£251 Find Cheap Flights from Seattle to London Heathrow Airport – Compare and Save

These are the earliest and latest flight times available from Seattle to London Heathrow Airport:

• Earliest: departs at 13:30 and lands at 23:06
• Latest: departs at 21:50 and lands at 07:26.

The flight takes about 9h 36m.

Three cabin classes are available on flights from Seattle to London Heathrow Airport:

• Economy class
• Premium Economy Class
• Business Class

A direct flight from Seattle to London Heathrow Airport takes 9h 36m, covering 4,783 miles.

Yes, a valid passport is required for this international route. Many destinations require at least six months of validity beyond your travel dates. Check your passport expiry well before booking.

Return flights from Seattle to London Heathrow Airport range from £552 to £859, with an average of £690 over the past 12 months. Anything below £552 counts as a good deal.

Last-minute fares on this route (booked within two weeks of departure) run 21% above the £690 route average. Book 19 weeks before departure for the lowest fares.

On this route, stopover flights are cheaper than direct options on average. Stopover fares average £479 return via Montreal Pierre Elliott Trudeau Intl (YUL), compared with £713 for direct.

Virgin Atlantic is slightly above the route average for timely arrivals, while Delta has a lower on-time arrival rate. On-time arrival rates on Seattle to London Heathrow Airport flights are:

• Virgin Atlantic: 96% on time
• Delta: 89% on time
• Alaska Airlines: 82% on time

On average, flights on this route are punctual 86% of the time.

There is no standard. Checked bag policies vary by airline on this route. Most carriers charge £42–£75 for the first checked bag in Economy. Premium fares and elite status bookings typically include a free checked bag.

The Boeing 787-10 Dreamliner family is used most often on this route, operated mainly by British Airways and Finnair. Other aircraft seen on the route include Airbus A330-900neo variants.

Evening is the busiest departure period on Seattle to London Heathrow Airport flights, with 66% leaving in that window. Afternoon departures account for 33%, Morning flights for 1%, and Night flights for 0%.

Four airlines offer in-flight Wi-Fi on Seattle to London Heathrow Airport flights:

• Virgin Atlantic
• Delta
• Air France
• KLM

Pricing varies by airline and fare class. Some plans are included with the ticket or loyalty programme, while others are paid add-ons priced by flight length.

One-way fares from Seattle to London Heathrow Airport are currently lower than usual. Average one-way flight prices are about £274, which is 29% below the typical average for this route.

London Heathrow Airport (LHR) hosts 5 major car hire companies, with daily rates starting from around £5 for economy cars. Top options include:

• GREEN MOTION
• DRIVALIA
• Europcar
• Alamo
• Hertz

Flights from Seattle to London Heathrow Airport usually depart from Seattle/Tacoma Intl (SEA) and arrive at London Heathrow (LHR).

Night flights have the fewest delays on this route, while evening departures tend to have the most.

A flight is considered delayed when it departs 15 minutes or more after its scheduled time. This is the standard used by the US Department of Transportation and most airline industry reporting. On the Seattle to London Heathrow Airport route, 14% of flights were delayed in the past three months, with delays averaging 2h 12m.

One-stop flights from Seattle to London Heathrow Airport most commonly connect through:

• Reykjavik Keflavik Intl (KEF) – 68% of one-stop connections
• Dublin (DUB) – 13% of one-stop connections
• Kastrup Copenhagen (CPH) – 8% of one-stop connections
• Vancouver Intl (YVR) – 4% of one-stop connections

Yes. Flexible dates can save you up to 15% on flights from Seattle to London Heathrow Airport. Monday is the cheapest departure day at £646 return on average, while Friday is the most expensive at £754, a difference of £108.

KAYAK's flexible dates feature shows options up to three days before and after your selected dates, making it easier to compare nearby fares.

4 airlines operate flights between Seattle and London Heathrow Airport. The airlines offering direct flights on this route include:

• British Airways
• Alaska Airlines
• Delta
• Virgin Atlantic

Flying via Amsterdam Schiphol (AMS) gives the shortest average 1-stop total travel time of 12h 54m, compared to 13h 10m via Dublin (DUB) and 13h 34m via Denver Intl (DEN).

London Heathrow Airport is 8 hours ahead of Seattle (British Time vs Pacific Time). Plan for the time shift when scheduling connections or first-day activities.

Some of the most popular sights in London Heathrow Airport are Hyde Park, Tower Bridge, and Royal Albert Hall. These are among the most viewed places in London Heathrow Airport on KAYAK.

Among airlines operating Seattle to London Heathrow Airport flights:

• Alaska Airlines: offers free seat selection
• British Airways: offers extra legroom; offers free seat selection
• Virgin Atlantic: offers extra legroom; offers free seat selection
• Delta: offers extra legroom; offers free seat selection
• Air France: offers extra legroom; offers free seat selection

Extra legroom and free seat selection availability depends on fare class and route.

Here are some options for this route, based on selected ticket types and cabin classes:

• Alaska Airlines: a cabin bag and a checked bag in Economy class
• British Airways: a cabin bag and a checked bag in Economy class
• Virgin Atlantic: a cabin bag and a checked bag in Economy class

Baggage allowance can vary by ticket type, cabin class, route, and airline, so always check the fare details before booking.