UK address data: a primer and bibliography (updated)

The UK open data community has been calling for open address data for many years. We've made some progress around the edges on postcodes and statistical lookups, with occasional indications of support from government – but delivery of a fully open national address dataset has remained out of reach.

This post contains notes on the current availability of authoritative address data for the UK and provides a bibliography of reports and other resources that may be useful in understanding the potential benefits of unlocking address data as digital infrastructure.

Who owns UK address data?

The UK's address data infrastructure is managed centrally by GeoPlace, a Limited Liability Partnership jointly owned by Ordnance Survey and the Local Government Association (LGA).

GeoPlace maintains the National Address Gazetteer (NAG) which combines address data from the hundreds of Local Land and Property Gazetteers (LLPGs) held by planning authorities in England and Wales with additional data from Ordnance Survey, Valuation Office Agency and Royal Mail. The NAG also contains Scottish address data from the One Scotland Gazetteer maintained by the Improvement Service.

GeoPlace also maintains a data hub that contains address and street data from these and other sources including Northern Ireland, Isle of Man and Channel Island governments.

Ownership of UK address data is complex and any national address dataset is likely to contain intellectual property from multiple sources. Individual addresses are created by developers and planning authorities and compiled into datasets at local and national levels.

The postcode system is managed by Royal Mail. Local authorities assign an identifier called the Unique Property Reference Number (UPRN) to each new address, from blocks of UPRNs allocated by GeoPlace. Address-level geocodes are appended by Ordnance Survey and in Northern Ireland by Land & Property Services (LPS).

Most IP rights in the UK's address data infrastructure are owned by public bodies. However Royal Mail was privatised in 2013.

Address data products

Royal Mail's Postcode Address File (PAF) is the most widely used UK address dataset. PAF contains full addresses and postcodes for postal delivery addresses, but does not include UPRNs or geocodes.

PAF is licensed for re-use on a commercial basis through Royal Mail's Address Management Unit (AMU). The AMU also offers some associated products, including data on properties that have not yet been built.

PAF is governed by a Code of Practice agreed between Royal Mail and Ofcom in 2010.

The PAF Advisory Board provides independent advice to the AMU on behalf of PAF users. The Board's papers are a useful source of information about the business development of PAF.

AddressBase is an Ordnance Survey product that combines PAF with UPRNs and geocodes. There are enhanced versions of AddressBase that include properties without postal addresses, land areas, and cross-referencing to other datasets, as well as a separate product with data for Northern Ireland, the Isle of Man and the Channel Islands.

All of the above address data products are available on commercial terms through value-added resellers (VARs) as well as directly from the product owners. Some VARs provide specialised address management software.

PAF data is publicly available for re-use for specific purposes – not as open data – in a small number of third-party data products, such as Land Registry's Price Paid Data and MHCLG's Energy Performance of Buildings data.

There are also some free public data products that contain large amounts of address data apparently not derived from PAF; for example, Companies House's Free Company Data Product and the Food Standards Agency's food hygiene rating data.

AddressBase is the successor to other Ordnance Survey geocoded address data products: ADDRESS-POINT, Address Layer and Address Layer 2. Those products were withdrawn in 2014.

Ordnance Survey's Code-Point Open product contains postcode centroids for Britain derived from address-level geocodes. The non-open Code-Point with polygons product contains notional postcode boundaries also derived from address-level geocodes.

The Central Postcode Directory (CPD) maintained by NISRA contains postcodes with centroid geocodes for Northern Ireland, but is not available as open data.

National datasets of postcodes with centroid geocodes are also available as open data (except for Northern Ireland) in ONS's National Statistics Postcode Lookup (NSPL), ONS Postcode Directory (ONSPD), and NHS Postcode Directory (NHSPD).

Free address lookups

Royal Mail operates a Postcode/Address Finder service that provides free online lookups based on PAF data. GeoPlace operates a FindMyAddress service that provides free online lookups of addresses and UPRNs based on AddressBase data.

Both services permit a limited number of lookups per day and use of the results is restricted by terms and conditions.

Open data release of UPRNs

From July 2020, UPRNs and their associated geometry (point coordinates) have been available for re-use as open data under Ordnance Survey's Open Identifiers policy. The main data product is OS Open UPRN.

National datasets of UPRNs matched to postcode units and statistical geographies are available as open data in ONS's National Statistics Address Lookup (NSUL) and ONS UPRN Directory (ONSUD). From late 2020 those datasets also associate UPRNs with postcodes, enabling the calculation of notional geographic extents for individual postcode units.

