Cheap flights from Seattle to South London

View AU$365 flight on Tue, 9 Sep. 2025Opens in a new window

Popular airlines from Seattle to South London

  • Air Canada

    Air Canada

  • British Airways

    British Airways

  • Delta

    Delta

  • KLM

    KLM

  • Lufthansa

    Lufthansa

  • United

    United

  • Virgin Atlantic

    Virgin Atlantic

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Cheap Flights from Seattle (SEA) to South London (LON)

Prices were available within the past 7 days for one-way flights and round trip tickets for the period specified. Prices and availability are subject to change. Additional terms apply.

Aer Lingus
Wed, 6 Aug. - Wed, 13 Aug.
SEA
Seattle
LHR
London
AU$730 Return, just found
AU$730
Return
just found
Select Aer Lingus flight, departing Wed, 6 Aug. from Seattle to London, returning Wed, 13 Aug., priced at AU$730 just found
Delta
Wed, 6 Aug. - Wed, 13 Aug.
SEA
Seattle
LHR
London
AU$777 Return, just found
AU$777
Return
just found
Select Delta flight, departing Wed, 6 Aug. from Seattle to London, returning Wed, 13 Aug., priced at AU$777 just found
Virgin Atlantic
Sun, 10 Aug. - Wed, 27 Aug.
SEA
Seattle
LHR
London
AU$779 Return, found 6 days ago
AU$779
Return
found 6 days ago
Select Virgin Atlantic flight, departing Sun, 10 Aug. from Seattle to London, returning Wed, 27 Aug., priced at AU$779 found 6 days ago
Virgin Atlantic
Wed, 6 Aug. - Wed, 13 Aug.
SEA
Seattle
LHR
London
AU$786 Return, just found
AU$786
Return
just found
Select Virgin Atlantic flight, departing Wed, 6 Aug. from Seattle to London, returning Wed, 13 Aug., priced at AU$786 just found
Air Canada
Sun, 10 Aug. - Wed, 27 Aug.
SEA
Seattle
LHR
London
AU$790 Return, found 6 days ago
AU$790
Return
found 6 days ago
Select Air Canada flight, departing Sun, 10 Aug. from Seattle to London, returning Wed, 27 Aug., priced at AU$790 found 6 days ago
United
Wed, 3 Sep. - Wed, 10 Sep.
SEA
Seattle
LHR
London
AU$796 Return, found 5 days ago
AU$796
Return
found 5 days ago
Select United flight, departing Wed, 3 Sep. from Seattle to London, returning Wed, 10 Sep., priced at AU$796 found 5 days ago

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

October is typically the cheapest month to fly

From AU$737 - AU$1,330 per traveller.

Graph displaying average flight prices per month

*Available to Expedia members.