The information requested falls within the responsibility of the UK Statistics Authority. I have asked the authority to reply.
Letter from Karen Dunnell, dated February 2009:
As National Statistician I have been asked to reply to your recent question asking what estimate has been made of the cost of the property database being created for the 2011 Census. (253765)
The cost of developing an Address Register for the 2011 Census is now estimated to be about £12m over the years 2008 - 2011. The additional estimated cost since my reply to your previous question in November 2008 (Hansard reference 235103) is due to a decision following successful piloting to match fully the two key national address lists - the Royal Mail Postal Address File and Local Government's National Land and property Gazetteer.
It is misleading to refer to this as a 'property database' since the Address Register will contain a list of household and communal establishment addresses linked to higher level geographic areas. The pre-requisite for a successful strategy of post-out of Census questionnaires as the primary delivery method, is the availability of a comprehensive, high quality address register for all areas of England and Wales. The Office for National Statistics is developing an address register that meets Census requirements in terms of quality and coverage and which local authorities can be confident will effectively underpin Census enumeration and outputs.