- Flight
- About 9 to 9.5 hours
- Departs
- SEA, Seattle
- Lands at
- Heathrow (LHR)
- Time difference
- London is 8 hours ahead
The flight from SEA to LHR
A nonstop flight from Seattle-Tacoma International Airport to Heathrow takes about 9 to 9.5 hours. London is 8 hours ahead of Seattle, so the clock does part of the work: as a guide, a flight that leaves at 6pm local time lands at about 11:30am London time the next day, and one that leaves at 10pm lands at about 3:30pm. These are typical times, not a timetable, and a fare with a stop takes longer.
Sea-Tac is about 14 miles south of downtown Seattle, and the Link light rail runs from the airport to the centre in about 40 minutes.
A taxi or rideshare takes 25 to 40 minutes depending on traffic, so leave slack if you are heading for an evening flight.
Landing at Heathrow
Allow an hour or more from touchdown to the kerb: passport control, baggage and the walk to the train. Hotel rooms are rarely ready before about two or three in the afternoon, so ask about early check in, or somewhere to leave your bags.
From Heathrow the Heathrow Express reaches Paddington in about 15 minutes and the Elizabeth line in about 30. The Piccadilly line crosses central London in 40 to 55 minutes, and a taxi takes 45 to 75 minutes depending on traffic.
Areas near where you land
The big figure is the straight line distance from Heathrow in miles, and nothing about travel time, which in London is always longer. Each page has the stations, the route from the airport and the measured rates.
Also close to where you land, with no profiles of their own but a guide to getting there and how outcall works: Feltham, Hayes, Hounslow, Southall.
When to get in touch
London runs 8 hours ahead of you. Messages sent between about 3am and 3pm your time land during London working hours, which is when replies actually come.
Before you book
Visitors from the United States who do not need a visa still need an electronic travel authorisation, or ETA, before they fly. It is a short online application, and it should be made through the official GOV.UK ETA service, not a site that charges extra to do it for you. The rules change, so check them before you book.
The full guide to flying to London from Seattle covers the entry rules and how to plan the first evening.
Airports with a similar flight time
See every US and Canadian airport
Common questions
How long is the flight from SEA to LHR?
A nonstop flight from Seattle-Tacoma International Airport to London Heathrow takes about 9 to 9.5 hours. Add the connection time if your fare has a stop, and allow for getting to and through the airport at both ends.
What time do flights from SEA land in London?
As a guide, a flight that leaves SEA at 6pm local time lands at about 11:30am London time the next day, and one that leaves at 10pm lands at about 3:30pm. London is 8 hours ahead of Seattle. Check your own ticket for the real times.
What is the time difference between Seattle and London?
London is 8 hours ahead. The United Kingdom and most other countries change their clocks on different dates, so for a few weeks each spring and autumn the gap shifts by an hour.
What time should I message from Seattle?
London runs 8 hours ahead of you. Messages sent between about 3am and 3pm your time land during London working hours, which is when replies actually come.
Which London airport do flights from SEA land at?
Most land at Heathrow, about fifteen miles west of central London and on the Piccadilly line and the Elizabeth line. Some services use Gatwick, to the south, so check the airport on your ticket before you book a hotel.
Do I need an ETA to fly from SEA to London?
Most visitors from the United States who do not need a visa need an electronic travel authorisation, or ETA, before they fly. Apply through the official GOV.UK service only, and check the current rules before you book, because they change.