₩636,100 Cheap United flights Seattle (SEA) to London (LON)

View ₩636,100 flight on Wed, Apr 22, 2026Opens in a new window

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₩636,100 Cheap United flights Seattle (SEA) to London (LON)

Prices were available within the past 7 days and start at ₩636,100 for one-way flights and ₩941,100 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

United
Thu, Mar 19 - Wed, Mar 25
SEA
Seattle
LHR
London
₩941,100 Roundtrip, found 5 days ago
₩941,100
Roundtrip
found 5 days ago
Select United flight, departing Thu, Mar 19 from Seattle to London, returning Wed, Mar 25, priced at ₩941,100 found 5 days ago
United
Thu, Mar 19 - Wed, Mar 25
SEA
Seattle
LHR
London
₩953,100 Roundtrip, found 5 days ago
₩953,100
Roundtrip
found 5 days ago
Select United flight, departing Thu, Mar 19 from Seattle to London, returning Wed, Mar 25, priced at ₩953,100 found 5 days ago
United
Mon, Mar 30 - Wed, Apr 8
SEA
Seattle
LHR
London
₩986,400 Roundtrip, found 4 days ago
₩986,400
Roundtrip
found 4 days ago
Select United flight, departing Mon, Mar 30 from Seattle to London, returning Wed, Apr 8, priced at ₩986,400 found 4 days ago
United
Thu, Mar 19 - Wed, Mar 25
SEA
Seattle
LHR
London
₩1,085,400 Roundtrip, found 5 days ago
₩1,085,400
Roundtrip
found 5 days ago
Select United flight, departing Thu, Mar 19 from Seattle to London, returning Wed, Mar 25, priced at ₩1,085,400 found 5 days ago

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

October is typically the cheapest month to fly

From ₩698,579 - ₩1,312,075 per traveler.

Travel information

Origin airport
Seattle - Tacoma Intl.
Destination airport
Heathrow
Distance
7657 km
*Available to Expedia members.