Electoral registration in Great Britain in 2021


About this report

This report looks at how the 2021 canvass in Great Britain was run and considers the ongoing impact on the electoral registers of the changes to the annual canvass process introduced in 2020.

The 2021 canvass was the second using the new processes introduced in 2020. These changes involve comparing the registers with other public data in order to give EROs information they can use to target their resources at households where residents’ details are most likely to have changed.

While we cannot yet draw conclusions on the impact of the new process on the accuracy and completeness of the registers, our analysis of available data suggests potential issues with the effectiveness of the reformed canvass in keeping pace with population movement:

  • The data matching process and/or the lag between matching and canvassing means some households are being allocated to the ‘wrong’ route – nearly a fifth of responses from households allocated to Route 1 (where no change in household composition was expected) reported significant changes to electors’ details. 
  • Necessary changes to electors’ details may not be reflected on the registers – 2.4 million households, one third of those allocated to Route 2 (where a change in household composition was expected), did not respond to the canvass. 
  • The reduction in the frequency of communication with Route 1 households may be contributing to the under-registration of attainers (those who will soon reach voting age) – the decline in the number of registered attainers, which began following the introduction of individual electoral registration (IER) in 2014, continued in 2021. The number of registered attainers dropped by 28.7% relative to 2020.

While we know that new registration applications are most readily driven by large scale electoral events, it is nevertheless important that the canvass and other year-round registration activity supports accurate and complete registers. This can help to reduce the large volumes of registration applications received immediately in advance of major polls, when Electoral Registration Officers’ (EROs) staff capacity is already stretched.

Our research studies into the accuracy and completeness of the registers are the definitive assessments of their overall quality. The next study, planned for the December 2022 registers, will allow us to fully assess the overall impact of the new canvass processes.

Over the next year we will continue to support and challenge EROs using the performance standards framework, and work with them to ensure we all make full use of the data that is available. This should help to provide a better understanding of the impact of particular practices within the current framework and support us with identifying and sharing good practice.

We also continue to recommend that the electoral registration system in Great Britain should be further modernised, to provide the best possible opportunity for ensuring that as many people as possible are correctly registered. This should include better use of public data, for example from other government services, to make registration easier for voters, and a more joined-up electoral registration system to reduce duplicate registrations and encourage registration all year round.  

Other register statistics

16 and 17 year olds (Scotland and Wales)

In Scotland and Wales, 16 and 17 year olds can vote in Scottish Parliament, Senedd and local council elections. This change was introduced in 2015 in Scotland and 2020 in Wales. 

Figures here relate to the annual registers published on conclusion of the 2021 canvass. The data does not, therefore, include those 16 and 17 year olds who may have registered to vote in the run up to the May 2022 local elections in Scotland and Wales. Data on the numbers of 16 and 17 year olds registered for the May 2022 elections will be published alongside the Commission’s reports on those polls. 

In Scotland, at the publication of the annual registers in 2021, 77,958 16 and 17 year olds were registered on the local government registers (see Table 4). This represents a 6.4% increase on 2020. Taken with ONS population estimates, this indicates that roughly two thirds of 16 and 17 year olds are on the local government registers in Scotland.1  

EROs across Scotland continued to engage with 16 and 17 year olds after publication of the revised registers to ensure they were registered ahead of the May 2022 polls. This work included undertaking engagement activities such as direct mailing, phone/text, contact with schools and universities, press releases, social media, newsletters and local advertising, as well as local activity with partner organisations. 

Table 4. Number of 16 and 17 year olds on the local government registers in Scotland 2015-21

Year 16 and 17 year olds
2015 48,962
2016 79,621
2017 83,536
2018 78,383
2019 73,777
2020 73,272
2021 77,958

In Wales, 33,241 16 and 17 year olds were on the local government registers on 1 December 2021 (a 115.1% increase on 2020). Comparison with the ONS population estimates suggests that just under half of 16 and 17 year olds in Wales are on the local government registers.2  

Across Wales, EROs carried out a range of activity to encourage registration amongst 16 and 17 year olds. Using grant funding from Welsh Government, many authorities appointed temporary public engagement officers and, in those areas, there appears to have been an increase in the range of engagement that was undertaken.  

In addition to more standard engagement activities such as direct mailing, phone/text, contact with schools, press releases, newsletters and social media, some authorities undertook additional activities such as: 

  • creating website banners and TikTok videos to share with schools
  • working with youth councils, youth partnership groups and Young Farmers Wales
  • sending 16th birthday cards
  • advertising in bus shelters
  • pop-up sessions in city centres
  • teacher training sessions using Electoral Commission resources

After the publication of the registers but ahead of the May 2022 polls, the majority of authorities sent out a household notification letter, with funding provided by Welsh Government, and many of these included extra information promoting the extension of the franchise and some also highlighted answers to FAQs.

