dulles Intl with our price prediction graph.

Cheapflights Insights

Everything you need to know about your flight from Washington, D.C. Dulles Intl Airport to St. Louis

How far ahead should I book a flight from Washington, D.C. Dulles Intl Airport to St. Louis?

Use this chart to determine the optimal time to book a round-trip flight from Dulles Intl to St. Louis. Price data was last updated on March 14, 2025.

What is the cheapest month to book a flight from Washington, D.C. Dulles Intl Airport to St. Louis?

What is the cheapest time of day to fly from IAD to STL?

Find hourly flight availability from Dulles Intl to St. Louis. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated March 21, 2025.

What is the cheapest day to fly from Washington, D.C. Dulles Intl Airport to St. Louis?

Use this chart to determine the cheapest time to fly round-trip from Dulles Intl to St. Louis. Price data was last updated on March 16, 2025.

Weekly flight availability from Washington, D.C. Dulles Intl Airport to St. Louis

Rainfall in St. Louis by month

Plan your trip to St. Louis by taking into account the average rainfall totals by month.

Temperature in St. Louis by month

Plan your trip to St. Louis by taking into account the average temperature totals by month.

Reviews of airlines servicing St. Louis

Read reviews from past customers who have flown Southwest, Delta and United Airlines from Washington, D.C. to St. Louis. In addition to providing an overall rating, users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.

Related info for your journey

Find useful and relevant information for your journey from Dulles Intl to St. Louis. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

What airport do you fly into for flights to St. Louis from Washington, D.C. Dulles Intl?

What are the cheapest airlines flying from Washington, D.C. Dulles Intl Airport to St. Louis round-trip?

What are the cheapest airlines to fly from Washington, D.C. Dulles Intl Airport to St. Louis one-way?

What are the most reliable airlines from Washington, D.C. Dulles Intl Airport to St. Louis?

What are the cheapest flights from Washington, D.C. Dulles Intl Airport to St. Louis?

Can I find deals for flights from Dulles Intl to St. Louis that include hotel bookings?

How can I find direct flights from Dulles Intl to St. Louis?

Can I find deals for business class flights from Dulles Intl to St. Louis?

What is the cheapest month to book a flight from Washington, D.C. Dulles Intl Airport to St. Louis?

Traveling to a place near Washington, D.C. Dulles Intl Airport?

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Alternative routes for Dulles Intl to St. Louis

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Top 3 airlines flying from Dulles Intl to St. Louis

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Cheapest flights from Dulles Intl to St. Louis
Explore the most affordable flight options available from Dulles Intl to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on March 21, 2025.