This page explains where you can obtain information on whether or not you need a visa to to come to the United Kingdom and how you should apply for one.
You can get more information on visa requirements and applications on the visa services website or from your nearest British diplomatic post.
You can find the contact details for your nearest diplomatic post on the Foreign and Commonwealth Office website.
A British diplomatic post is a United Kingdom embassy, high commission or consulate.
Visa services, Foreign and Commonwealth Office, King Charles Street, London, SW1A 2AH. If you are outside the United Kingdom you should contact you nearest British diplomatic post.