> 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/boundary-line/boundary-line-overview/product-supply.md).

# Product supply

## Available formats <a href="#id-1.3-available-formats-for-boundary-line" id="id-1.3-available-formats-for-boundary-line"></a>

Boundary-Line is available in the following formats:

* Esri shapefile
* MapInfo TAB file
* GeoPackage
* Geography Markup Language (GML)
* Vector tiles (MBTiles)

## Coverage <a href="#id-2.3-coverage" id="id-2.3-coverage"></a>

Coverage is Great Britain only.

## Supply mechanism <a href="#id-1.4-boundary-line-supply-mechanism" id="id-1.4-boundary-line-supply-mechanism"></a>

Boundary-Line can be freely downloaded under the [Open Government Licence](https://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/). Data can be downloaded in various formats from the [Ordnance Survey Data Hub](https://osdatahub.os.uk/data/downloads/open/BoundaryLine).

## Product update schedule <a href="#id-1.5-boundary-line-update-schedule" id="id-1.5-boundary-line-update-schedule"></a>

Boundary-Line is updated twice a year, in spring and autumn, allowing a choice as to which update is preferred.

The spring update represents boundaries (as defined and modified by Orders, Acts and Statutory Instruments) at the date of the May local elections.

The autumn update also represents boundaries at the date of the May local elections and is operative from the previous spring / May to autumn / October release.

Unlike changes to other boundaries, changes to Westminster constituency (parliamentary) boundaries do not come into operation on a defined date, and it is therefore difficult to timetable such changes into the spring or autumn updates. Therefore, any forthcoming Westminster constituency (parliamentary) boundary changes that have been approved by Government will be supplied as a separate file (in MapInfo TAB or Esri shapefile formats only) as part of the updates until they are included in the product.


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