London’s famous taxis (black cabs) can either be booked in advance or hailed on the street or from designated taxi ranks.

Taxi numbers

There is a charge when booking by phone and other terms and conditions may vary so please check when booking.

All taxis are wheelchair accessible and most have a variety of additional features to assist passengers. The fares charged are regulated, and with safety paramount all taxi vehicles and drivers must meet minimum standards (for drivers this includes passing the world renowned 'Knowledge of London' examinations). Licensed vehicles are subject to regular checks by the Public Carriage Office.

http://www.tfl.gov.uk/pco/findaride/taxis.asp