http://www.ukba.homeoffice.gov.uk/uk...dcivilpartner/

When your fiance, fiancee or proposed civil partner arrives in the United Kingdom, he or she will normally be granted permission to stay here for six months, but he/she must not work.

After you have married or registered your civil partnership, you husband, wife or civil partner may apply to stay here. If we approve the application, we will give your husband, wife or civil partner permission to live and work here for two years.