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2011 Census Geography Prospectus

This prospectus sets out the release plans and products which will be available as geographic outputs from the 2011 Census. These products are geographic reference data products and do not contain any statistics.

These reference data include:

  • digital boundaries for the modified set of output areas (OA), super output areas (SOA) and the new workplace zones (WZ)

  • lookup files to enable linkage between the 2001 and 2011 output and super output areas

  • lookup files from the 2011 output areas to a number of 2011 Census output geographies

  • a number of other digital spatial and lookup files

The geography reference data are available to download, along with metadata and user guidance in various formats from the census geography products page

In addition to the 2011 Census geography reference data, there are a number of 2001 geography reference data products for download.


  • 31 May 2012 – Publication of 2011 Census geography prospectus

  • 30 October 2012 – First release of 2011 Census geography products

  • 30 January 2013 – Second release of 2011 Census geography products

First release of census geography

The first release of the boundaries and other geography reference datasets are available to download from Tuesday 30 October, ahead of 2011 Census second release statistical outputs. This includes the modified output areas and super output areas. This timetable will allow geography reference data to be loaded into systems before the statistical release.

Second release of census geography

Some reference datasets were published on 30 January 2013, for example workplace zone boundaries and lookups.  


Digital boundaries – output areas, super output areas and workplace zone boundaries are produced for users to carry out spatial analysis in a Geographical Information System (GIS) or for web mapping. These will be available in Esri shapefile formats.

Digital spatial files – Median population weighted centroids are created for output areas, super output areas and workplace zones.  The centroid is a summary single reference point which represents how the population at census time was spatially distributed and grouped within that OA, lower layer super output area (LSOA) or middle layer super output area (MSOA). The provision of centroids allows users to get consistent and comparable best-fit allocations to a higher geography using a GIS. These will be available in Esri shapefile formats.

Lookup files – There is a lookup from 2001 output areas/super output areas to the new 2011 output areas/super output areas to allow users to compare between data output from 2001 and 2011 geographies.

All 2011 Census estimates for all geographies, including wards, will be best-fitted from output areas in line with the National Statistics Geography Policy.  Therefore a number of lookup files from 2011 output areas to other output geographies will be produced. There will also be lookups from workplace zones and enumeration postcodes (those identified during the census) to other census geographies. Lookups will be supplied in comma separated value (csv) and delimited text file formats.


The spatial geography products (including output area boundaries) will be supplied under Open Government licence and Ordnance Survey Open Data licence.

All other geography reference products will be supplied under the Open Government licence.

Table of geographies

The following output geographies for census will be supported:

Geography Currency Exact/Best-fit No. of instances
Output areas December 2011 Exact-fit


Lower layer super output areas December 2011 Exact-fit


Middle layer super output areas December 2011 Exact-fit


Workplace zones December 2011 Exact-fit


National parks December 2011 Exact-fit 13
Local authority district December 2011 Exact-fit 348
Wards December 2011 Best-fit 8,588
Parishes/communities December 2011 Best-fit 11,360
Counties December 2011 Best-fit 27
Former counties December 2011 Best-fit 34
Regions December 2011 Best-fit 9
Westminster parliamentary constituencies December 2011 Best-fit 573
Primary care organisations December 2011 Best-fit 151
Local health boards December 2011 Best-fit 7
Strategic Health Authorities December 2011 Best-fit 10
National Assembly for Wales constituencies December 2011 Best-fit 40
Local administrative units (LAU) 2 December 2010 Best-fit 8,588
Local administrative units (LAU) 1 December 2010 Best-fit 348
Nomenclature of units for territorial statistics (NUTS) 3 December 2008 Best-fit 105
Nomenclature of units for territorial statistics (NUTS) 2 December 2008 Best-fit 32
Nomenclature of units for territorial statistics (NUTS) 1 December 2008 Best-fit 10
Settlements December 2011 Best-fit To be confirmed
Built-up areas December 2011 Best-fit To be confirmed



Content from the Office for National Statistics.
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