Case study: Vale of Glamorgan Council - outreach with 16/17 year olds
The Vale’s Electoral Registration Public Awareness Officer delivered presentations to a school that held a Personal and Social Education day. Teaming up with a member of the council’s youth service, they produced a comprehensive package on registering to vote, how to vote and why we vote. The package also included information on elections and politics to try to demonstrate the importance of these to a young person. It covered a who’s who in politics and what politicians do, what elections they stand in and also how this links back to the things that young people might find important, so that they had a broader understanding of the whole voting process. A few simple tasks were set for them to do during the session to help keep them engaged. 

This outreach work helped to increase voter registration rates in the area amongst 14 and 15 year olds in the space of a year by 31.4% (1,263 to 1,660).

Overseas electors

A UK citizen living abroad who has been registered to vote in the UK in the past 15 years can apply to be an overseas voter. These registrations currently need to be renewed annually. The total number of overseas electors on the 2021 registers in Great Britain was 104,665.

Table 5. Number of overseas electors on the parliamentary registers in Great Britain 2015-21

Area 2015 2016 2017 2018 2019 2020 2021
England 97,572 241,097 205,687 113,833 185,513 170,196 94,908
Scotland 7,729 15,230 12,790 6,679 11,587 9,617 6,799
Wales 2,940 7,567 6,995 3,678 6,969 5,169 2,958
Great Britain 108,241 263,894 225,472 124,190 204,069 184,982 104,665

This is a decrease of 43.4% since the publication of the annual register in 2020. This decline is likely a consequence of the fact that there has not been an election in which overseas electors can vote since the 2019 UK Parliamentary general election.

The Elections Act 2022 extends the number of overseas citizens who will be eligible to register and vote, and also changes the requirement to renew registration annually to every three years. The extension of eligibility could result in a high volume of applications close to the next UK parliamentary general election, which EROs will need to be prepared to manage.

Anonymous electors

The number of anonymous electoral register entries on the parliamentary registers in Great Britain decreased from 3,374 in 2020 to 3,097 in 2021.

Anonymous registration is available for people meeting certain requirements, whose safety, or the safety of someone in the same household, is at risk. People registered anonymously appear on the electoral register without their name and address.

Table 6. Number of anonymous electors on the parliamentary registers in Great Britain 2015-21

Area 2015 2016 2017 2018 2019 2020 2021
England 2,151 2,194 2,440 2,550 3,214 3,064 2,788
Scotland 111 117 116 130 194 196 187
Wales 74 74 85 108 138 114 122
Great Britain 2,336 2,385 2,641 2,788 3,546 3,374 3,097


Variations in response rate

The Route 2 response rate continued to vary significantly in 2021 (see Table 9), as it had done in 2020. For the second year, Scotland reported the lowest response rate among Route 2 properties (50.7%) and England reported the highest (70.1%). 

Table 9. Response rate for Routes 1 and 2, by nation and English region 2021

Region Route 1 Route 2
England 19.0% 70.1%
North East 7.0% 62.7%
North West 15.3% 63.2%
Yorkshire and the Humber 14.0% 67.3%
East Midlands 18.8% 75.6%
West Midlands 17.8% 71.2%
East of England 19.9% 75.8%
London 20.4% 65.9%
South East 26.0% 74.2%
South West 22.6% 75.4%
Scotland 13.6% 50.7%
Wales 15.6% 65.4%
Great Britain 18.3% 68.1%


Major and minor changes per route

Major and minor changes per route

The nature of the responses received is also important. Responding households can record a major change (e.g. reporting that a potential new elector is resident), a minor change (e.g. amending the name of an existing elector) or no change (i.e. confirming the existing details of household members). Understanding the distribution of these changes can tell us about the accuracy of the data matching.

Of the 9 million responses received across all routes, 2.7 million households reported a major change (30.4%). Table 10 shows how these major changes were distributed across the three routes. The pattern is broadly in line with 2020. 

Table 10. Distribution of major changes across routes

  Number of major changes % of major changes across all routes
Route 1 830,743 30.4%
Route 2 1,856,309 67.8%
Route 3 49,339 1.8%
Total 2,736,391 100.0%

The highest proportion of major changes were reported by Route 2 households – i.e., those identified during the data matching step as the households most likely to report changes to residents’ registration details. However, as in 2020, nearly a third of the major changes reported relate to Route 1 households, where the DWP and/or local data had indicated no change was likely to be needed.

