🔃OS NGD Administrative and Statistical Units
Introduction to the theme
Administrative and Statistical Units are the geographical extent of administrative, legislative, regulatory, electoral, statistical, governance, service delivery and activity management areas. OS NGD Administrative and Statistical Units Theme data is the most comprehensive and high-quality set of area data available for Great Britain ever produced by OS. You can use the datasets to perform quick and accurate searches as well as high-level visualisation and spatial analysis of features.
The OS Boundaries Collection provides a definitive dataset of administrative and electoral boundaries and their names for England, Wales and Scotland. Government Statistical Service (GSS) codes are contained within the data and are supplied by the Office for National Statistics (ONS) and the National Records of Scotland (NRS).
As of the end of March 2026, the theme now also includes the OS Functional Areas, OS GB Postcodes and OS NI Postcodes Collections. These are notional geographies which have been algorithmically derived from other OS NGD data.
The three new retail areas feature types in the OS Functional Areas Collection define the notional geographic extents of retail locations across Great Britain, identifying clusters of buildings with retail addresses.
The two postcodes collections provide complete, analytical and authoritative postcode datasets for Great Britain and Northern Ireland; they are designed to provide a detailed view of postcodes. Full UK postcode coverage is available if you combine data from the two collections as the identical schemas enable compatibility.
Data structure
The OS NGD Administrative and Statistical Units Theme is made up of four collections, which in turn are comprised of 23 feature types. The four collections are OS Boundaries, OS Functional Areas, OS GB Postcodes and OS NI Postcodes.
Unique identifiers
At least one of the following four unique identifiers is provided with each feature within the OS NGD Administrative and Statistical Units Theme:
OSID (Ordnance Survey Identifier): The primary identifier and unique key for feature types in the OS Boundaries Collection.
TOID (Topographic Identifier): An additional secondary identifier for feature types in the OS Boundaries Collection which can aid further data linking. TOIDs are an optional attribute and therefore will not always be provided with every feature.
🆕 Feature ID: For a small number of feature types in OS NGD where it is not possible or necessary to have identifiers that persist over time, the Feature ID is used as the primary identifier. The Postcode Unit Area, Retail Area Aggregated, Retail Area Major and Retail Area Minor Feature Types in this theme use this unique identifier. The notional extents of the retail area features and Postcode Unit Area features are regenerated periodically (for example, monthly for the latter), at which point all features will get a new Feature ID.
🆕 Postcode: The primary identifier for the Postcode Unit Point Feature Types and an important identifier for the Postcode Unit Area Feature Type in this theme (Postcode Unit Area features represent postcode parts, not whole postcodes, so their primary identifier is Feature ID). Postcode is the identifier assigned by Royal Mail for the purposes of mail delivery. A postcode is an abbreviated form of address, made up of combinations of between five and seven alphanumeric characters. These alphanumeric characters are used by Royal Mail to help with the automated sorting of mail. A postcode may cover between 1 and 100 addresses.
🆕 Geometry ID: A non-persistent identifier currently used in the Postcode Unit Area Feature Type only, to identify where postcode part geometries are coincident. Some of the OS NGD feature types are designed for multiple features to have exactly the same polygon, called coincident geometries. For example, a residential tower block represented by a single building may have hundreds of addresses located in it with several different postcodes. In this scenario, a Postcode Unit Area feature would represent each postcode as an area (called a postcode part), all of which would share the same geometry (derived from the building representing the tower block). All of the coincidental geometries would have the same Geometry ID. The Geometry ID is used to identify which other features share that same geometry and it can support key use cases (for example, it can be used to create a full surface representation of postcode unit areas). Metadata about the number of coincident geometries is supplied.
GSS (Government Statistical Service) codes: A system of referencing for administrative, electoral, and statistical geographies.
Please note that Boundary High Water Mark, Ceremonial County, Historic County, Historic European Region, and Polling District features in the OS Boundaries Collection do not have GSS codes or TOIDs allocated to them; however, they do have OSIDs allocated to them. Polling District features have an additional unique identifier of Polling District Identifier.
Useful links
The following introductory guides (covering the benefits, key features and attribution available for each collection) are available on our More than Maps site:
Identify retail locations: Find out how the new retail areas data is useful for central government in the creation of policy relating to local neighbourhoods and can be used to show how investment impacts areas with similar characteristics. Discover how local authorities can use this foundational dataset for evidence-gathering and to define patterns of economic activity.
Last updated
Was this helpful?