> For the complete documentation index, see [llms.txt](https://docs.os.uk/os-downloads/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.os.uk/os-downloads/products/areas-and-zones-portfolio/code-point-with-polygons/code-point-with-polygons-technical-specification/data-supply.md).

# Data supply

The polygon data coverage is Great Britain for all formats; the associated Code-Point points coverage is for the United Kingdom (as it includes Northern Ireland postcodes) for all formats apart from GeoPackage, which is Great Britain coverage only, not Northern Ireland.

## Update currency <a href="#bookmark5" id="bookmark5"></a>

Updates will normally be quarterly in January, April, July and October and are a complete resupply of the national dataset.

## Supply formats <a href="#bookmark6" id="bookmark6"></a>

Code-Point with Polygons is available in the following formats, the preferred choice of which will be influenced by the software you use:

### **ESRI Interchange format Shapefile**

ESRI Shapefile is a simple, non-topological format for storing the geometric location and attribute information of geographic features. A Shapefile is one of the spatial data formats that can be utilised in ArcGIS.

The Shapefile format defines the geometry and attributes of geographically referenced features in as many as six files with specific file extensions that should be stored in the same project workspace.

They are:

* .**shp** – The file that stores the feature geometry.
* **.shx** – The file that stores the index of the feature geometry.
* **.dbf** – The dBASE file that stores the attribute information of features.
* **.prj** – The projection file that provides the information on the coordinate reference system. When a Shapefile is added as a theme to a view, this file is displayed as a feature table.
* **.sbn** and **.sbx** – The files that store the spatial index of the features.

The last two files will only exist if you perform theme on theme selection, spatial joins, or create an index on a theme's SHAPE field.

{% hint style="info" %}
The shapefile has two attributes (FID and SHAPE) that are virtual columns created by ArcGIS when accessing the table contents but are not visible in the attribute table. The FID column uniquely identifies each object stored in the table. The SHAPE column provides information about the feature geometry.
{% endhint %}

### **MapInfo Interchange format (MID / MIF)**

The transfer format is as defined by the MapInfo Professional User's Guide: MIF Export. MapInfo Interchange Format (MIF) is an ASCII file format that can fully describe a MapInfo database. Both graphic and tabular data are exported into MIF files. The graphic data is in a file with a .mif extension, while the tabular data is in a file with a .mid extension.

### **MapInfo Table file format (TAB)**

TAB files (MapInfo tables) are the native format of MapInfo. They consist of a number of files with extensions such as .DAT, .ID, .MAP and .TAB; all of these files need to be present and kept together for the table to work.

### **Vector tiles format (MBTiles)**

Code-Point with Polygons is supplied as a national vector tiles set in a single MBTiles file (combined from individual PBF tiles). This is a lightweight set of tiles that are efficient to render in supported software, provide high-resolution data and give a seamless experience when zooming in and out. The data is supplied in Web Mercator projection (ESPG: 3857).

### **GeoPackage**

Code-Point with Polygons is also supplied as GeoPackage. This is an open, standard, platform-independent, portable, self-describing, compact format for the transfer of geospatial data. GeoPackage is an SQLite container, the contents of which are governed by GeoPackage Encoding Standards.

Since a GeoPackage is a database container it supports direct use. This means that the data in the GeoPackage can be accessed and updated in a 'native' storage format without the need for intermediate format translations. It will effectively 'plug and play' in most GIS packages.

## Supply options <a href="#bookmark7" id="bookmark7"></a>

You can download all formats of Code-Point with Polygons via the [OS Data Hub](https://osdatahub.os.uk/).

## File sizes <a href="#bookmark8" id="bookmark8"></a>

File sizes for the product (including the polygon and points data) are approximately:

* Shapefile: 666MB
* MapInfo MID / MIF: 638MB
* MapInfo TAB file: 568MB
* Vector tiles (MBTiles): 470MB
* GeoPackage (GPKG): 871MB

## Code-Point with Polygons version numbering <a href="#bookmark9" id="bookmark9"></a>

Each edition of Code-Point with Polygons will have a version number showing the release month for the year (for example, April) followed by the release year (for example, 2026).

The version for each quarterly release will be in this format:

* April\_2026
* July\_2026
* October\_2026
* January\_2027

The Code-Point data packaged alongside the postcode polygon data will be the data from the most recent Code-Point product release. Typically, this is the Code-Point release from two months prior. For example, the October 2026 release of Code-Point with Polygons will be supplied alongside the August 2026 release of Code-Point.


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