An open dataset containing all Unique Street Reference Numbers (USRNs) from OS MasterMap Highways Network with a simplified line geometry.

A USRN is a unique and persistent identifier for every street, road, track, path, cycle track or cycle way in Great Britain.

How to get this product

Access to this product is free through the OS Data Hub.

Useful resources

• OS Open Identifiers Family Information – This page gives context and information about the OS Open Identifiers 'Family' of products, including explaining what identifiers are and introducing the OS identifiers (TOID, UPRN and USRN). We recommend referring to this page in combination with the Overview and Technical Specification documents for OS Open USRN.

OS Open USRN – November 2024 release note

This release note provides information about the November 2024 release of OS Open USRN.

OS Open USRN – October 2024 release note

This release note provides information about the October 2024 release of OS Open USRN.

OS Open USRN – September 2024 release note

This release note provides information about the September 2024 release of OS Open USRN.

OS Open USRN – August 2024 release note

This release note provides information about the August 2024 release of OS Open USRN.

OS Open USRN – July 2024 Release note

This release note provides information about the July 2024 release of OS Open USRN.

OS Open USRN – May 2024 Release note

This release note provides information about the May 2024 release of OS Open USRN.

OS Open USRN – April 2024 Release note

This release note provides information about the April 2024 release of OS Open USRN.

Source data currency

The following information relates to the currency of the source data used in the creation of this release of OS Open USRN:

Feature count

Next release

The next release of OS Open USRN is scheduled for December 2024.

Source data currency

The following information relates to the currency of the source data used in the creation of this release of OS Open USRN:

Feature count

Next release

The next release of OS Open USRN is scheduled for August 2024.

Source data currency

The following information relates to the currency of the source data used in the creation of this release of OS Open USRN:

Feature count

Next release

The next release of OS Open USRN is scheduled for May 2024.

Source data currency

The following information relates to the currency of the source data used in the creation of this release of OS Open USRN:

Feature count

Next release

The next release of OS Open USRN is scheduled for June 2024.

Product overview

OS Open USRN is an open dataset of all Unique Street Reference Numbers (USRNs) within , with an associated simplified line geometry representing the geographic extent of each USRN.

This product has been designed to enable users to easily share information held against a USRN with a location and to link together information associated with USRNs, enabling location-specific visualisation and analysis.

Product structure

OS Open USRN is a vector dataset with a single line feature for each USRN. Each of these features will have accompanying attribution and a simplified line geometry.

The following pages will detail the attribution held against the features in this dataset and provide further information about the source and simplification of the geometry.

Index

This technical specification includes the following sections:

The OS Open USRN product uses the British National Grid (BNG) coordinate reference system (CRS).

BNG uses the OSGB36 (EPSG 27700) geodetic datum and a single Transverse Mercator projection for the whole of Great Britain. Positions on this projection are described using Easting and Northing coordinates in units of metres. The BNG is a horizontal spatial reference system only; it does not specify a vertical (height) reference system.

Please view our 'Guide to Coordinate Systems in Great Britain' for more information on CRSs.

Available format

This product is only available in GeoPackage format. It is supplied as a single GeoPackage for the whole of Great Britain.

GeoPackage overview

GeoPackage (GPKG) is an open standard data format as defined by the Open Geospatial Consortium (OGC). GeoPackage is designed to be a lightweight format that can contain large amounts of varied and complex data in a single, easy-to-distribute and ready-to-use file.

Please be advised that older versions of GIS software may need updating before being able to display and interact with GeoPackage files.

GeoPackage offers users the following benefits:

• The single file is easy to transfer and offers the end-user a rich experience.

• Attribute names are not limited in length, making it user-friendly.

• The file size limit is very large at 140TB, so lots of data can be easily accommodated (please note that a file size limit may be imposed by the file system to which the file is written).

• It supports raster, vector and database formats, making it a highly versatile solution.

• It is an OGC standard.

• In most cases, it is a plug and play format.

For information on how to open, use and understand a GeoPackage dataset, please refer to our ‘Getting Started with GeoPackage’ guide. Further detailed information on GeoPackage can be taken from the GeoPackage website.

Supply mechanism

OS Open USRN is supplied as a free online download and is available without registration from the OS Data Hub.

Coverage

This product covers Great Britain and includes all USRNs which are present in OS MasterMap Highways Network.

OS Open USRN is available as a Full Supply only. Areas of interest (AOI) orders and Change-Only Updates (COUs) are not available for this product.

Currency

The product will be refreshed on a monthly basis (in-line with the OS MasterMap Highways Network product release on the first working day of each month).

OS Open USRN is an open dataset of all Unique Street Reference Numbers (USRNs) within OS MasterMap Highways Network, with an associated simplified line geometry representing the geographic extent of each USRN.

This product has been designed to enable users to easily share information held against a USRN with a location and to link together information associated with USRNs, enabling location-specific visualisation and analysis.

Local authorities have a statutory responsibility that means they are the source of information for both street naming and managing the highways / roads network. Each authority is provided with a USRN range that is centrally allocated and managed by GeoPlace in England and Wales, and by the Improvement Service in Scotland.

Key features

The key features of the OS Open USRN product are:

• Inclusion of all live USRNs published within the OS MasterMap Highways Network, including Type 1, 2, 3 and 4 streets.

• A simplified line geometry representing the geographic extent of each street, with a single line feature for each USRN.

