Find Cheap Flights from Lambert-St Louis to Washington Dulles Intl (STL - IAD)

Search hundreds of travel sites at once for deals on flights to Washington Dulles Intl

Sat 1/20
Sat 1/27
Any month
Compare vs. KAYAK |

Good to Know

Low Season:
August
Best time to beat the crowds
1%
expected price decrease
High Season:
February
Most popular time to fly
1%
expected price increase
Average Price:
$336
(avg. price over the last 2 weeks)
Good Deal:
$232
or less (round trip)

When to Book Flights from Lambert-St Louis to Washington Dulles Intl

Average price per month
Flight prices as travel date approaches
-1 day
-2 days

Top tips for Finding a Cheap Flight

Looking for a cheap flight? 25% of our users found flights on this route for $232 or less.
The cheapest flight from Lambert-St Louis to Washington Dulles Intl was found 50 days before departure, on average.
Book at least 2 weeks before departure in order to get a below-average price.
High season is considered to be January, February and March. The cheapest month to fly is August.
On average*, there is no price difference when choosing to fly in the morning or the evening on this flight route.
*Average of the lowest prices shown in KAYAK’s search results for departures within the next 30 days

FAQs for Booking Lambert-St Louis to Washington Dulles Intl Flights

How long does a flight from Lambert-St Louis to Washington Dulles Intl take?
An average nonstop flight takes 1h 59m, covering a distance of 695 miles.
How many flights are there between Lambert-St Louis and Washington Dulles Intl?
There are 162 (nonstop) flights between Lambert-St Louis and Washington Dulles Intl per week, averaging 23 per day.
Which airlines provide the cheapest flights from Lambert-St Louis to Washington Dulles Intl?
In the past 3 days, the cheapest round-trip tickets were found on United ($207), Delta ($224) and American Airlines ($259).
Do I need a passport to fly between Lambert-St Louis and Washington Dulles Intl?
No.
Which airlines fly most frequently between Lambert-St Louis and Washington Dulles Intl?
United (7 times daily), South African (5 times daily), SAS (2 times daily) are the most frequent flyers on this route.
What’s the cheapest day of the week to fly Lambert-St Louis to Washington Dulles Intl?
For Lambert-St Louis to Washington Dulles Intl, Monday is the cheapest day to fly on average and Monday is the most expensive. Flying from Washington Dulles Intl back to Lambert-St Louis, the best deals are generally found on Wednesday, with Monday being the most expensive.

Book cheap flights from Lambert-St Louis to Washington Dulles Intl (round-trip)

Airports
Origin
St. Louis
$207
only
$207
Destination
Washington
$207
only
$207
Mon, Feb 12
STL
IAD
2h 00m
Sat, Feb 17
IAD
STL
2h 29m
Trip: 6 days
7.3GoodShow reviews
Overall 7.3 Good
Based on 22 reviews
Overall
7.2
Boarding
7.4
Comfort
6.9
Crew
7.7
Entertainment
6.5
Food
6.4
STL
IAD
Good 6.0

Fast

Small plane

STL
IAD
Excellent 8.0

Gate agent was great.... Have me an edit row seat. But my 90 minute flight from St Louis, led to a 40 minute wait for my bag

STL
IAD
Mediocre 2.0

Our flight was delayed. We did not make the connecting flight. They would not provide us another flight same day or money back or money for the rental that we required.

STL
IAD
Good 6.0

Luggage compartment too small even for a rolling laptop bag

PVG
ORD
Okay 4.6

Entertainment, and leg space.

Full plane, long wait to use lavatory. Crew was good, but should have upped their game under the circumstances, especially with regards to keeping the lavatory clean. The noodles for breakfast turned out to be porridge, and went straight to the waste basket.

Thu, May 3
STL
IAD
4h 27m
Mon, May 7
IAD
STL
5h 03m
Trip: 5 days
7.8GoodShow reviews
Overall 7.8 Good
Based on 15315 reviews
Overall
8.0
Boarding
8.1
Comfort
7.7
Crew
8.4
Entertainment
7.5
Food
7.3
DTW
ATL
Excellent 8.0

I love Delta, especially their newer planes that have screens in the backs of headrests and free movies.

Leg room is never enough. I'm 6'1".

CMH
ATL
Okay 5.0

As poltronas estavam OK.

