You should consider AddressBase your source of truth for all address data in Great Britain, and use AddressBase Core whenever possible before other solutions. Use AddressBase Core to identify property and street information This is a free set of products that lets public sector workers access essential geospatial data as part of the Public Sector Geospatial Agreement (PSGA). The guidance shares best practice in accessing address data using Ordnance Survey (OS) AddressBase products. Every addressable location in Great Britain (England, Scotland and Wales and excluding Northern Ireland) has a UPRN, and using this standard can save money, time, resources and lives. This allows users to easily cross-reference between different data sets and reduces errors in data exchange and communication. You must use the Unique Property Reference Number (UPRN) standard when identifying places in the UK. Follow this guidance if you work in the public sector and you need to use address data, such as property and street information.

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