Electoral statistics, UK: March 2020

• As of 2 March 2020, there were 47.6 million Parliamentary electoral registrations in the UK, the highest number ever recorded.

• The total number of UK Parliamentary electoral registrations increased by 484,000 (1.0%) between December 2019 and March 2020; this follows an increase of 1.3 million (2.8%) in the year to December 2019.

• The number of Parliamentary and local government electoral registrations increased in England, Wales and Scotland but decreased marginally in Northern Ireland.

• Electoral registrations increased in 379 of the 650 UK Parliamentary constituencies between December 2019 and March 2020, with the largest increases often in areas with large student populations.

• This publication of Electoral statistics has been produced to support the Parliamentary Constituency Boundary review due to finish in July 2023.

Statistician's comment

The number of parliamentary electoral registrations at 2 March 2020 was at the highest level ever recorded. This increase, compared to December 2019, reflects the full uplift due to the most recent General Election.

Neil Park, Centre for Ageing and Demography, Office for National Statistics

Follow the ONS Centre for Ageing and Demography on Twitter @RichPereira_ONS

The total number of UK Parliamentary electoral registrations in March 2020 was 47.6 million, the highest number on record, surpassing the previous highest number recorded in December 2019 (Figure 1). In the period between December 2019 and March 2020, the number of electoral registrations increased by 484,000 (1.0%). This follows an increase in the number of Parliamentary electoral registrations between December 2018 and December 2019 of 1.3 million (2.8%).

As reported in our previous release of Electoral statistics, these increases can be attributed to a combination of factors. These include increases in the number of people eligible to vote and the impact of a busy year (2019) of elections across the UK. The relationship between electoral registration data for December 2019, March 2020 and at the time of the December 2019 general election is described in section 3.

Change at Parliamentary constituency level

The number of electoral registrations increased in 379 (58%) of the 650 Parliamentary constituencies across the UK between December 2019 and March 2020. In the period between December 2018 and December 2019, the number of electoral registrations increased in 609 (94%) constituencies. Overall, between December 2018 and March 2020, the number of registrations increased in 98% (639) of constituencies.

Table 1 shows the Parliamentary constituencies that have seen the biggest percentage increases in electoral registrations between December 2019 and March 2020. Of the top 10 fastest increasing areas, eight are home to large populations of students and two are in central London areas with relatively young populations. The large increases in electoral registrations in these areas are almost certainly an indication of engagement with the 2019 general election and high levels of population churn (people moving into and out of the area on a regular basis) than large-scale population growth.

A common feature of areas with large populations of students is that they have a high level of population churn, as new cohorts of students arrive every year and graduates leave. In areas of central London, and other large cities, these is a similar pattern of large cohorts of young and mobile adults joining and leaving the population on a continuous basis.

The number of electoral registrations decreased in 11 Parliamentary constituencies between December 2018 and March 2020. These areas were spread across the UK with no geographic pattern. Many areas experiencing a decease in the number of electoral registrations had seen unusually large increases in electoral registrations in the year between December 2017 and December 2018. These include Scunthorpe, Waveney, Brigg and Goole, South Swindon, North Swindon and Carlisle. Between December 2017 and December 2018, the number of electoral registrations fell in nearly three quarters of Parliamentary constituencies.

The number of electoral registrations in the three Parliamentary constituencies in Stoke-on-Trent (Central, North and South) decreased in the period between December 2018 and March 2020 and also between December 2017 and December 2018. The decrease in electoral registrations throughout this period is unusual and might reflect a particularly high level of electoral registrations in December 2017.

The total number of Parliamentary electoral registrations reported in this release is very similar to comparable electoral registrations data relating to the 12 December 2019 general election (a difference of 9,400 electoral registrations (negative 0.02%)).

The electoral statistics for 2020 included in this bulletin relate to the number of people on the electoral register as at a reference date of 2 March 2020, around two and a half months after the December 2019 general election. However, the data in this release have a greater coherence to the electorate figures from the time of the general election than the 1 December 2019 Electoral statistics published in May 2020. This is because even though the 1 December 2019 reference date is closer to the December 2019 general election date, electoral registration officers (EROs) published their registers for 1 December 2019 at different times throughout the period between November 2019 and March 2020.

In the absence of an election, the range of publication dates by the EROs would have made little difference to the numbers reported. For example, the number of people on the electoral register at the start of December 2019 would generally not have changed much from the number in the first half of November 2019.

