$375 Cheap American Airlines flights Seattle (SEA) to London (LHR)

View $375 flight on Sun, Feb 22, 2026Opens in a new window

$375 Cheap American Airlines flights Seattle (SEA) to London (LHR)

Prices were available within the past 7 days and start at $375 for one-way flights and $730 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

American Airlines
Sat, Apr 4 - Sat, Apr 18
SEA
Seattle
LHR
London
$730 Roundtrip, found 3 days ago
$730
Roundtrip
found 3 days ago
Select American Airlines flight, departing Sat, Apr 4 from Seattle to London, returning Sat, Apr 18, priced at $730 found 3 days ago

Find the cheapest month to fly from Seattle (SEA) to London (LHR)

October is typically the cheapest month to fly

From $477 - $843 per traveler.
Flights from Seattle (SEA) to London (LHR)
Origin airport
Seattle - Tacoma Intl.
Destination airport
Heathrow
Airlines serving
Aer Lingus, Air Canada, Air France, Alaska Airlines, Austrian Airlines, British Airways, Brussels Airlines, Delta, Finnair, Iberia, Icelandair, KLM, Lufthansa, United, Virgin Atlantic
Popular airline
Virgin Atlantic
Distance
7657 km
Average flight time
17 hours 35 mins