This is the latest in an occasional series of blog posts about the campaign for open address data in the UK. Previous posts are listed at the bottom.
Background
Earlier this year, several members of the UK House of Lords sponsored an amendment to the Data Protection and Digital Information Bill that would have required the Government to regularly publish a list of UK addresses as open data to an approved data standard. The amendment and the Bill itself subsequently fell by the wayside, but the proposal was debated in the Lords in late March.
The UK Government has continued to dismiss this idea as impractical, relying mainly on arguments from Royal Mail and findings from rudimentary exploratory work carried out in 2016 towards an Open Address Register.
Currently, the most authoritative national address datasets are the Postcode Address File (PAF), maintained by Royal Mail, and Ordnance Survey's AddressBase. AddressBase includes data from PAF and from other sources such as property tax lists maintained by the Valuation Office Agency (VOA), but the primary underlying source for UK address records is the Local Land and Property Gazetteers maintained by local planning authorities. Data from these LLPGs is collected into a National Address Gazetteer by GeoPlace, which is co-owned by Ordnance Survey and the Improvement and Development Agency for Local Government (IDeA).
FOI request to Leeds City Council
None of the UK's authoritative national address data products are available as open data. But what about the underlying data held by local authorities?
A couple of weeks ago I sent an FOI request to Leeds City Council for an updated version of its list of Council Tax bands of all properties in Leeds.
This list was previously published on the Council's Data Mill North website annually from 2015 to 2018, for re-use under the terms of the Open Government Licence. The list is unusual because it contains addresses for most properties in the local area – essentially, all residential addresses along with the Council's reference number and the Council Tax band for the property. As far as I know, Leeds is the only UK local authority that has published its bulk address records as open data.
As there had been no update from Leeds since 2018, I anticipated there might be barriers to open release of fresh address data. But I was pleased to receive a response yesterday from the Council, notifying me that it had now published a 2024 version of the list.
From my perspective as an open data campaigner, this is an ideal outcome to my request – the Council has not only disclosed the requested information, and confirmed permission to re-use the information under the OGL, but has also made the information available on the public web.
(That said, FOI aficionados may raise an eyebrow at the Council's application of the S21 exemption, given that the information was not "reasonably accessible" to me at the time of my request.)
Geocoded version of Leeds address data
Unlike the earlier releases, the 2024 version of the Leeds dataset includes a UPRN (Unique Property Reference Number) for each property, in addition to the Council's own reference number. Ordnance Survey claims ownership of UPRNs, but since the introduction of OS's Open Identifiers policy in 2019 public authorities have been allowed to append the identifiers to their own open property data.
Inclusion of UPRNs makes it possible to match and add attributes from other open datasets to the Leeds dataset. In particular, we can append geographic coordinates and statistical codes from the ONS UPRN Directory (ONSUD).
I have created a geocoded version of the Leeds dataset that includes coordinates (BNG/OSGB26 easting and northing and WGS84 lat/lng) and also codes for the Census 2021 Output Area and local council area.
I could also have added postcodes from ONSUD, but have not done so as there is already a postcode field in the Leeds dataset.
You can download the geocoded dataset: LEEDS_CTBANDS_ONSUD_2024.zip (14.6 MB zipped). The download includes the data in CSV and GeoJSON formats.
Like the source data, this geocoded dataset is open data. Please see the ReadMe file for technical notes on data quality and attribution.
Why don't all local authorities publish their address data?
It seems to me that Leeds City Council's open publication of its Council Tax band list, with full address data for all residential properties, demonstrates that it should be feasible for other local authorities to do the same, and for Government to publish a national open address file from those sources.
As far as I can see, the Leeds data is essentially the same as the local authority address lists maintained by the Valuation Office Agency and tax agencies in other parts of the UK, e.g. the national dataset that underlies VOA's Check your Council Tax band service.
Data for non-residential properties is also maintained in local gazetteers, so there should not be any additional barriers to extracting and collating those address records.
Why don't other councils publish their address data, as Leeds has done? There are a couple of possible reasons I can think of.
Most local authorities in England publish a limited amount of open data, with a focus on their obligations under the Local Government Transparency Code. Leeds City Council is one of a relatively small number of local authorities that have taken a proactive approach to realising the potential for open data more broadly. It may be that other local authorities could publish their address data in the same way, but simply haven't the internal motivation to do so.
It may also be that Leeds is more confident than other authorities that it can lawfully publish its address data under an open licence, because it has a better understanding of the lineage of the data in its LLPG and/or has managed that data in a way that distinguishes the Council's own intellectual property from IP that might be subject to third party claims. Councils with less expertise in those areas are prey to external advice, from Ordnance Survey and other organisations with a motive to discourage open publication of address data.
Previous posts related to the campaign for open address data in the UK
Whatever happened to the UK Government's Open Address Register programme? (1 October 2024)
FOI release: Royal Mail's view on a House of Lords proposal for open address data in the UK (15 August 2024)
Open addresses in the House of Lords – what happened? (28 March 2024)
Thoughts on campaigning for open address data in the UK (30 June 2023)
UK address data: a primer and bibliography (last updated 30 November 2022)