However, the data for those EROs who published their registers in November 2019 will not have included people who subsequently registered to vote in the general election held on 12 December 2019 (people had until 26 November 2019 to register to vote in the general election). Including these later vote registrations provided an uplift to the total number of UK Parliamentary electoral registrations across the UK, bringing the total on election day up to 47,567,800. This was 493,000 (1%) higher than the number of electoral registrations at 1 December 2019. This release of Electoral statistics for March 2020 reflects a similar pattern; electoral registrations in March 2020 were 1% (484,000) higher than at December 2019.

The coherence between the electoral statistics presented in this release and the number of electoral registrations at the time of the 2019 general election is very strong at the Parliamentary constituency level. Table 3 compares the difference between the number of electoral registrations at the time of the general election with the number of registrations as at December 2019 and March 2020. For 75% of Parliamentary constituencies, the difference between the number of electoral registrations at the general election and those in March 2020 was plus or minus 1% (94% of constituencies were within plus or minus 2%).

Annual canvass

By law the register of electors is checked each year by sending a household enquiry form to every household in the council area. This is known as the annual canvass. The purpose of the canvass is to identify everyone who should be on the electoral register. This means identifying citizens who should be registered but are currently not, as well as identifying electors who are no longer at a property and should therefore be removed from the register. A revised version of the electoral register must be published by 1 December, following the conclusion of the annual canvass.

Electoral register

The electoral register is a list of all people who are registered to vote in elections and referendums. The creation and maintenance of the electoral register is the responsibility of local electoral registration officers.

Electoral registrations

The number of registrations on the electoral register. It should be noted that individuals who have more than one address may register in more than one place and that not everyone eligible to vote is registered to vote. Additionally, not everyone usually resident in the UK is entitled to vote.

Parliamentary electors

The total number of Parliamentary electors consists of residential qualifiers, attainers and overseas electors. Further information on who can vote in different UK elections can be found on the GOV.UK website.

Local government electors

The total number of local government electors consists of residential qualifiers and attainers, including peers and European Union citizens. Local government areas are unitary authorities, London boroughs and district councils in England; unitary authorities in Wales and council areas in Scotland and Northern Ireland. Further information on who can vote in different UK elections can be found on the GOV.UK website.

Attainer

Attainer is the term used to describe a person who attains the age of 18 years during the normal currency of the register (after 1 December 2019 but before 1 December 2020), and is entitled to vote at an election held on or after his or her 18th birthday. As a result of the "Scottish Elections (Reduction of Voting Age) Bill", which was passed by the Scottish Parliament in 2015, 16- and 17-year-olds are now eligible to vote in local government elections in Scotland. Attainers are therefore those who will reach the age of 16 years during the currency of the register.

More quality and methodology information on strengths, limitations, appropriate uses, and how the data were created is available in the Electoral statistics QMI.

For England and Wales, electoral statistics are taken from data supplied to the Office for National Statistics by local electoral registration officers. Data for Scotland are similarly collected by National Records of Scotland (NRS). Data for Northern Ireland are collected by the Electoral Office for Northern Ireland (EONI). We collate these statistics for the UK using the data supplied by NRS and EONI. The RPF29 form that underpins this publication does not collect data on electoral registrations by age, sex, citizenship or any other characteristics.

There are at present 650 Westminster Parliamentary constituencies in the UK, made up of 533 in England, 59 in Scotland, 40 in Wales and 18 in Northern Ireland. These boundaries came into effect at the May 2010 general election. The typical size of constituencies differs between the constituent countries of the UK. It is possible in certain circumstances for someone to be lawfully registered to vote at more than one address. This could include, for example, students who have different home and term-time addresses.

Electoral statistics are available for the two main groups of voters:

• Parliamentary electors – those entitled to vote in Westminster Parliamentary elections

• local government electors – those entitled to vote in local government elections

The difference in who is entitled to vote at Parliamentary and local elections depends largely on residence and citizenship conditions. Local government electors, for example, include those European Union citizens resident in the UK who are not entitled to vote in Westminster Parliamentary elections, while Parliamentary electors include British citizens resident overseas who are not entitled to vote in local government elections.

The majority of those registered to vote in local government elections are also eligible to vote in European elections. To be entitled to vote in European elections in the UK, European Union (EU) citizens are required to request the right to vote in this country rather than their home country. Those persons who do not make this request will not be included in the European Parliament electorate.

The local government electorate in Scotland includes 16- and 17-year-olds who are ineligible to vote in European elections. Further information on who can vote in different UK elections can be found on the GOV.UK website.

