Electoral registration statistics - WMCA Constituency

This dataset presents the number of people registered to vote across Westminster Parliamentary constituencies within the West Midlands Combined Authority (WMCA) area, as recorded on 1 December 2025. It is produced by the Office for National Statistics (ONS) as part of their annual Electoral Registration Statistics series, and has been filtered to cover the constituencies falling within the WMCA boundary. ## What is Electoral Registration? Electoral registration is the process by which eligible residents add their name to an electoral register, maintained by their local authority, in order to be entitled to vote in elections. Registration is a prerequisite for voting; simply being eligible to vote does not mean a person is automatically registered. Not all residents will be registered, and not all registered people will necessarily be resident at that address at the time of an election, which means electoral registration figures will differ from population estimates. An attainer is a person who is not yet old enough to vote at the time the register is compiled, but who will reach voting age (18 in UK Parliamentary elections) before the register expires. Attainers are included in the total registration count and are shown separately in this dataset. They represent young people, typically 16 or 17 years old, who have pre-registered so they are automatically added to the register when they turn 18. ## What the Dataset Contains The dataset contains one record per Westminster Parliamentary constituency within the WMCA area. For each constituency it provides the ONS area code, the constituency name, whether it is classified as a Borough or County constituency, the total number of electoral registrations, and the number of those registrations that are attainers. Note that this edition does not include a comparison column for the previous year (December 2023). This is because the current set of constituencies was introduced for the July 2024 General Election and did not exist in the same form previously, making direct comparison inappropriate. ## Geography The statistics cover Westminster Parliamentary constituencies whose boundaries fall within or overlap the West Midlands Combined Authority area. The WMCA comprises seven metropolitan borough councils: Birmingham, Coventry, Dudley, Sandwell, Solihull, Walsall, and Wolverhampton. The current constituency boundaries were introduced for the General Election of July 2024 and differ from those used in earlier editions of this dataset. Each constituency is accompanied by its standard ONS 9-digit area code and a classification of Borough (B) or County (C), which affects certain aspects of the election process. A lookup between previous and current constituency boundaries is available via the ONS Open Geography Portal. ## Methods Responsibility for compiling electoral registers lies with individual local authorities (LAs). ONS collects counts of registered electors as at 1 December from each LA's Electoral Registration Officer (ERO), quality assures the data, and publishes UK-wide statistics. The WMCA subset presented here has been extracted from that national dataset. Where an LA has not supplied data in time, ONS substitutes data from the previous available year or from data held by the relevant boundary commission. For the December 2025 edition, all local authorities supplied data. ## Caveats * Local authority data not included: This edition exceptionally does not include the usual local authority-level statistics. This is because software systems used by LAs to submit data had not all been updated to reflect recent legislative changes affecting who is eligible to vote in local elections (including changes to the franchise in Wales in 2021 and England in 2024). Rather than publish partial or inaccurate LA figures, ONS agreed with key data users to publish constituency-level data only. LA statistics are expected to be reinstated in the December 2026 edition. * Constituency boundaries and WMCA boundaries do not perfectly align: Some Westminster Parliamentary constituencies straddle the WMCA boundary, meaning a constituency may include residents from both within and outside the WMCA area. Registration counts reflect the whole constituency, not just the WMCA portion. * Not a population estimate: Electoral registration figures should not be used as a proxy for the resident population of an area. Many residents will not be registered, some registrations will relate to people who have moved away but not yet been removed from the register, and some deceased individuals may remain on the register for a period after death. * Double-counting: Because of the time taken to update registers, some individuals may appear on more than one area's register if they have recently moved, causing a small degree of double-counting in aggregate figures. * Eligibility varies by election type: The eligibility rules for UK Parliamentary elections differ from those for local elections. This dataset relates only to those registered for Parliamentary elections. ## Uses These statistics can be used to understand patterns of democratic participation across the West Midlands, support local policy and planning, and inform work on electoral engagement. The original national dataset is primarily used by boundary commissions, the Electoral Commission, and central government to inform electoral policy and statutory reviews of constituency boundaries. It is also used by MPs and the general public for research and analysis.