Reviewed and updated: 17 October 2026. Original archive publication date retained.
A Unique Street Reference Number, usually shortened to USRN, is an identifier used to distinguish street records. It is particularly useful when names are duplicated, written differently or changed over time. A street reference and a postal address answer different questions.
Street and property identifiers
Ordnance Survey’s guidance distinguishes the USRN used for streets from the Unique Property Reference Number, or UPRN, used for addressable locations. A USRN should not therefore be treated as the identifier for one particular flat or house.
Street records support the consistent exchange of information between organisations. The identifier helps systems connect information even when the text used to describe a street is inconsistent.
Using the reference
When working with a dataset, read its definitions before joining records. Check whether the field is actually a USRN, a UPRN, a postcode or a local reference. Similar-looking codes are not necessarily equivalent.
For an operational enquiry, keep the street name and locality alongside the reference so that a person can check the intended location. If a record seems wrong, use the relevant street or address authority’s correction process.
A USRN does not by itself establish property ownership, a legal boundary or the extent of a right of way. Those questions need the appropriate records. It is a tool for identifying and connecting street information, not a substitute for title or highway evidence.