Cheap Flights from Washington Dulles to London

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Flight deals from Washington Dulles to London

Looking for a cheap last-minute deal or the best return flight from Washington Dulles to London? Find the lowest prices on one-way and return tickets right here.

Find the cheapest month to fly from Washington Dulles to London

We’re always keeping an eye on fares, so you can find the best one in seconds. It looks like Washington Dulles to London flights are currently cheapest in May.

Direct flights from Washington Dulles to London

Alternative Washington Dulles to London routes

Looking for the cheapest, fastest or easiest route from Washington Dulles to London? You could fly into the following airports instead.

Washington D.C. to London: Flight information

The things to know before you go.
Cheapest flight found432 €
Cheapest month to flyMay
Average flight time7 hrs, 23 mins
Most popular airlineAmerican Airlines
Average flights per week229

Finding cheap flights from Washington Dulles to London: Frequently asked questions

There are 6 airports in London: London City, London Heathrow, London Gatwick, London Luton, London Stansted, and London Southend.
The best price we found for a return flight from Washington Dulles to London is 432 €. This is an estimate based on information collected from different airlines and travel providers over the last 4 days and is subject to change and availability.
7 hours and 23 minutes is the average flight time from Washington Dulles to London.
American Airlines, British Airways and KLM fly direct from Washington Dulles to London.
As of March 2025, there are 229 flights per week flying from Washington Dulles to London.
The cheapest month to fly from Washington Dulles to London is usually March 2025.
If you're flying from Washington Dulles Airport, the cheapest airport near London is London Heathrow – which is 22.9 km away from the centre of London. We've found flights into this airport from 432 €.
After crunching the numbers on our flight calendar, we found that it's currently cheapest to fly from Washington Dulles Airport to London on Saturday, 3 May 2025.
Yes – the average flight time is 7 hours and 23 minutes.
We show every price from over 1,200 airlines and travel agents, comparing them all so you don’t have to. If you know you want to fly to London but you’re not ready to book, set up a Price Alert. We’ll track prices for you, and let you know when they rise or fall.
We crunched all the numbers in our flight calendar and it looks like the cheapest time to book a flight to London is around 40 days in advance, so don’t leave your flight to the last minute.
In March, the average temperature is usually around 6°C. August is typically the warmest month in London, when it usually averages around 22°C. You can expect the least rain in March. The coldest month is January, with temperatures averaging 1°C. The rainiest month is October.
Currently, Austrian Airlines and Iberia offer the cheapest flight tickets to London.

Travelling from Washington Dulles International Airport (IAD) to London: what you need to know

  • The average time for a direct flight from Washington Dulles International Airport to London is 8 hours 20 minutes.

  • The timezone in London is UTC+0. The city is 4 hours ahead of Washington DC, where Washington Dulles International Airport is located.

  • With 56 weekly flights between the two airports, Washington Dulles International Airport (IAD) to London Heathrow Airport (LHR) is the most popular route. United operates the earliest flight at 08:30. If you'd like to make the most of your day before flying, the last flight from IAD to LHR is with United at 23:35.

  • Leave enough time to get on your flight from IAD to London. As a rule of thumb, arrive at least two hours before international departures and an hour ahead for domestic flights.

  • Getting away during a peak time like July? Popular seasons (like summer, Christmas/New Year and spring break) can easily add another hour at security. Be extra cautious and arrive up to four hours before international flights and two hours before domestic departures.

  • You can book a nonstop flight from Washington Dulles International Airport to London that lands at London Heathrow Airport (LHR).

  • You'll find a variety of airlines offering direct flights from Washington Dulles International Airport to London, such as:

  • A stopover is the perfect opportunity to take a break from travelling — and possibly even explore a different city. When browsing flights from IAD to London, uncheck the 'Direct flights only' box to see where you can stop along the way. Popular options include:

    • Dublin Airport (DUB)

    • Newark Liberty International Airport (EWR)

    • Logan International Airport (BOS)

  • If you hold a passport from United States and want to travel to United Kingdom for tourism purposes, you won't need a visa. However, entry and visa requirements may vary based on the length of your trip and can be subject to change. For the most up-to-date information, contact your destination's nearest consulate or embassy before booking a cheap ticket from Washington Dulles International Airport to London.

  • Located around 56 kilometres from the centre of Washington DC, IAD can be reached in approximately 51 minutes by car, depending on traffic. The same journey by public transport is roughly 3 hours and 26 minutes.

  • Need a convenient hotel near IAD? If you're boarding an early flight from Washington Dulles International Airport to London, these accommodation options will have you moments from check-in:

How to find the cheapest flights from Washington Dulles International Airport (IAD) to London

  • 176 € is the lowest price for a one-way ticket from Washington Dulles International Airport to London. A return flight starts from 432 €. These prices may change depending on demand and availability.

  • Lock in cheap tickets from IAD to London by booking 11 months ahead. Based on our research, that's the sweet spot for finding the biggest deals.

  • Schedule your trip for July. That's the cheapest month for tickets from Washington Dulles International Airport to London. If you have flexibility with your dates, use the 'Whole month' tool to find the lowest price across every month.

  • Create a Price Alert for cheap tickets from IAD to London. You don't need to look every day to see if prices have dropped. We'll let you know as soon as there's a change in price.

  • Tailor your flights with filters. Pick your ideal arrival and departure times, total journey duration and airlines. You can also sort results by 'Best,' 'Cheapest' or 'Fastest' flights from Washington Dulles International Airport to London.

Airports in London

London Heathrow Airport (LHR)

  • London Heathrow Airport (LHR) to central London is approximately 31 kilometres. It takes around 57 minutes to get to the centre driving.

  • Getting there by public transport takes around 1 hour and 1 minute.

  • If you have a late flight from Washington Dulles International Airport to London, few things beat the convenience of staying near the terminal. Collect your bags from the carousel and then be showered and resting not long after at one of these accommodation options near LHR:

London Gatwick Airport (LGW)

  • Central London is approximately 80 kilometres from London Gatwick Airport (LGW). As soon as your flight from Washington Dulles International Airport to London has landed and you've made your way out of the airport, the drive should take about 1 hour and 19 minutes.

  • Travelling by public transport will take around 1 hour and 26 minutes.

  • Hang the 'Do not disturb' sign on your door and unwind at a hotel near LGW. Here are a few options where you can tuck yourself in after your flight from IAD to London:

Best time to go to London

  • July is the most popular month for flights from Washington Dulles International Airport to London. To skip the crowds, visit London in February when things are quieter.

  • When booking your flight from Washington Dulles International Airport to London, think about the kind of weather you enjoy. July is the warmest month in London, with temperatures ranging from 11ºC to 26ºC.

  • Look for cheap flights from IAD to London in January if you want to travel in cooler conditions. Temperatures are at their lowest then, ranging between 0ºC and 9ºC on average.

More about London

  • When it comes to looking for somewhere to rest your head, you'll find the most popular stays in London right here. Check out these options once you've locked in your flight from Washington Dulles International Airport to London:

  • There are so many things to explore in this city it can be hard to know where to start. Big Ben, The British Museum and Buckingham Palace are leading attractions which should feature on any well-planned London itinerary.

Complete your London trip with a car rental

  • Select one of our car rentals in London and see the sights at your leisure. Easily compare options in one place to find your ideal ride once you've booked your hotel and cheap flights from Washington Dulles International Airport to London.

Prices shown on this page are estimated lowest prices only. Found in the last 45 days.