$191 Find cheap flights from London, Ontario to Seattle

In the last 3 days, the lowest price for a flight from London, Ontario to Seattle was $191 for a one-way ticket and $373 for a round-trip.

A passport is required to fly from London to Seattle.

When flying out of London you will be using London. You will be landing at Seattle, also known as Seattle/Tacoma Intl.

We unfortunately don’t have that data for this specific route.

Star Alliance, and SkyTeam are the airline alliances operating flights between London and Seattle, with Star Alliance being the most commonly used for this route.

KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from London to Seattle.

KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Seattle from London is likely to change within 7 days, so travelers know whether to wait or book now.

Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to Seattle with an airline and back to London with another airline. Booking your flights between London and SEA can sometimes prove cheaper using this method.

Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to Seattle from London up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.