Can You Use a Schengen Visa to Visit London? No.

No. A Schengen visa does not grant entry to the United Kingdom. The UK is not part of the Schengen Area (26 European countries with open internal borders). The UK maintains its own separate visa policy. Travelers who need a visa for the UK must apply for a UK Standard Visitor Visa (or other appropriate UK visa) separately, even if they hold a valid Schengen visa.