No voo MEX-GRU o Sistema de Entretenimento nao funcionou por quase 3hs. A refeicao foi muito fraca, tamto no jantar quanto no café da manhã. Onde ja se viu comer feijão preto com onelete no cafe da manhã??? Deveriam pensar no tipo de passageiro q estao atendendo.

BOS
AUS
Good 6.0

Delayed so I was not home until middle of the night.

ATL
BWI
Okay 4.6

Snacks & beverages on a 1 hour flight. Very nice crew

Older plane, no entertainment

MEX
ATL
Good 7.0

Beautiful plane, great entertainment system, two bathrooms for economy class, decent food

Wed, Apr 4
STL
IAD
5h 00m
Sun, Apr 8
IAD
STL
4h 39m
Trip: 5 days
7.2GoodShow reviews
Overall 7.2 Good
Based on 27334 reviews
Overall
7.3
Boarding
7.5
Comfort
7.1
Crew
7.8
Entertainment
6.7
Food
6.6
TPA
DFW
Good 6.3

Decent boarding group, same snacks, same flight attendants (who were very nice)

My only gripe is that paying for an assigned seat is only allowed 48 hours before takeoff and costs at least $30, twice what Spirit charges to allow you to select a seat during booking, so it is worse. No one watched us to ensure that we didn’t use the overhead bins (a stipulation of the fare) but we did comply anyway. We chose to take our chances and were assigned seats at the gate 16 rows apart and both in the middle seat.

BNA
ORD
Excellent 8.0

Short flight

The gate attendant did not wish me a good flight by name even though she wishes other passengers a good flight by name. I was disappointed with being singled out like that.

DFW
PHL
Mediocre 3.0

They separated my bags, so I had to wait in Philadelphia for my bag to arrive on next flight 2 1/2 hours latter. Not happy after flying from Sydney.

SLC
CLT
Okay 4.0

Flight attendants

The flight got delayed from salt lake and we had to spend a day in Charlotte before another flight came

DFW
SAT
Okay 5.6

The flight was so short we did not even get a snack, only an offer of a bottle of water; this was simply due to to short length of the flight. Basic economy had my wife and I 16 rows apart each in a middle seat. I was in the very last seat on the plane. Flight attendants were attentive and surprisingly very nice, legroom is non-existent (same as every flight in plain coach).

High cost to prebook seats was twice what Spirit or Frontier would charge

Tue, Mar 20
STL
IAD
2h 00m
Wed, Mar 21
IAD
STL
2h 20m
Trip: 2 days
7.3GoodShow reviews
Overall 7.3 Good
Based on 22 reviews
Overall
7.2
Boarding
7.4
Comfort
6.9
Crew
7.7
Entertainment
6.5
Food
6.4
STL
IAD
Excellent 8.0

Gate agent was great.... Have me an edit row seat. But my 90 minute flight from St Louis, led to a 40 minute wait for my bag

IAD
AMS
Mediocre 2.0

I didn't go. It was $400 just to change my name on my ticket from my maiden name to my married name. I am so disappointed and will never use Kayak again!!!

PVG
ORD
Okay 4.6

Entertainment, and leg space.

Full plane, long wait to use lavatory. Crew was good, but should have upped their game under the circumstances, especially with regards to keeping the lavatory clean. The noodles for breakfast turned out to be porridge, and went straight to the waste basket.

STL
IAD
Excellent 10.0

My wife was happy

Fixing my own supper

ORD
IND
Okay 4.6

Crew was very kind and apologetic for delay.

Delayed 2 hours and forced to deboard when I can drive in 3 hours.

Tue, Mar 27
STL
IAD
2h 00m
Mon, Apr 2
IAD
STL
2h 20m
Trip: 7 days
7.3GoodShow reviews
Overall 7.3 Good
Based on 22 reviews
Overall
7.2
Boarding
7.4
Comfort
6.9
Crew
7.7
Entertainment
6.5
Food
6.4
STL
IAD
Mediocre 2.0

Our flight was delayed. We did not make the connecting flight. They would not provide us another flight same day or money back or money for the rental that we required.

STL
IAD
Good 6.0

Departed close to on-time. And as a pilot myself any landing you walk away from is a good landing.

Boarding nearly last there was no room in the overhead compartments. This aircraft is tiny and with my small bag on the floor my feet rested on top of my bag making it cramped.

STL
IAD
Good 6.0

First flight went great.

PVG
ORD
Okay 4.6

Entertainment, and leg space.

