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

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Sat 11/18
Sat 11/25
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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:
$335
(avg. price over the last 2 weeks)
Good Deal:
$231
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

When looking for a cheap flight, consider that 25% of our users selected a flight on this route for $231 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.
Morning departure is around 29% more expensive than an evening flight, on average*.
*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 221 (nonstop) flights between Lambert-St Louis and Washington Dulles Intl per week, averaging 31 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), Frontier ($320) and Delta ($320).
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 (11 times daily), South African (8 times daily), Brussels Airlines (3 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, Tuesday 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 Thursday, with Wednesday 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
Tue, Jan 23
STL
IAD
1h 59m
Sat, Jan 27
IAD
STL
2h 29m
Trip: 5 days
7.4GoodShow reviews
Overall 7.4 Good
Based on 19 reviews
Overall
7.2
Boarding
7.3
Comfort
6.9
Crew
7.7
Entertainment
6.5
Food
6.4
STL
IAD
Good 6.0

Luggage compartment too small even for a rolling laptop bag

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.

SJC
EWR
Mediocre 3.6

Arrived on time

Narrow seat

EWR
PBI
Okay 4.6

Arrived on time

Distance between gates

DEN
IAD
Okay 4.3

Staff was friendly

United has a system glitch and we were delayed. I got in around 1 am instead of 11 pm. I decide to order a glass of wine and since they don’t give receipts. I found out i was charged for 2 glasses instead of one. To top it off the co-worker i was traveling with didn’t get charged due to the inconvenience and delay. i travel a lot with United (higher status than him) and would have liked that offer (and not get charged one i didn’t order) being a mileage plus and credit card holder. I did go on line and ask for a credit and they did make it right and give me a credit.

Sun, Nov 19
STL
IAD
27h 04m
Tue, Nov 28
IAD
STL
10h 50m
Trip: 10 days
5.6OkayShow reviews
Overall 5.6 Okay
Based on 32923 reviews
Overall
5.9
Boarding
6.4
Comfort
5.4
Crew
6.8
Entertainment
4.5
Food
4.7
PVD
TPA
Excellent 9.3

Cheap, comfortable and friendly staff

Getting off the plane took forever on both legs.

LGA
MIA
Mediocre 3.6

Flight Very late , when departure already at night Uncomfortable seats $45 for a bag and I have drop it off myself after pay

DEN
SLC
Okay 5.6

Food, entertainment NA, didn’t use. Rest of flight uneventful, happy to say. Because this was so late due to previous leg of journey delayed, our planned transportation to hotel wa not available.

PBI
ISP
Mediocre 2.0

Was unable to make it

FSD
DEN
Okay 4.6

The scheduled plane had a mechanical problem so we deplaned for alternative plan. It took six long hours to get another plane in. Meantime passengers stood in line for hours to make other arrangements. It would have been appropriate for the airline to call in extra staff to help stranded passengers. We missed the scheduled connecting flight and a tour. We got in at 1:00 am, 12 hours later than planned. We had meetings next day and were very tired because we got in so late

Fri, Apr 6
STL
IAD
4h 09m
Sun, Apr 8
IAD
STL
4h 45m
Trip: 3 days
7.8GoodShow reviews
Overall 7.8 Good
Based on 13528 reviews
Overall
8.0
Boarding
8.1
Comfort
7.7
Crew
8.4
Entertainment
7.5
Food
7.3
LGA
CVG
Excellent 8.3

Plane was far too tight. Very uncomfortable for taller individuals.

DTW
EWR
Excellent 8.0

Boarding was quick. Staff and crew were friendly. Everything went well despite the 30 min delay we had on the runway. They gave us snacks and we ended up still arriving on time.

MOB
ATL
Good 6.0

Felt like I was sitting in my neighbors lap!

JFK
JAX
Good 7.6

Delta never used to be my first choice in airlines, but of my recent experience with them has been excellent. The people from the counter to the plane have been professional and courteous. This is why I will fly with them more frequently.

YUL
ATL
Good 6.0

Fligth were on time

My flight from Montreal to Atlanta was 2:30 min Left at 6:10 arrive at 8:30 roughly Tried twice to get to my connection earlier and get 9:30 instead of 12:09 fligth to Daytona Delta was not flexible to allow me to book saying i did not have 55 min in between fligth which i had than lear n it will cost $75.00 to change the fligth - What? Very disappointed of Delta - lost 3 hrs at the airport today

Mon, Feb 12
STL
IAD
1h 59m
Mon, Feb 19
IAD
STL
2h 12m
Trip: 8 days
7.4GoodShow reviews
Overall 7.4 Good
Based on 19 reviews
Overall
7.2
Boarding
7.3
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

HNL
LAX
Okay 5.6

Flight was delayed over 8 hours due to "mechanical issues." Went from a nice 757 to a 737 which was a little more cramped.

