The British Union of Fascists (BUF) was a British fascist political party formed in 1932 by Oswald Mosley. Mosley changed its name to the British Union of Fascists and National Socialists in 1936 and, in 1937, to the British Union. In 1939, following the start of the Second World War, the party was proscribed by the British government and in 1940 it was disbanded.

British fascism is the form of fascism which is promoted by some political parties and movements in the United Kingdom. It is based on British ultranationalism and imperialism and had aspects of Italian fascism and Nazism both before and after World War II.