• The CHD provides details of codes, relationships, hierarchies and archived data.

  • Listings of current lookups for a wide range of geographies in the UK.

  • Current names and codes for a wide range of geographies in the UK, including administrative, electoral, health, international and statistical geographies.

We provide a range of products to define names and codes, and the relationships between geographies. You can find the Government Statistical Service (GSS) Coding and Naming Policy, implemented on 1 January 2011, under ‘Related Links’.

You can download all these products free of charge from the Open Geography portal.