Expect long security queues at IAD, especially in the afternoon and evening. Arrive early to navigate the check-in and security process smoothly.
Most accurate provider | FlightHub 3 stars |
---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $539 (Scandinavian Airlines) |
One-way from | $177 (Trip.com) |
Popular in | June |
Cheapest in | September |
Average price | $662 |
Good round-trip deal | $663 or less |
Good one-way deal | $380 or less |
Fly from
Fly to
Route
Depart
Return
Price
Washington, D.C.London
IAD - LGW
IADLGW
Washington, D.C. Dulles Intl
Sun 11/16
10:30 pm-9:50 am
1 stop30h 20m
London Gatwick
Mon 11/24
11:00 am-2:35 pm
2 stops32h 35m
Washington, D.C.London
IAD - STN
IADSTN
Washington, D.C. Dulles Intl
Sun 11/23
9:45 am-10:35 pm
3 stops31h 50m
London Stansted
Tue 12/2
7:30 am-8:59 pm
2 stops18h 29m
Washington, D.C.London
IAD - LGW
IADLGW
Washington, D.C. Dulles Intl
Fri 3/13
8:40 pm-10:55 am
1 stop10h 15m
London Gatwick
Tue 3/17
11:55 am-7:30 pm
1 stop11h 35m
Washington, D.C.London
IAD - STN
IADSTN
Washington, D.C. Dulles Intl
Mon 11/24
9:45 am-8:55 pm
2 stops30h 10m
London Stansted
Mon 12/1
1:55 pm-4:40 pm
2 stops31h 45m
Washington, D.C.London
IAD - LTN
IADLTN
Washington, D.C. Dulles Intl
Mon 12/8
7:40 pm-2:00 pm
1 stop13h 20m
London Luton
Mon 12/15
8:00 am-6:30 pm
1 stop15h 30m
Washington, D.C.London
IAD - STN
IADSTN
Washington, D.C. Dulles Intl
Sat 1/17
8:30 pm-1:05 pm
1 stop11h 35m
London Stansted
Sat 1/24
11:00 am-6:50 pm
1 stop12h 50m
Washington, D.C.London
IAD - LGW
IADLGW
Washington, D.C. Dulles Intl
Thu 1/29
5:30 pm-9:50 am
1 stop11h 20m
London Gatwick
Sun 2/1
9:05 am-9:00 pm
2 stops16h 55m
Washington, D.C.London
DCA - LGW
DCALGW
Washington, D.C. Reagan-National
Mon 11/24
10:16 am-9:00 am
1 stop17h 44m
London Gatwick
Wed 12/10
12:30 pm-1:49 pm
1 stop30h 19m
Washington, D.C.London
IAD - LHR
IADLHR
Washington, D.C. Dulles Intl
Wed 11/5
10:15 pm-10:50 am
Nonstop7h 35m
London Heathrow
Thu 11/13
6:35 am-8:05 pm
1 stop18h 30m
Washington, D.C.London
IAD - LHR
IADLHR
Washington, D.C. Dulles Intl
Sun 11/9
6:20 pm-6:40 am
Nonstop7h 20m
London Heathrow
Tue 11/18
6:35 am-3:35 pm
1 stop14h 00m
Provider | Price Accuracy | Trust Score* |
---|---|---|
Price Accuracy2 stars | Trust Score*3 stars | |
Price Accuracy3 stars | Trust Score*3 stars | |
Price Accuracy3 stars | Trust Score*3 stars | |
Price Accuracy3 stars | Trust Score*3 stars | |
Price Accuracy2 stars | Trust Score*2 stars | |
Price Accuracy3 stars | Trust Score*3 stars | |
Price Accuracy3 stars | Trust Score*3 stars | |
Price Accuracy3 stars | Trust Score*3 stars | |
Price Accuracy2 stars | Trust Score*2 stars | |
Price Accuracy3 stars | Trust Score*1 star |
The best time to book flights from Washington, D.C. to London is 47 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.
Currently, March is the cheapest month in which you can book a flight from Washington, D.C. to London (average of $31). Flying from Washington, D.C. to London in June is currently the most expensive (average of $748). 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.
A simple way to save on the total cost of your ticket is to fly from Washington, D.C. to London in the afternoon. If you’re flexible enough to do this you can expect to save up to 16% on your trip compared to booking a flight at noon.
Travelers seeking maximum savings on their Washington, D.C. to London flight should consider departing on Sunday afternoons when fares are most often at their lowest. Friday at noon flights should be avoided if possible as fares are typically the most expensive at this time.
The most flights from WAS to LON are scheduled on a Wednesday (26 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (21 on average).
Reykjavik (KEF) – chosen by Cheapflights users on 73% of 1-stop itineraries from Washington, D.C. to London on Cheapflights.
Dublin (DUB) is the most affordable 1-stop option, with an average round-trip price of $479.
Flights via Montreal (YUL) have the shortest average one-way travel time for 1-stop routes: 9h 20m.
Flights via Reykjavik (KEF) offer the fastest connection on this route, with an average layover time of 1h 23m.
Comfort
Boarding
Entertainment
Crew
Overall
Food
Reviews
Tim,Sep 2025
IAD - GSP
Comfort
Boarding
Entertainment
Crew
Overall
Food
Reviews
Tim,Sep 2025
IAD - GSP
Comfort
Boarding
Entertainment
Crew
Overall
Food
Reviews
Tim,Sep 2025
IAD - GSP
Comfort
Boarding
Entertainment
Crew
Overall
Food
Reviews
Tim,Sep 2025
IAD - GSP
Comfort
Boarding
Entertainment
Crew
Overall
Food
Reviews
Tim,Sep 2025
IAD - GSP
Comfort
Boarding
Entertainment
Crew
Overall
Food
Reviews
Tim,Sep 2025
IAD - GSP
Airline | Cheapest | Average | Flexibility | On-time |
---|---|---|---|---|
Cheapest$31 | Average$806 | FlexibilityNo cancel fee | On-time62% | |
Cheapest$369 | Average$487 | FlexibilityNo cancel fee | On-timeN/A | |
Cheapest$395 | Average$580 | FlexibilityNo cancel fee | On-timeN/A | |
Cheapest$397 | Average$859 | FlexibilityNo cancel fee | On-time76% | |
Cheapest$421 | Average$805 | FlexibilityNo cancel fee | On-timeN/A | |
Cheapest$424 | Average$596 | FlexibilityNo cancel fee | On-time77% | |
Cheapest$433 | Average$630 | FlexibilityNo cancel fee | On-time76% | |
Cheapest$497 | Average$851 | FlexibilityNo cancel fee | On-time72% | |
Cheapest$497 | Average$851 | FlexibilityNo cancel fee | On-time71% | |
Cheapest$506 | Average$860 | FlexibilityNo cancel fee | On-time69% |