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Open Identifiers Family

Easily combine data from different sources through OS Open Identifier products to help understand the geographical context of your data.

Unique Identifiers are at the heart of how data can be effectively published, retrieved, reused and linked.  They are an essential component of data principles.

In the same way individual people have National Insurance numbers, key location identifiers are used to identify unique physical locations in Great Britain. 

As a simple code made of numbers and/or letters, it is easy to share and use Identifiers in any kind of dataset.

What are the OS Identifiers?

Unique Property Reference Number (UPRN)

A UPRN is a unique numeric identifier for every addressable location in Great Britain. The identifier is critical for property related information and can be found throughout OS's AddressBase products. An addressable location may be any kind of building, residential or commercial, or it may be an object that might not have a ‘normal’ address – such as a bus shelter or an electricity substation. UPRNs provide these addressable locations with a consistent, persistent identifier never being reused.

Unique Street Reference Number (USRN)

A USRN is a unique and persistent identifier for every street, road, track, path, cycletrack or way in Great Britain. It can be found in the OS MasterMap Highways Network products and is also a key component in OS’s AddressBase suite of products.

Topographic Identifier (TOID)

A TOID is a unique identifier, consisting of the letters ‘osgb’ and followed by up to sixteen digits, associated with every feature in many of Ordnance Survey’s large scale products. The TOID is based upon the Digital National Framework concept and the principles that underpinned it.

These identifiers contain no attribution or information, for example coordinate position.

To facilitate better linking, analysis and visualisation of these key location identifiers, we offer a family of Open Identifier products for you to download and freely use under Open Government Licence.


Introducing the OS Open Identifiers products


A dataset containing all UPRNs and geometry from AddressBase Premium. This will include UPRNs for features such as residential and commercial dwellings, ponds, electricity substations and advertising hoardings. It will be synchronised with AddressBase Premium in completeness and currency. 


A dataset containing all USRNs from OS MasterMap Highways Network with a simplified line geometry. It will be synchronised with OS MasterMap Highways Network in completeness and currency.


A dataset containing a generalised location for a wide range of features such as buildings without an address, road junctions, land cover and more. These are extracted from OS MasterMap premium products.

OS Open Linked Identifiers

A dataset containing the relationship between UPRNs, USRNs and TOIDs. The relationships are extracted from AddressBase Premium and OS MasterMap Highways Networks products.

Using the OS Open Identifier products


Get information on how to use these products to start easily sharing information you have associated to identifiers with a geographic location.

Access through API’s

The relationships between the Open Identifiers can be accessed directly via the OS Linked Identifiers API and is available for free under the OpenData Plan.

Identifiers, the key to unlock your data

Identifiers within our geospatial data act as a ‘golden thread’ across a diverse range of use cases. This could be identifying the correct location to deliver parcels, to ensuring the appropriate emergency response vehicle is deployed to an incident and to ensuring the correct road is being dug up to maintain underground assets.

Making the most of identifiers


See how adding the UPRN to other datasets can help make deeper sense of data once it’s all linked together.

Best practice guide (PDF)

Practical guidance on how identifiers can be designed, created and managed to make it easy for users to understand and combine data from different sources.

Open Identifiers policy

Our Open ID policy enables and encourages the use of our identifiers to join datasets and combine the value of our data with the value of yours.

Helping Britain’s recovery

When data is easily accessible and shared it leads to sound policy decisions and innovations in the economy.