Documentation

The GeoConvert tool outputs geographic codes, and not the associated names. This page contains the name and code look up tables for the geographies used in GeoConvert.

2011 codes and names

The InFuse 2011 geography page contains all of the relevant codes and names.

2001 codes and names

1991 codes and names

Other useful content

Deprivation measures

GeoConvert provides deprivation scores and ranks for each country via the Information about Postcodes function. Users of the tool can upload their postcodes to find a postcodes Lower Super Output Area deprivation score or rank. It's important to note that these measures of deprivation are not based on an actual postcode but on the larger geography LSOA. GeoConvert simply tells you the measure of deprivation for a postcodes LSOA.
Each of the four nations across the UK produces an index of multiple deprivation, GeoConvert uses the index of multiple deprivation produced by each of the four nations that make up the UK:

There is no single UK-wide index of multiple deprivation. Each nation has developed a distinct IMD, designed to identify small area concentrations of multiple deprivation as best as possible within that nation. This provides challenges for researchers wishing to compare deprivation across the UK.
See the following articles which explore these issues:

Area classifications

As the name would suggest these are based on 2011 Census output areas. GeoConvert will simply give the Area Classification for the uploaded postcodes Output Area.

Urban/rural classifications

Different urban/rural classifications have been produced by the three census agencies for different countries of the UK at different dates. GeoConvert supplies them across the UK. The classifications vary in their methodologies, numbers of categories, dates of creation and the geographies for which the classifications were generated. Users should beware of comparing areas across different classifications.

GeoConvert matches supplied postcodes to the smallest geographic areas for which each of the classifications were produced, and provides the values of the most detailed urban/rural classifications for those areas. The classification values do not relate to individual postcodes.

Brief details of different the urban/rural categories are provided below. Further information about the classifications can be found by following the links.

England and Wales: 2011 rural/urban classification for small-area geographies

This classification was published in August 2013. It has 10 categories. Values obtained for postcodes from GeoConvert are for the 2011 census output areas to which the postcodes are matched.

Northern Ireland: Urban-Rural Classification (2005)

This classification was published in February 2005. It has 8 categories. Values obtained for postcodes from GeoConvert are for the 2001 census output areas to which the postcodes are matched.

Scotland: Scottish Government Urban Rural Classification 2013-2014

This classification was published on 28 November 2014. It has 8 categories (which can be collapsed to 6, 3 and 2 category classifications). Values obtained for postcodes from GeoConvert are for the 2001 census output areas to which the postcodes are matched.

Postcode information

Postcode population estimates

Estimates of the number of usual residents and the number of households with at least one usual resident for enumeration postcodes. Each of the three census agencies produced different sets of information, the key features of which are described below, along with links to more detailed information.

  • Postcodes in England and Wales

    The Office for National Statistics (ONS) released counts of the numbers of usually resident people, males, females and households. Further information is available from the ONS website.

  • Postcodes in Northern Ireland

    The Northern Ireland Research and Statistics Agency (NISRA) released counts of the numbers of usually resident people, males, females and households, but supressed (did not release) counts for approximately 12 percent of postcodes that had fewer than four usually resident households and ten usually resident persons. Summary counts of 'missing' populations were provided by postcode sector, and these were reallocated evenly to suppressed postcodes within sectors as part of the processing of data for GeoConvert. Further information is available from the NISRA website.

  • Postcodes in Scotland

    National Records of Scotland (NRS) released counts of the numbers of usually resident people and households, but no counts of usually resident males and females. Further information is available from the NRS website.

Figures may not sum to the published figures for OAs in all cases due to differences in postcode to OA allocation methods.

Postcode centroid source
The version of Office for National Statistics Postcode Directory (ONSPD) from which the postcode centroid was obtained, or alternative source of centroids in a very few cases. See section on postcode centroid quality measure below for further information.

Postcode centroid quality measure
Each grid reference is given a Positional Quality Indicator (PQI) to denote the accuracy of its grid reference:

  1. Within the building of the matched address closest to the postcode mean.
  2. As for 1 above, except by visual inspection of Landline maps (Scotland only).
  3. Approximate to within 50 metres.
  4. Postcode mean (mean of matched addresses with the same postcode, but not snapped to an address).
  5. Imputed by ONS, by reference to surrounding postcode grid references.
  6. Postcode sector mean (mainly PO Boxes).
  7. Terminated postcode. Last known ONS grid reference used.
  8. No co-ordinates available.

Initial values were taken from the May 2011 version of the ONSPD. Where the values were > 1, postcodes were matched against successive ONSPD versions, and centroids replaced by those with lower values of if they existed, continuing until value = 1.

Postcode centroid easting and northing values
Easting and northing coordinates were obtained for centroids of the set of enumeration postcodes used in GeoConvert from versions of the Office for National Statistics Postcode Directory (ONSPD). The ONSPD provides centroid coordinates for postcodes in England, Scotland and Wales in British National Grid (OSGB 1936 / EPSG:27700) projection, and for postcodes in Northern Ireland in Irish Grid (TM65 / EPSG:29902) projection. Coordinates for all postcodes across the UK were transformed to a consistent Latitude/Longitude (WGS84 / EPSG:4327) projection for processing for use in GeoConvert.

Postcode census agency
The census agency that supplied population information for the postcode (ONS, NRS or NISRA).

Postcode date of introduction
The most recent occurrence of the postcode's date of introduction.

Postcode date of termination
Postcodes are frequently terminated by Royal Mail for a variety of reasons, but most commonly due to the demolition/re-development of buildings or to postcode reorganisations. If a value is present, this is the most recent occurrence of the postcode's date of termination. If no value is present, the postcode was live at the date of the version of the Office for National Statistics Postcode Directory indicated by the Postcode centroid source variable.

Postcode user type
Indicates whether the postcode is a small user (value = 0) or large user (value = 1) postcode.

GeoConvert is provided by UK Data Service