As in 2020, of all the households allocated to Route 1 (21.7 million) the proportion reporting a major change (830,743) is small (3.8%). However, as Figure 1 below shows, of those that did respond, a fifth reported a major change. Importantly for the quality of the registers, it is also unlikely that all of the Route 1 households that needed to report a major change have done so – particularly as they would have received limited contact from the ERO.

We do not have comparative data on the number of major changes reported by households during the canvasses preceding the reforms. It is therefore not clear to what extent the 2020 and 2021 canvasses are out of line with historic figures. However, it is clear that either the data matching process does not accurately identify all properties where changes will be needed and/or there is an impact from the lag time between the matching and the canvassing taking place.

Figure 1. Percentage of responding households in Routes 1 and 2 who reported major / minor / no change (data collected from 4/5 LAs where a revised data specification was implemented)1

Percentage of responding households in Routes 1 and 2 who reported major / minor / no change

As part of our work with EROs throughout the 2021 canvass, we have sought to understand the potential reasons for the proportion of changes reported for route 1 households. Many of those we spoke to highlighted potential reasons such as house moves within areas, marriages, attainers and deaths. It could also be a product of data accuracy, for example, with records used for matching not being up to date. We will continue to build on this over the 2022 canvass, to develop a deeper understanding of the data and how the process is working in practice.

Additions and deletions

Canvassing households does not directly result in new registrations. When a household reports that a potential new elector is resident, that individual still needs to submit an application to be added to the register. Where a household reports that electors need to be removed from the registers, a second piece of evidence (e.g. locally held data) would be needed before the ERO could confirm the deletion.

Entries need to be added to, and deleted from, the registers for several reasons including migration, home movement and deaths. The level of these additions and deletions provides insight into whether registration activity is keeping pace with population change. As population mobility varies across the country, so does the scale of the challenge faced by EROs. 

As in 2020, the distribution of additions and deletions across the routes is largely as expected, with Route 2 households accounting for the highest proportion of changes (see Table 11). However, as with the household major changes, more than a third of both additions and deletions came from households whose composition was assumed to be unchanged following the data matching. Again, this suggests either a degree of inaccuracy in the allocation of households to routes or an impact from population movement between matching and canvassing.  

Table 11. Percentage of additions and deletions per route 

  Route 1 Route 2 Route 3
Additions 37.1% 59.6% 3.4%
Deletions 39.4% 57.3% 3.3%

This data suggests that at least some population change is not being picked up by the registers. However we cannot draw clear conclusions on the overall impact – partly because of the variable impact of electoral events outside the canvass.

Table 12 below shows the levels of additions and deletions in recent years (for the full year, not just the canvass). Both 2020 and 2021 have recorded lower figures than many previous years. However, it is usual to see higher levels, of additions in particular, in years with significant UK-wide electoral events (such as UK general elections and the EU referendum). The lower figures in 2020 may relate directly to the effects of the pandemic – both on EROs’ ability to canvass and through depressing levels of population movement. 

Table 12. Percentage of additions and deletions 2010-21

Year Additions Deletions
2010 13% 12%
2013 15% 15%
2015 15% 15%
2016 15% 13%
2017 13% 13%
2018 11% 12%
2019 13% 10%
2020 10% 10%
2021 11% 11%

As Table 13 sets out, we also expect to see a higher proportion of changes being picked up during the canvass period, compared to the rest of the year, in years without UK-wide elections (e.g. 2018) – a trend that continues in 2020 and 2021.

Table 13. Percentage of additions during and outside of canvass period 2015-21



During canvass


Outside canvass


During Canvass


Outside canvass

2015 40% 60% 58% 43%
2016 38% 64% 54% 47%
2017 39% 61% 56% 44%
2018 68% 32% 68% 32%
2019 62% 38% 61% 39%
2020 56% 44% 64% 36%
2021 61% 39% 61% 39%

This point is also supported by the 2021 data on the proportion of additions and deletions recorded during the canvass period across the three nations of Great Britain (see Table 14). The proportion of additions and deletions during the canvass were lowest in Scotland (39.0% and 55.0%, respectively), followed by Wales and then by England. This is in line with the level of engagement at the May 2021 elections where turnout was highest in Scotland, then in Wales and lowest across England.

Table 14. Additions and deletions during full year and canvass period per nation



Full year


Canvass period


% during canvass 


Full year


Canvass period


% during canvass

England 4,308,807 2,777,863 64.5% 4,674,707 2,875,974 61.5%
Scotland 455,341 177,552 39.0% 415,722 228,843 55.0%
Wales 245,670 112,310 45.7%     232,649 137,629 59.2%
Great Britain 5,009,818 3,067,725 61.2% 5,323,078 3,242,446 60.9%

It is important that the canvass and other year-round registration activity continues to provide a high quality register at all times in order to avoid significant updates needing to be made in advance of major polls. We have previously highlighted our concern that the registration system, including the canvass, is unlikely to be sustainable in the longer term and have recommended that governments should explore more automated registration processes. For example, regular access to reliable data from a wider range of public services about people who have recently updated their address details would allow EROs to make contact directly with them at their new address to encourage them to register to vote. Integrating electoral registration applications into other public service transactions could also make it easier for individuals to keep their registration details up to date and accurate.

