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National Address Gazetteer infrastructure


What is the role of custodians and SNN officers in the creation of the NAG infrastructure?

District and Unitary Authorities have a statutory responsibility to name streets and number properties. This street naming and numbering (SNN) information is combined with other information to produce the Local Land and Property Gazetteer (LLPG). The LLPG is the mechanism to electronically capture property addresses and streets in accordance to the BS7666 format.

Authority updates are supplied from the LLPG by address contributing authorities to GeoPlace on a regular basis. GeoPlace combined this local intelligence with other national data sources to produce the National Address Gazetteer infrastructure which in turn form the AddressBase range of products, made available through Ordnance Survey.

We manage the National Address Gazetteer infrastructure which is the data storage and set of processes bringing together the existing local authority sourced addressing datasets together with Ordnance Survey, Valuation Office Agency and Royal Mail data. Through agreement between Ordnance Survey and Scotland's Improvement Service, working on behalf of Scottish Local Government, the National Address Gazetteer includes Scottish address data.

Local authorities provide their address update records to us on a continuous basis for inclusion in the National Address Gazetteer infrastructure. The National Address Gazetteer infrastructure contains over 40 million addresses. In every six weekly cycle we synchronise 2,599,000 changes and carries out a total of 3,440 data validation checks.

From NAG to AddressBase

The National Address Gazetteer infrastructure is the single source from which AddressBase products are developed and made available by Ordnance Survey. 

AddressBase® Premium, available from Ordnance Survey, is the most comprehensive and accurate geographic dataset of 40 million addresses, properties and land areas where services are provided. 

Thanks to the relationship with local authorities, users of AddressBase benefit from the most in-depth view of addresses throughout the property lifecycle – from planning permission, through construction, occupation and change of use to demolition and beyond.