There are three main reasons why the registered numbers of electors in an area can change from year to year:

• a change in the size of the population who are entitled to vote; for example, because of international migration, internal migration, deaths

• a change in the proportion of the eligible population who register to vote; for example, more people registering as a result of better canvassing or because of an election

• changes to the franchise in Scotland in the summer of 2015 to allow 16- and 17-year-olds to vote in Scottish Parliamentary elections and local government elections in Scotland

Publication of data for 2 March 2020

This collection of Electoral Statistics for 2 March 2020 has been published to support the 2021 Parliamentary Boundary Review. Ordinarily, the boundary review would have used statistics relating to the regular December reference date but in light of the coronavirus (COVID-19) pandemic, the Parliamentary Constituencies Bill has been amended to allow the independent boundary review to be based on verified versions of electoral registers from 2 March 2020 and not from 1 December 2020.

This will enable the four independent Boundary Commissions to use data for March 2020 from before government restrictions were put in place to tackle the pandemic. This removes any risk of using data potentially affected by the impacts of the coronavirus and ensuring the review is based on the most accurate reflection of the UK electorate available.

Electoral statistics usually refer to a 1 December reference date each year. Providing electoral statistics for this date allows for the completion of the annual canvass by electoral registration officers each autumn. The annual canvass helps to keep electoral registers as accurate and as complete as possible. In response to the coronavirus (COVID-19) pandemic, the UK government amended the final date for the 2020 registers to be published, extending it from 1 December 2020 to February 2021. This allows local authority staff more time to complete their canvassing and maintain the accuracy of their registers, in light of practical consequences such as redeployed resourcing and social distancing.

Quality

Electoral statistics represent the most accurate count possible of the number of people on electoral registers each year. They are subject to full quality assurance procedures, are reliable and provide comparable data across the UK constituent countries.

The electoral statistics we publish are used by Boundary Commissions, the Electoral Commission and central government to help with the improvement of electoral policies and for statutory reviews of Parliamentary constituency boundaries. The statistics are also of interest to Members of Parliament and the general public.

Comparing population estimates and electoral statistics

The electoral statistics in this bulletin give information on the number electoral registrations to vote in the UK. There is no similar collection of data on the number of people who are eligible to vote but who do not register.

We provide mid-year estimates of the resident population and these have sometimes been used as an estimate of the total number of people who are entitled to vote. However, care must be taken in using these data for that purpose as the population estimates include some people who are not eligible to vote and exclude some people who are eligible to vote (for example, overseas electors).

We have also published some research looking at the scope and quality of the electoral register as a likely source of data for measuring population, which is available in the Administrative Data Sources Report on the Electoral Register (PDF, 554KB).

The Electoral Commission continues to conduct research on voter registration, as well as providing information and guidance to both electoral registration officers and the general public. In July 2016, the Electoral Commission published a report into the accuracy and completeness of the December 2015 electoral registers.

Further information to support the electoral statistics, covering methodology, quality and data sources is available from us:

• the Office for National Statistics (ONS) revisions and corrections policy explains how we implement and categorise revisions to statistics

• get the latest news on our population statistics by subscribing to the quarterly newsletter (email your request to pop.info@ons.gov.uk) or by following the Twitter account @richpereira_ONS

Data collection issues for local authorities in England

The electoral registration officers (EROs) in each local authority in England would usually provide data to the ONS through a form (known as an RPF29) and their full register to the Boundary Commission for England (BCE). For the March 2020 data collection, there have been issues in producing the RPF29 data in four local authorities (Broadland, City of London, South Norfolk, Stevenage) and the data presented in this release have instead been derived by the BCE from the full electoral register; where this has happened, BCE have agreed these figures with the local authority.

For two other local authorities (Greenwich and Welwyn Hatfield), RPF29 forms were received but significant issues were identified when these were compared with the full electoral register held by the BCE; the data presented in this release reflect the full electoral register rather than the RPF29.

Data on anonymous electors, electors opted out of the open register and overseas electors have been published as part of the previous two Electoral statistics releases. For this release it is not possible to provide these tables as these data have not been supplied for all local authorities because of issues with the software used to generate RPF29 forms. However, it is intended that the regular release of electoral statistics for December 2020 (to be published in Spring 2021) will include these tables again.

To support the review of Parliamentary constituency boundaries, this release of Electoral statistics contains data on electoral registrations at ward level for the first time. Ward data are provided on existing ward boundaries where no changes are currently planned and on prospective boundaries where changes have been agreed, and data supplied to the ONS, even if the wards have not yet been fully implemented. Consequentially, for some wards we are not able to provide a 9-digit ward code. Further, we expect to update these data in early 2021 once EROs in other local authorities across England supply data on prospective wards.