Cheap Flights from London to Seattle Starting at $351

London is served by several distinct airports that cater to different traveler needs. Heathrow is the city’s primary international hub, typically handling long-haul and full-service carriers; it sits about 20 miles west of central London and can be reached by the Heathrow Express (15–25 minutes, premium fares), London Underground (50–60 minutes, lower fares) and taxis (40–70 minutes depending on traffic). Gatwick to the south often acts as a major alternative for both legacy and low-cost airlines, roughly 28 miles from central London with a Gatwick Express or regular trains taking 30–45 minutes; fares vary by operator. Stansted and Luton to the north are commonly used by budget carriers and package flights; journeys to central London usually take 40–60 minutes by express train or coach and can be more economical for price-sensitive travelers. London City Airport, close to Canary Wharf and the Docklands (about 8 miles east of the core), is usually favored by business travelers for its proximity and short transfer times—often 20–30 minutes by taxi or Docklands Light Railway—though it typically serves fewer long-haul routes. Pros across the network include wide route choices and frequent services; cons can include variable transfer times, congestion during peak periods and differing comfort levels depending on airport size and operator.

Seattle–Tacoma International Airport (SEA) is the region’s primary international hub, typically serving a mix of legacy carriers and several low-cost airlines on domestic and transpacific routes. Located about 14 miles south of downtown Seattle, travel times to the city center are commonly 20–35 minutes by Link light rail or 20–45 minutes by car depending on traffic; fares for public transit are usually in the low single digits, while taxi and rideshare fares can be moderate to high. SEA is generally convenient for connecting flights and offers extensive amenities, though it can be busy during peak hours; parking and peak-hour driving may be less comfortable for budget-conscious travellers.

In different months, ticket prices from London to Seattle vary: minimum — $415 (December 2025), maximum — $517 (November 2025). Typically, the flight costs $466–$517.

The route London — Seattle is served by many carriers — 4 in total, including British Airways, Ryanair, Westjet, and Vueling. This gives passengers wide opportunities: from finding the lowest fare (from $351) to selecting flights by schedule or service class. Our service aggregates data from multiple booking systems so you can compare offers in one place. This saves time and money: no need to check dozens of sites — just pick the right option and book online.