Our public task

The statement of our Public Task sets out what by law we exist to do.


Ordnance Survey (OS) is Great Britain’s mapping agency, and creates, maintains and disseminates consistent, definitive and authoritative geospatial and cartographic data and products of Great Britain in the national interest.

With effect from 1 April 2015 we have operated as a Government owned limited company, the entire issued share capital of which is held by the Secretary of State for Business, Energy & Industrial Strategy.

This statement describes our current Public Task for the purposes of the Re-Use of Public Sector Information Regulations 2015 (the Re-use Regulations).

Our Public Task

Our Public Task is:

1. To maintain and develop the underlying physical infrastructure which is needed to support mapping applications; including to maintain a national grid and the national geodetic and height frameworks and to link these to international systems.

2. To create, maintain and provide governance for the National Geographic Database (NGD) made up of geographic information datasets with coverage of all of Great Britain to a consistent specification.

3. To make the content of the relevant datasets widely available as products which can be used by customers of all types for a wide range of purposes.

4. To provide advice and support to the UK Government on all aspects of survey, mapping and geographic information (e.g. in relation to national security issues and provision of the Mapping for Emergencies service).

The datasets and products that are created to deliver the Public Task are described in the Annex.

In order to deliver our Public Task we collect and record the following information:

  • The topography and topology of natural and man-made features of the landscape.
  • Descriptive annotations and distinctive names/postal numbers of buildings, places and features.
  • The connectivity of water and communication networks including the routing attribution of road, tracks and paths.
  • The alignment of administrative and electoral boundaries.
  • The extent and classification of certain types of land cover and use.

The Ordnance Survey Act 1841 provides powers to enable the collection of this information.

Access and licensing

As a Government Owned limited company we are obliged to be self-financing and are required to generate revenue to cover all of our costs, including costs relating to the performance of the Public Task. Accordingly, we operate a licensing model by way of recognised exception to the principle of marginal cost pricing as described in The National Archives’ ‘Guide to drawing up a statement of public task’ (Document Version 1.0 published in August 2011).

This licensing model currently includes making OS products available:

(i) Free at the point of use through OS OpenData, a range of products available on similar terms to the Open Government Licence; and

(ii) In accordance with OS’s standard licensing model.

Find details of our products, their specifications, licence terms and relevant licence fees on our licensing web page.

In licensing our products, we are committed to the principles of the Information Fair Trader Scheme, in relation to which we are fully accredited.

Approval and review

Prior to publication this statement has been discussed with and approved by the Shareholder Executive and discussed with the Office of Public Sector Information (OPSI), part of The National Archives. Note that whilst OPSI has provided recommendations which have been taken into account in producing this statement, OPSI does not approve statements of Public Task.

Our Public Task statement will be reviewed at regular intervals, through consultation between OS, the Department for Business, Energy & Industrial Strategy, and OPSI, and with reference to guidelines published by OPSI. We will also consult with and seek contributions from relevant customer and stakeholder groups when reviewing the Public Task statement. 

It is envisaged that our Public Task statement will next be reviewed no later than two years following publication of this version (see below for date of publication).

If you have any queries or wish to make any comments or contributions on our Public Task you may contact us on 03456 05 05 05 or email customerservices@os.uk. In particular, interested parties may challenge this Public Task statement if they believe it to be incorrect in identifying Public Task activities. If you wish to challenge this statement, or to make a complaint about OS under the Re-use Regulations, you may do so using our general complaints handling process. We will deal with any such challenges or complaints in accordance with our IFTS and PSI internal complaints process as set out in our complaints process.

Annex to Public Task statement

This Annex describes the datasets which have been produced in order to deliver the Public Task and the products that are currently (as at the date of publication or latest revision of this Public Task) their direct output, which together comprise the Public Task information for the purposes of the Re-Use of Public Sector Information Regulations 2015 (the Re-use Regulations).

Note that we operate a commercial licensing model, which currently includes making products available:

(i) Free at the point of use under the Public Sector Mapping Agreement
“PSMA” (to the public sector in England and Wales) and One Scotland Mapping Agreement “OSMA” (to the public sector in Scotland).

(ii) Free at the point of use to all on the terms of the Open Government Licence v3.0; and

(iii) In accordance with OS’s standard commercial licensing model.

