Open Identifiers product family

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

Identifiers linking data

Linking data together

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 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's easy to use and share 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. It is critical for property related information and can be found throughout OS's AddressBase products. UPRNs provide a consistent, persistent identifier for buildings or objects.

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 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 OS’s large scale products. The TOID is based on the Digital National Framework concept and the principles that underpin it.

Comparison of Open Identifiers

This comparison table highlights the similarities and differences between the Identifier products

 OS Open UPRNOS Open USRNOS Open TOIDOS Open Linked Identifiers
Unique property references

Unique street references

Topographic identifiers

Relationships between UPRNs, USRNs and TOIDs

UPRNs for all addressable locations

USRN identifier and street type

Reference between a feature and qualitative data

1:1250 to 1:10,000 scale

Great Britain coverage

The OS Open Identifiers data products

  • OS Open UPRN

    An open dataset enabling linking, sharing and visualisation of data related to UPRNs.

  • OS Open USRN

    An open dataset containing all USRNs from OS MasterMap Highways Network with a simplified line geometry.

  • OS Open TOID

    A dataset of unique identifiers for a wide range of land-scape and built environment features with a generalised location from OS MasterMap products.

  • OS Open Linked Identifiers

    An open dataset of cross-referenced identifiers between various OS data products.

See how others are using OS Identifier data

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Support and getting started

Open data support

Open data support

Read technical specifications, getting started guides and supporting information on our OS open data products.

Open data support
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