• Attribution that includes the USRN identifier and Street Type.

Product applications

OS Open USRN enables users to:

• Share information held against a USRN with a location.

• Link together information associated with USRNs.

• Conduct location-specific visualisation and analysis.

This product has not been designed to be used for the street or road works statutory processes where the necessary additional detail for coordination is found in either the National Street Gazetteer (NSG) for England and Wales or the Street Gazetteer for Scotland. Nor does the product provide a topologically structured network suitable for road routing, where the additional detail and complexity provided in OS MasterMap Highways Network is required.

Index

This overview includes the following sections:

• Product supply

• Coordinate reference system

Source data currency

The following information relates to the currency of the source data used in the creation of this release of OS Open USRN:

Feature count

Next release

The next release of OS Open USRN is scheduled for September 2024.

Source data currency

The following information relates to the currency of the source data used in the creation of this release of OS Open USRN:

Feature count

Next release

The next release of OS Open USRN is scheduled for November 2024.

Source data currency

The following information relates to the currency of the source data used in the creation of this release of OS Open USRN:

Feature count

Next release

The next release of OS Open USRN is scheduled for October 2024.

These pages describe the single feature type (OS Open USRN) available for the OS Open USRN product. The attributes associated with the feature type are listed on the following page. The following information is given for each attribute.

Feature type attribution information

Name and definition

The name of the attribute and what it is describing.

Attribute type

The nature of the attribute (for example, a numeric value).

Size

The maximum length of the values in the attribute.

Multiplicity

Describes how many times this element is expected to be populated in the data. An attribute may be optional or mandatory within the OS Open USRN product and this is denoted by:

• '1’ – Mandatory: There must be a value.

• ‘0..1’ – Optional: If populated, a maximum of one attribute will be returned.

A USRN is assigned to the complete street feature and is made up on junction-to-junction segments. It is mandatory for all USRNs to be assigned a Street Type. All streets must have a Type 1 or a Type 2 USRN assigned, but a Type 3 or Type 4 USRN can also represent the same sections of carriageway that the Type 1 or 2 are assigned to.

Street Type definitions table

The following table provides the definitions for different Street Types:

Street Type values table

The following table provides the definitions for Street Type values:

OS Open USRN attributes

The following sub-sections provide details about the attributes included with the single feature type (OS Open USRN) in the product:

id

A non-persistent integer which is autogenerated and is required within the OGC GeoPackage format.

• Type: Integer

• Multiplicity: [1]

usrn

Unique Street Reference Number (USRN), a unique and persistent identifier assigned by the Roads or Highway Authority.

• Type: Integer

• Size: 8

• Multiplicity: [1]

street_type

The type of Street assigned by the Roads or Highway Authority.

• Type: Text

• Size: 35

• Multiplicity: [1]

geometry

The aggregated geometry of either matched OS Road Links or the Elementary Street Units.

• Type: Geometry (MultiLineString)

• Multiplicity: [1]

A JSON (JavaScript Object Notation) file containing version information will be supplied with the product, including the information given in the table below:

The line geometry provided for each USRN is an aggregation of multiple links to ensure that there is a 1:1 relationship between the USRN and a feature. Each USRN will be represented by a single line feature and each line feature will have a single USRN identifier.

OS Open USRN will include geometry sourced from both Ordnance Survey and Roads or Highways Authorities. Where possible, the geometry of streets captured by a Roads or Highway Authority is spatially matched to the geometry of OS Road Links and Path Links. Where this match is successful, OS geometry is used as the source geometry to represent the extent of the Street. Where spatial matching cannot match the geometry captured by the Roads or Highway Authority to OS geometry, the Roads or Highway Authority geometry is used as the source geometry to represent the extent of the Street. Using a combination of geometry sourced from OS and the Roads or Highway Authorities results in all USRNs being spatially represented in OS Open USRN.

Geometry simplification

Geometry simplification is the process of reducing the scale and complexity of the data whilst maintaining the important elements and characteristics of the features. The line geometry provided for each Street has been simplified to ensure that it provides the most suitable geometry for the purposes of openly sharing and linking information against the USRN, whilst ensuring the integrity of the USRN representation.

This simplification means that:

• The number of vertices representing the curvature of streets has been reduced.

• Short cul-de-sacs and slip roads are not supplied.

• Complex configurations of the road network are represented by a simplified depiction, such as large roundabouts, complex junctions and traffic islands.

This simplification process will never result in the loss of complete USRNs; all features with a unique USRN will not be removed.

Due to the generalisation of the geometry, we recommend a viewing scale range of 1:15 000 to 1:30 000.

Overlapping geometry

It is to be expected that there will be multiple representations of a piece of road or path. Where Type 3 and Type 4 USRN geometry exists, they will overlap Type 1 or Type 2 geometry. For example, Alan Drayton Way is represented by a Type 1 geometry (Alan Drayton Way) and a Type 3 geometry (B3037).

In England, overlapping USRN geometries may also occur where Highways England have an additional USRN allocated for the same street. This is due to Highways England being the responsible authority for trunk roads in England and they will therefore assign USRNs accordingly, whilst Local Highway Authorities will capture all the streets within their authority area, even if they are not responsible.

Additionally, multiple USRN geometries may exist for the same street where the Local Highway Authority boundaries are defined by the centreline of the street, where the geometry will be represented as overlapping.