All products contained in the table below are either included in the PSMA and/or OSMA, or made available as Open Data under the terms of the Open Government Licence, save for OS Net services, OS Terrain 5, and the OS Explorer and OS Landranger Map series.

Published on 1 February 2016.

Public Task Dataset

Brief description of Dataset

Products currently produced from the Dataset which are within the Public Task



Precise Positioning Data

A dataset of real time readings taken from a network of permanent GNSS receivers across Great Britain. The combined data is used to generate corrections that enable precise positions to be defined by a GNSS roving receiver.

OS NET services


Content and unique identifiers regarding the topography of Great Britain, ‘topography’ meaning the surface shape and composition of the landscape, comprising both natural and artificial features. Constitutes the only nationally topologically consistent, fully maintained and authoritative large scale topographic data available for the whole of Great Britain.

Populated directly from surveys collected at precisions and root mean square error accuracy (RMSE) of:

  • Urban areas 0.4m;
  • Rural areas 1.1m; and
  • Mountain and moorland 4.2m.

OS MasterMap® Topography Layer

Communications Networks

Authoritative, geometrically precise and nationally consistent large scale communications (road, track and path) network data together with traffic flow, height and weight restriction attributes for all of Great Britain. The dataset comprises:

  • Roads network data; and
  • Urban Path network data.

OS MasterMap®
Integrated Transport Network layer
OS MasterMap® Networks – Water Layer
OS Open Rivers
OS Open Roads


Authoritative and fully maintained database of precisely grid referenced addresses providing consistently attributed detailed data for the whole of Great Britain, and forming the core addressing content of NGD, and containing Land and Property Address Data.

AddressBase™ Plus
AddressBase™ Premium
OS MasterMap Address Layer
OS MasterMap Address Layer 2
Code-Point with Polygons
Code-Point Open
OS Locator
1:50 000 Scale Gazetteer
OS Open Names

National Height data

The Integrated Digital Terrain Model (iDTM) contains information about the terrain and features of Great Britain. It is an authoritative and nationally consistent dataset stored and maintained in three dimensions as a Triangulated Irregular Network (TIN). 

The model is accurate to RMSE of 1.5m in urban areas, and 2.5m in rural areas and mountainous and moorland regions.

The height model has been interrogated to output digital terrain models (bare earth) at two resolutions with horizontal resolutions of 5 metres and 50 metres respectively.

OS Terrain 5
OS Terrain 50


Administrative Boundaries

The authoritative reference dataset of administrative area polygons complementing other formal management (e.g. health service; utility services) and statistical analysis areas.

The data is derived from the surveyed alignments and Boundary Order attribution contained within the NGD Topography, and presented at a resolution commensurate with a nominal scale of 1:10,000, comprising:

  • European and UK Parliamentary Constituency Boundaries within Great Britain;
  • National Boundaries within Great Britain; and
  • Local Authority administration boundaries.


Mid-Scales Databases

Datasets derived from the large scale topographic database using nationally consistent generalisation rules.

OS VectorMap Local Vector
OS VectorMap Local Raster
OS StreetView
OS VectorMap District Vector
OS VectorMap District Raster
1:25,000 Scale Colour Raster
OS Open Map Local
OS Explorer Map series 

1:50,000 Scale Height data

A database of contours created from height elements depicted in the OS Landranger 1:50 000 scale map series. These were originally generated from stereo aerial photography flown during the 1970s.

  • Contours: 10m vertical interval – national cover with an accuracy of 3.0m RMSE; and
  • Digital Terrain Model with a 50m horizontal rectangular grid.

Land-Form PANORAMA® Contours

1:50,000 Scale Database

The database underlying and originally derived from the OS Landranger national map for general wide area topographic location and reference.

1:50,000 Scale Colour Raster
OS Landranger Map series

Small-Scales Vector database

A multi-sourced geographical reference dataset at a nominal scale of circa 1:50,000.


1:250,000 Scale Database

Consistent national small scales database of communications, settlements, major hydrology and significant vegetation providing selected topographic information at the regional level.

1:250,000 Scale Colour Raster
Administrative Boundary Maps

1:1,000,000 dataset

A simple graphical dataset of Great Britain with geographical and topographical content appropriate to a small scales national geographical overview map.