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.

LAX
ORD
Good 7.3

The crew was excellent

The seating space is to small

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.

Tue, Mar 20
STL
IAD
2h 08m
Sat, Mar 24
IAD
STL
2h 12m
Trip: 5 days
7.4GoodShow reviews
Overall 7.4 Good
Based on 19 reviews
Overall
7.2
Boarding
7.3
Comfort
6.9
Crew
7.7
Entertainment
6.5
Food
6.4
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.

DEN
IAD
Okay 4.3

Staff was friendly

United has a system glitch and we were delayed. I got in around 1 am instead of 11 pm. I decide to order a glass of wine and since they don’t give receipts. I found out i was charged for 2 glasses instead of one. To top it off the co-worker i was traveling with didn’t get charged due to the inconvenience and delay. i travel a lot with United (higher status than him) and would have liked that offer (and not get charged one i didn’t order) being a mileage plus and credit card holder. I did go on line and ask for a credit and they did make it right and give me a credit.

HNL
LAX
Okay 5.6

Flight was delayed over 8 hours due to "mechanical issues." Went from a nice 757 to a 737 which was a little more cramped.

STL
IAD
Excellent 10.0

My wife was happy

Fixing my own supper

STL
IAD
Good 6.0

First flight went great.

Mon, Dec 25
STL
IAD
2h 00m
Thu, Dec 28
IAD
STL
2h 24m
Trip: 4 days
7.4GoodShow reviews
Overall 7.4 Good
Based on 19 reviews
Overall
7.2
Boarding
7.3
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

LAX
ORD
Good 7.3

The crew was excellent

The seating space is to small

STL
IAD
Good 6.0

Fast

Small plane

STL
IAD
Good 6.0

Luggage compartment too small even for a rolling laptop bag

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

Thu, Mar 15
STL
IAD
2h 00m
Sun, Mar 18
IAD
STL
2h 12m
Trip: 4 days
7.4GoodShow reviews
Overall 7.4 Good
Based on 19 reviews
Overall
7.2
Boarding
7.3
Comfort
6.9
Crew
7.7
Entertainment
6.5
Food
6.4
EWR
PBI
Okay 4.6

Arrived on time

Distance between gates

LAX
ORD
Good 7.3

The crew was excellent

The seating space is to small

DEN
IAD
Okay 4.3

Staff was friendly

United has a system glitch and we were delayed. I got in around 1 am instead of 11 pm. I decide to order a glass of wine and since they don’t give receipts. I found out i was charged for 2 glasses instead of one. To top it off the co-worker i was traveling with didn’t get charged due to the inconvenience and delay. i travel a lot with United (higher status than him) and would have liked that offer (and not get charged one i didn’t order) being a mileage plus and credit card holder. I did go on line and ask for a credit and they did make it right and give me a credit.

STL
IAD
Good 6.0

Luggage compartment too small even for a rolling laptop bag

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.

Fri, May 4
STL
IAD
2h 08m
Sun, May 6
IAD
STL
2h 12m
Trip: 3 days
7.4GoodShow reviews
Overall 7.4 Good
Based on 19 reviews
Overall
7.2
Boarding
7.3
Comfort
6.9
Crew
7.7
Entertainment
6.5
Food
6.4
STL
IAD
Good 6.0

Luggage compartment too small even for a rolling laptop bag

LAX
ORD
Good 7.3

The crew was excellent

The seating space is to small

STL
IAD
Good 6.0

Fast

Small plane

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.

EWR
PBI
Okay 4.6

Arrived on time

Distance between gates

Mon, Nov 27
STL
IAD
1h 59m
Sat, Dec 2
IAD
STL
2h 22m
Trip: 6 days
7.4GoodShow reviews
Overall 7.4 Good
Based on 19 reviews
Overall
7.2
Boarding
7.3
Comfort
6.9
Crew
7.7
Entertainment
6.5
Food
6.4
STL
IAD
Good 6.0

Fast

Small plane

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.

EWR
PBI
Okay 4.6

Arrived on time

Distance between gates

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.

DEN
IAD
Okay 4.3

Staff was friendly

United has a system glitch and we were delayed. I got in around 1 am instead of 11 pm. I decide to order a glass of wine and since they don’t give receipts. I found out i was charged for 2 glasses instead of one. To top it off the co-worker i was traveling with didn’t get charged due to the inconvenience and delay. i travel a lot with United (higher status than him) and would have liked that offer (and not get charged one i didn’t order) being a mileage plus and credit card holder. I did go on line and ask for a credit and they did make it right and give me a credit.

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