Full plane, long wait to use lavatory. Crew was good, but should have upped their game under the circumstances, especially with regards to keeping the lavatory clean. The noodles for breakfast turned out to be porridge, and went straight to the waste basket.

STL
IAD
Good 6.6

The crew on the plane was nice and helpful.

I understand pretzels for the most part are allergy friendly however I have a gluten intolerance so I couldn’t have them and i couldn’t download the United app because there wasn’t WiFi available anywhere in the terminal and there weren’t any charging stations.

Sat, May 5
STL
IAD
2h 00m
Tue, May 8
IAD
STL
2h 12m
Trip: 4 days
7.3GoodShow reviews
Overall 7.3 Good
Based on 22 reviews
Overall
7.2
Boarding
7.4
Comfort
6.9
Crew
7.7
Entertainment
6.5
Food
6.4
STL
IAD
Good 6.0

Departed close to on-time. And as a pilot myself any landing you walk away from is a good landing.

Boarding nearly last there was no room in the overhead compartments. This aircraft is tiny and with my small bag on the floor my feet rested on top of my bag making it cramped.

STL
IAD
Good 6.0

Luggage compartment too small even for a rolling laptop bag

PVG
ORD
Okay 4.6

Entertainment, and leg space.

Full plane, long wait to use lavatory. Crew was good, but should have upped their game under the circumstances, especially with regards to keeping the lavatory clean. The noodles for breakfast turned out to be porridge, and went straight to the waste basket.

ORD
YUL
Mediocre 2.0

the comped hotel

Improper handling of situation. There was flight scheduled later, but CS agent kept jerking us around. By the time I reached the United counter, the next flight was full. My total flight time was 36 hours. I still can’t believe that the pilot was missing. Worse yet, the agent at the gate could have made things much easier instead of telling everyone that a pilot was on his way to the airport.

STL
IAD
Good 6.6

The crew on the plane was nice and helpful.

I understand pretzels for the most part are allergy friendly however I have a gluten intolerance so I couldn’t have them and i couldn’t download the United app because there wasn’t WiFi available anywhere in the terminal and there weren’t any charging stations.

Mon, Feb 19
STL
IAD
5h 17m
Tue, Feb 20
IAD
STL
2h 20m
Trip: 2 days
7.3GoodShow reviews
Overall 7.3 Good
Based on 22 reviews
Overall
7.2
Boarding
7.4
Comfort
6.9
Crew
7.7
Entertainment
6.5
Food
6.4
PVG
ORD
Okay 4.6

Entertainment, and leg space.

Full plane, long wait to use lavatory. Crew was good, but should have upped their game under the circumstances, especially with regards to keeping the lavatory clean. The noodles for breakfast turned out to be porridge, and went straight to the waste basket.

STL
IAD
Good 6.0

Luggage compartment too small even for a rolling laptop bag

IAD
AMS
Mediocre 2.0

I didn't go. It was $400 just to change my name on my ticket from my maiden name to my married name. I am so disappointed and will never use Kayak again!!!

ORD
IND
Okay 4.6

Crew was very kind and apologetic for delay.

Delayed 2 hours and forced to deboard when I can drive in 3 hours.

STL
IAD
Good 6.0

Departed close to on-time. And as a pilot myself any landing you walk away from is a good landing.

Boarding nearly last there was no room in the overhead compartments. This aircraft is tiny and with my small bag on the floor my feet rested on top of my bag making it cramped.

Mon, Jan 22
STL
IAD
1h 59m
Wed, Jan 24
IAD
STL
4h 35m
Trip: 3 days
Overall 0.0 Poor
Based on 0 reviews
Wed, Jun 27
STL
IAD
2h 00m
Tue, Jul 3
IAD
STL
2h 23m
Trip: 7 days
7.3GoodShow reviews
Overall 7.3 Good
Based on 22 reviews
Overall
7.2
Boarding
7.4
Comfort
6.9
Crew
7.7
Entertainment
6.5
Food
6.4
STL
IAD
Mediocre 2.0

Our flight was delayed. We did not make the connecting flight. They would not provide us another flight same day or money back or money for the rental that we required.

STL
IAD
Good 6.6

The crew on the plane was nice and helpful.

I understand pretzels for the most part are allergy friendly however I have a gluten intolerance so I couldn’t have them and i couldn’t download the United app because there wasn’t WiFi available anywhere in the terminal and there weren’t any charging stations.

