Ordnance Survey OpenData

The Ordnance Survey (the UK's national mapping agency) began releasing data for free re-use on 1 April 2010 following a Government Consultation.

Between 2010 and 2015, the data was licensed under the Ordnance Survey OpenData Licence with OS confirming with OpenStreetMap's Licensing Working Group that mapping derived from OS OpenData products (though not CodePoint Open, and not other products released by third parties under the OS OpenData Licence) can be released under the Open Database License 1.0. (statement). In February 2015, OS replaced the OS OpenData Licence with version 3 of the Open Government Licence (OGL). This brings it in line with other government open data releases and continues to allow the data to be used in OpenStreetMap.

Using the data in OSM

Editing Guidelines

Several tools have been made available to help OpenStreetMappers use this data. These are discussed below. However before you start editing, please consider the following:

Don't assume the OS data is either correct or up to date. Use it as a guide and additional resource for your mapping, not a replacement.
Please add source tags to any data you add to OSM from OS OpenData. See the tag suggestions: #Attributing OS
If you're tempted to map in an area you're not familiar with, contact any local contributors first. Please don't alienate other contributors by treading on their toes. They will know their local area better than anyone else.
Look for places that have been mapped using aerial imagery and don't have road names. This is a good place to start.
Avoid simply duplicating OS data in blank areas of OSM unless you're familiar with the area and don't have access to other resources such as a GPS.

New ideas and automated imports

If you have any new ideas on what to do (and what not to do) with the data, and solving issues like accuracy, how to avoid duplicates, etc. please go to the talk-gb mailing list before trying to import any OS data into OSM. You may also like to take a look at previous discussions from April 2010 and current ideas on the 'Talk' page:

Attributing OS

We have a generic attribution relating to Ordnance Survey OpenData products on the Contributors page

However all OSM contributors are encouraged to add specific source information on tags when they use OS OpenData products as the primary source of information for the object being added to OSM.

Tag suggestions:

When tracing over OS StreetView

When everything is derived from OS StreetView source=OS_OpenData_StreetView
When just the name is derived from OS StreetView source:name=OS_OpenData_StreetView
This icon might be useful for a JOSM preset to apply source tags

When using OS Locator for names

source:name=OS_OpenData_Locator

When adding OS vector data

Choose an appropriate tag for the object based upon the OS OpenData product. For example source=OS_OpenData_BoundaryLine

When using OS VectorMapDistrict

source=OS_OpenData_VectorMapDistrict

Available data (in alphabetical order)

There are a number of Ordnance Survey data products available via the OS Data Hub. They are supplied under the UK Open Government Licence (OGL) and require an attribution statement along the lines of "Contains OS data © Crown copyright and database right 2017". Data is generally supplied in Vector GML 3.2 or ESRI Shapefiles and can be selected by grid square. Rasters are sometimes available. They are often generalised layers suitable for background tile display but not detailed enough for full analysis. A paid-for product will be available for the detailed data.

See OS Find the right business product for full descriptions and download links.

Boundary-Line

GB local government administrative boundaries, electoral boundaries and coastline (high_water_polyline).

Scale: 1:10,000 (Print), 1:5,000 to 1:8,000 (Screen)
Supply format: ESRI® Shapefile
Update cycle: Six-monthly, May and October
Coverage: England, Scotland, Wales
Reprojected GPX files for counties, unitary authorities, districts, civil parishes (England), communities (Wales) and high-water line (coastline) for the whole of Great Britain (not including Northern Ireland!) can be found here: https://csmale.dev.openstreetmap.org/os_boundaryline/ (Updated to October 2024)

Code-Point Open

Locations of every GB postcode centroid.

Useful for geographical analysis, simple route planning and asset management. Data contains postcodes, grid references, NHS® health and regional health authority codes; administrative ward, district, county and country area codes. PDF includes differences between Code-Point and Code-Point Open.

Scale: 1 metre resolution for postcode central position
Supply format: CSV (comma separated values: a text file), GeoPackage
Update cycle: Quarterly, February, May, August and November
Coverage: England, Scotland, Wales
Link: https://www.ordnancesurvey.co.uk/products/code-point-open

The structure of the Code-Point-Open data format is hidden away on the OSGB site. Information about the fields can be found on the data.gov.uk wiki ^{[ dead link ]}

See also: ONS Postcode Directory

CodePoint Tiles

Chillly has rendered codepoint tiles which you can load into your favorite OSM editor. All of the GB codepoint data has been rendered into tiles. See https://codepoint.raggedred.net/ for more details.

For JOSM add a custom TMS url as follows:

'Edit' menu -> 'Preferences...'
Click 'WMS/TMS' tab on the left
Click the '+ TMS' button
Enter in the URL box the following text string: https://www.raggedred.net/tiles/codepoint/{zoom}/{x}/{y}.png
Enter 'CodePoint Postcodes' as the menu name
'OK'
'OK'

Now you can select the layer from the "Imagery" menu.

There are also Office of National Statistic Postcode Data (ONSPD) tiles available. More information see https://onspd.raggedred.net/

Comparison of OSM and Code-Point Centroids

Robert Whittaker provides a Postcode Stats tool, which indicates proportions of postcode units that are mapped, shows the centroid locations from Code-Point Open, and the mean position of the OSM objects with each postcode.

GB Overview Maps

Very high-level map in two versions: roads and cities, or terrain.

MiniScale

Smallest scale data provided. Shows broad landscape features including boundaries, settlements, main communications and physical features.

Scale: 1:1,000,000 (Print), 1:700,000 to 1:2,000,000 (Screen)
Supply format: TIFF LZW (image) (Also JPEG?)
Update cycle: Annually, January
Coverage: England, Scotland, Wales
Link: http://www.ordnancesurvey.co.uk/oswebsite/products/miniscale/

OS Locator

OS Locator data displayed in Potlatch2 using ITO World's OSM and OSL differences tileset

Gazetteer of road names. Contains coordinates to create a rectangle encompassing the extent of the road referenced in the gazetteer.

Scale: 1:10,000 (Print), 1:7,000 to 1:10,000 (Screen) Contours at 10m intervals.
Supply format: CSV (values separated by a colon ":" - not a comma separated file!)
Update cycle: Six-monthly, April and November
Coverage: England, Scotland, Wales
Link: http://www.ordnancesurvey.co.uk/oswebsite/products/os-locator-opendata/ ^{[ dead link ]}

This gazetteer appears to complement the StreetView data - some (short) streets whose names are absent from StreetView are included in OS Locator. Conversely, some streets named in StreetView are absent from OS Locator

OSM and OSL differences analysis was a useful tool for OSMers allowing you to compare each district's coverage. It was built by ITO World using the OS Locator dataset. See OS Locator page for more details, tools and uses of this dataset.

OS MasterMap Property Extents (TBC)

On June 2018 the OS announced in the article Unlocking of Government’s mapping and location data to boost economy by £130m a year that key parts of the Ordnance Survey (OS) MasterMap freely available will help businesses use geospatial data more easily and drive innovation across the UK economy.

MasterMap is OS's most detailed product therefore this data would be suitable for risk analysis, etc.