While canvass reform has addressed one aspect of sustainability – the resource and capacity taken up through unnecessarily chasing households where there has been no change – it is not yet clear what its impact is on the other key aspect – the system’s ability to pick up population changes away from major electoral events. Our next accuracy and completeness study will allow us to more clearly assess the overall impact on the registers, as it will take place after three years of the reformed canvass in Great Britain.


Electoral registers

There is no national electoral register for the United Kingdom. 368 separate electoral registers are compiled and maintained by Electoral Registration Officers (EROs) across Great Britain, and one register for Northern Ireland is compiled and maintained by the Chief Electoral Officer.

Electoral Registration Officers (EROs) are required to maintain two electoral registers:

  • Parliamentary register – used for UK Parliamentary elections
  • Local government register – used for Scottish Parliamentary, Senedd, Northern Ireland Assembly, local government and Police and Crime Commissioner elections

The electoral register is a property based database, with register entries linked to a property. This means that the quality of its information is affected by ongoing population change and EROs need to add and delete records for home-movers, electors who have died and newly eligible electors.

New registers are published annually and reviewed most months. In Great Britain, there is a process of auditing the register annually before a revised version is published, which is known as the annual canvass. Each ERO is required by law to conduct an annual canvass of all properties in their area to confirm their electoral register entries and to identify electors who have moved or were not previously registered.

The reformed canvass

The 2021 canvass was the second to take place under a new model which incorporates data matching between the electoral registers and a combination of national and local data at the outset of the process. This data matching informs the ERO which properties are likely to have an unchanged household composition to enable them to target their canvass activity accordingly.

The ERO will then follow one of three routes for each property:

  • Route 1: Properties are placed into Route 1 if the entries of registered electors match with other data, such as that held by the DWP, and the composition of the household is therefore assumed to be unchanged. The ERO will contact Route 1 households to invite them to provide information on any changes which have occurred. Where there are no changes to report, the household is not required to respond.
  • Route 2: Properties are placed into Route 2 if any of the entries of registered electors do not match with other data, such as that held by the DWP, and the composition of the household is therefore assumed to have changed such that the electoral register needs to be updated. These households are required to respond to requests for information regardless of whether or not they do in fact need to report a change.
  • Route 3: This route is available for those properties where the ERO thinks they can most effectively and efficiently obtain information on residents through a ‘single responsible person’ acting on behalf of all residents. Care homes and student halls of residence are examples of typical Route 3 properties. Should the ERO be unable to successfully obtain information about the property from the ‘single responsible person’, the property is placed into Route 2.

Engagement with EROs

The Commission has the statutory power to set and monitor performance standards for EROs in Great Britain and has been doing so since 2008. In January 2020 we began a consultation on a new set of standards for EROs. However, as a consequence of the coronavirus pandemic, we deferred finalising the standards before the 2020 canvass. We did, however, make the draft standards and accompanying tools available to EROs, and these formed a key part of our guidance, support and challenge package relating to the delivery of the first reformed canvass in Great Britain. The new standards were then finalised and laid before the UK, Scottish and Welsh Parliaments in June 2021.

Over 2020 and 2021 we have used the standards to inform our engagement with EROs about electoral registration, and to support and challenge them in their work to maintain the electoral registers in their area. We have placed a significant focus in our engagement with EROs on supporting them to develop relevant and appropriate KPIs, helping them establish a baseline of their own performance and set targets which take into account their own specific circumstances, and supporting them with using available data to identify areas where improvements may be made. Now that the standards have been in operation for two years, we can use the data and information gathered to identify potential patterns that are emerging. We will continue to use the performance standards framework over the course of this year to build on the work we have carried out with EROs in 2021, continuing to support them to better understand and report on the impact of their activity using the data available to them.

In particular we have identified areas of practice and key pieces of data that we want to focus on in our engagement with EROs during the 2022 canvass – for example, where there are a high number of major changes reported from properties allocated to Route 1 and non-responses from households in Route 2. The data we have gathered to date will help to inform and shape that engagement with individual EROs, with the aim of developing a deeper understanding of the impact of particular practices and approaches, which in turn can help us to identify and share examples of good practice.  

Download the electoral registration data 2021

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First published: 16 May 2022

Last updated: