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.
Open Identifiers product family
Easily combine data from different sources through OS Open Identifier products to help understand the geographical context of your 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.
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 UPRN
|OS Open USRN
|OS Open TOID
|OS Open Linked Identifiers
|Unique property references
|Unique street references
|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
Support and getting started
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With over 20,000 updates to our databases every day, you have access to a comprehensive and up-to-date set of authoritative data through the OS Data Hub.