The GSS Coding and Naming policy for some statistical geographies was implemented on 1 January 2011. From this date, where new codes have been allocated they should be used in all exchanges of statistics and published outputs that normally include codes.
The Register of Geographic Codes (RGC) summarises the range of area instances within each geographic unit and is available free of charge to download from the 'Open Geography portal'.
The Code History Database (CHD) provides multiple functionality including details of all codes, relationships, hierarchies and archived data. Initially, the CHD was used in parallel with the Standard Names and Codes (SNAC), the UK Statistical Geographies Database (SGDB) and the Ward History database. These have been reviewed and the 2010 version of the Ward History Database is now a frozen, historical document. The 2010 SNAC is the last full version but a condensed 2011 version is available. The SGDB will continue to be produced and includes geographies that are not available from the CHD.
The CHD is in available to download free of charge from the 'Open Geography portal' as a zip file containing an MS Access database. Within the 'Open Geography portal', there are also zip files containing csv tables, for those that do not have MS Access as part of their desktop.