The Cabinet Office's Open Standards Board has endorsed the UPRN as a standard for use by government organisations. That decision is contentious, as neither the addressing information represented by the UPRN nor associated metadata – for example, on parent/child relations and whether a UPRN is current or historical – are available for open re-use. The UPRN is conformant to British Standard 7666, which is also not open.

Other initiatives to compile national address data

The National Census Enumeration Address Register (NAR) created by Ordnance Survey, Royal Mail and the Local Government Information House for ONS's 2011 Census was apparently not re-used for further purposes. ONS has used AddressBase Premium as the main basis of its address frame for the 2021 Census.

Open Addresses UK, an ODI-affilliated project to crowdsource an open national address dataset, went into "hibernation" in 2015.

In the 2016 Budget the Government announced "£5 million to develop options for an authoritative address register that is open and freely available". It is unclear how or if that money was spent. An incipient GDS attempt to build an address register was abandoned in 2017.

In June 2021 OSMUK announced a project to accelerate mapping of addresses in OpenStreetMap.

Public sector access to address data

Most public authorities have free access to PAF, AddressBase and Pointer for internal use under centrally agreed licensing arrangements: the Public Sector Geospatial Agreement (PSGA), the Northern Ireland Mapping Agreement (NIMA), and the PAF Public Sector Licence.

The PSGA arrangements are administered by Ordnance Survey and funded through the Geospatial Commission, part of the Cabinet Office.

Bibiliography

The National Address Gazetteer: being run in the interests of Ordnance Survey, to the detriment of citizens and the private sector
Demographics User Group (DUG) letter to Francis Maude, January 2012

Addressing the world – An address for everyone
Universal Postal Union white paper, 2012

'Address Wars' and related commentary

Address wars – an armistice?
Cllr Bob Barr, October 2010

Is authoritative data worth the price? The case of addressing data in the UK
Slides from a talk by Prof Robert Barr, October 2013

Address Day: what next after the address wars?
Slides from a talk by Jeni Tennison, March 2015

Open addresses: will the address wars ever end?
Notes for a talk by Peter K. Wells, August 2016

An opportunity to improve the UK's most problematic public dataset: street addresses
Centre for Public Data (CFPD), January 2021

Unlike other countries the UK is not addressing a vital part of its future
post by Peter K. Wells, April 2021

This one weird trick could fix the British economy
post by James O'Malley, November 2022

Reports and consultations

OFT closed case: Ordnance Survey / National Address Gazetteer
Office of Fair Trading, February 2011

Estimating the Economic Value of PAF
PAF Advisory Board, September 2012

Postcode Address File Review including responses
Ofcom, 2013

An open national address gazetteer (the 'Neffendorf Report')
Katalysis Ltd report for BIS, January 2014

Open Data User Group (2012-14)

The case for an Open National Address Dataset + Annexes
Open Data User Group (ODUG), November 2012

The Postcode Address File (PAF) and International Examples
Open Data User Group (ODUG), January 2013

Further Benefits of an Open National Address Dataset
Open Data User Group (ODUG), February 2013

Submission to Royal Mail Postcode Address File (PAF) Licensing Consultation
Open Data User Group (ODUG), September 2013

The Case for an Open National Address Dataset: Update for MRS CGG
Open Data User Group (ODUG), November 2014 (via MRS)

Open Addresses UK (2014-15)

Open Addresses UK Transparency Board Proposal
Discovery Phase discussion document, 2014

Open Addresses: the story so far
Open Data Institute, May 2015

Hibernation (or a time for going to bed)
Open Addresses UK, July 2015

Pre-2010

Project Acacia
Acacia partnership via Land Registry, 2002-04

Postcode Address File - review of the management of PAF
Postcomm, 2004-07

Towards the National Spatial Address Infrastructure - Outline Prospectus
DCLG, 2005

Evaluating the benefits of the Local and National Land & Property Gazetteers
CEBR, 2006

A costly 2008 Domesday Book
Michael Cross of the Free Our Data campaign, April 2008

Edits: OfT report from 2011 added to bibliography on 23 June 2021. DCLG prospectus from 2005 added to bibliography on 3 July 2021. CBER report from 2006 added to bibliography on 4 July 2021. Link to post by James O'Malley added to bibliography on 30 November 2022.