There is at least one major Fascist Party in each nation that ever made up the United Kingdom. Here is a list of them.
England was ruled by the English Union of Fascists under Dictator-General Oswald Mosley, who was assassinated in the end of World War II and ended up with England being placed under occupation. It has been outlawed in England and the UK.
Wales' Fascist Movement has slowly been gaining power since 1993. Bryan Etley is the current party leader and holds a Parliament Seat. It is part of the Greater Union of Fascists. It was created in 1936.