Range from the cheapest Fit a new plug socket £100 (JJR ELECTRICAL LTD based in SE10) to the dearest Fit a new plug socket £210 (BSS Electrical based in SW9).
Comparing electricians estimates for a Fit a new plug socket gives you an idea of who will be better value but the best way to compare costs is to get actual quotes.
What to do - Get rates and quotes by posting your job to fit a plug socket to electricians in SE15.