The postcode is the most important component of an address, the structured standard used to deliver mail to households and businesses.
The UK postcode system is hierarchical such that a full, or unit, postcode (AB54 6DX) falls within a postcode sector (AB54 6), which is itself part of a postcode district (AB54) which is in turn part of a much larger postcode area (AB).
Any postcoded data may be mapped using the postcode, typically with an accuracy of around 10 to 100 meters.
Incomplete or out of date postcode or address data may be cleaned (using address management software) prior to mapping, or may be mapped to larger units (eg postcode sectors or districts) in the hierarchy.
Several organisations collate and maintain postal boundary products, including:
Extensive validation and cleansing procedures have been used to ensure that this data set is one of the most accurate available for analysing customer distribution, proximity analysis, retail location or any other mapping at unit postcode level.
Other Geoplan postcode points are derived from the corresponding postal product set of postcode sector, district and area boundaries.
Each point data set is supplied with:
Name (postcode sector, district or area)
Post Town
Ordnance Survey grid reference
Counts of the number of residential, non-residential and large user delivery points
Physical area of the corresponding boundary
In addition, unit postcode points are supplied with:
£500.00 per annum (year 2 on, 2 year minimum contract)
Ordnance Survey Code-Point is a new product providing a precise geographical location for each UK unit postcode.
The Code-Point (for each unit postcode) is derived from the mean of the most accurate address locations in Ordnance Survey's ADDRESS-POINT™ product.
ADDRESS-POINT™ provides each of the 26 million addresses in Britain with a precise geographic reference to a resolution of 0.1 meter. To ensure that the Code-Point centroid stays within the extent of the unit postcode, it is given the coordinates of the nearest reliable address to the mean position.
Each Code-Point record has a postcode and national grid reference together with a number of other attributes:
Positional Quality Indicator (providing information about the accuracy of the postcode location)
PO Box Indicator - flag which indicates whether the postcode contains only PO Boxes
Total number of delivery points (addresses) in the unit postcode
Number of delivery points in ADDRESS-POINT™ with the same 'positional quality indicator' as that allocated to the Code-Point postcode record
Number of residential delivery points in the unit postcode
Number of non-residential delivery points in the unit postcode
Number of PO boxes in the unit postcode
Addressed Building count (indicating whether the postcode is likely to contain flats or offices)
Number of delivery points in ADDRESS-POINT™ not allocated accurate coordinates
Ordnance Survey National Grid coordinates (resolution of 1 meter)
Code-Point is the optimal data set for those applications where the most accurate postcode grid referencing is required.
