Census director on changes to the 2011 survey
Advertising campaigns to raise awareness of the 2011 national censuses are being launched on Monday.
Census Director Glen Watson said there have been changes which allow people to fill in their census form online for the first time.
The form asks for detailed information including nationality, religious faith and marital status.
Mr Watson told the BBC's Louise Minchin new questions on civil partnerships and stepchildren will be included.