ORD
IND
Okay 4.6

Crew was very kind and apologetic for delay.

Delayed 2 hours and forced to deboard when I can drive in 3 hours.

STL
IAD
Good 6.0

First flight went great.

STL
IAD
Good 6.0

Departed close to on-time. And as a pilot myself any landing you walk away from is a good landing.

Boarding nearly last there was no room in the overhead compartments. This aircraft is tiny and with my small bag on the floor my feet rested on top of my bag making it cramped.

Mon, Jan 22
STL
IAD
5h 16m
Fri, Feb 9
IAD
STL
4h 38m
Trip: 19 days
7.2GoodShow reviews
Overall 7.2 Good
Based on 27334 reviews
Overall
7.3
Boarding
7.5
Comfort
7.1
Crew
7.8
Entertainment
6.7
Food
6.6
MAD
JFK
Good 6.0

Films, TV screens did not work

DFW
SAT
Okay 5.6

The flight was so short we did not even get a snack, only an offer of a bottle of water; this was simply due to to short length of the flight. Basic economy had my wife and I 16 rows apart each in a middle seat. I was in the very last seat on the plane. Flight attendants were attentive and surprisingly very nice, legroom is non-existent (same as every flight in plain coach).

High cost to prebook seats was twice what Spirit or Frontier would charge

MAD
PHL
Good 7.0

Flight was not full.

Luggage was very late and arrived at the wrong carousel.

ORD
DFW
Excellent 8.0

Very timely, didn't take forever getting off the ground

As a first time traveler, it would have been nice to have a little help with navigating the airport once I arrived.

DFW
PHL
Mediocre 3.0

They separated my bags, so I had to wait in Philadelphia for my bag to arrive on next flight 2 1/2 hours latter. Not happy after flying from Sydney.

Sun, Mar 25
STL
IAD
5h 19m
Thu, Mar 29
IAD
STL
2h 29m
Trip: 5 days
7.3GoodShow reviews
Overall 7.3 Good
Based on 22 reviews
Overall
7.2
Boarding
7.4
Comfort
6.9
Crew
7.7
Entertainment
6.5
Food
6.4
STL
IAD
Excellent 10.0

My wife was happy

Fixing my own supper

ORD
YUL
Mediocre 2.0

the comped hotel

Improper handling of situation. There was flight scheduled later, but CS agent kept jerking us around. By the time I reached the United counter, the next flight was full. My total flight time was 36 hours. I still can’t believe that the pilot was missing. Worse yet, the agent at the gate could have made things much easier instead of telling everyone that a pilot was on his way to the airport.

STL
IAD
Mediocre 2.0

Our flight was delayed. We did not make the connecting flight. They would not provide us another flight same day or money back or money for the rental that we required.

STL
IAD
Good 6.0

Departed close to on-time. And as a pilot myself any landing you walk away from is a good landing.

Boarding nearly last there was no room in the overhead compartments. This aircraft is tiny and with my small bag on the floor my feet rested on top of my bag making it cramped.

STL
IAD
Good 6.0

First flight went great.

Show more results

Lambert-St Louis to Washington Dulles Intl Flight Information

Avg. Flight Duration 2h 10m
Flights Arrive in Washington Dulles Intl
Flights Depart from Lambert-St Louis
Flight Price $207
Distance 695 miles
Airlines United, Delta, American Airlines
*
Prices are per person and are for e–tickets and include all taxes & fees in USD.

We attempt to get accurate prices, however, prices are not guaranteed.

Here's why:

We’re not the seller.
At KAYAK we don’t set the prices, so it’s not possible for us to guarantee what other companies are selling.

We compile tonnes of data for you
Our service lets you quickly and easily compare results from hundreds of travel sites at once. In this sense, KAYAK is a search engine and we can't guarantee prices we find.

Why aren’t prices accurate 100% of the time?
Prices on airline seats, hotel rooms and car rentals can change frequently. Several people may also be trying to buy the same travel option simultaneously. As a result, you may find, on occasion, that certain prices are no longer available.

If you have more questions or if you have a bad price to report to us,
please send us an and someone from our team will get back to you promptly.

^
The fares displayed include all taxes and fees for economy class travel and were found by the provider in the last 72 hours. Seats are limited and may not be available on all flights and days. Fares are subject to change and may not be available on all flights or dates of travel. Some carriers charge additional fees for extra checked bags. Please check the carriers' sites.