Electoral statistics, UK: 2015

The total number of UK parliamentary electors in 2015 was 44,722,000, a fall of 1.3% from 2014.

The total number of UK local government electors in 2015 was 46,204,700, a fall of 1.3% from 2014.

Between 2014 and 2015, the total number of both parliamentary and local government electors fell in England, Wales and Scotland, but increased in Northern Ireland.

The number of parliamentary electors fell in all regions of England between 2014 and 2015. The largest decrease (-1.6%) was in the West Midlands, the smallest in the East Midlands (-0.1%).

Between 2014 and 2015, the number of local government electors fell in all regions of England, apart from the East Midlands which saw an increase of 0.02%. The largest decreases were in London and the South East, both of which decreased by 1.6%.

The 2015 electoral statistics represent the first full registers following completion of the transition to Individual Electoral Registration (IER) introduced in England, Wales and Scotland in 2014.

Electoral statistics 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.

Electoral statistics are collated by the Office for National Statistics (ONS) and published for the UK and its constituent countries, local government areas and parliamentary constituencies. They provide annual counts of the number of people who are on the electoral registers, usually at 1 December each year.

References in this release to electoral statistics for 2015 should be taken to mean electors included on the registers published on 1 December 2015 in England, Wales, Scotland and Northern Ireland. Individual Electoral Registration (IER) was introduced in England and Wales in June 2014 and in Scotland in September 2014. (The transition to IER in Scotland was delayed in order to begin after the Scottish Independence Referendum).

See background note 5 for further details on comparing electoral statistics for different years.

Electoral statistics are available for the 2 main groups of voters:

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

• local government electors – those entitled to vote in local government and/or European elections¹

The difference in who is entitled to vote at parliamentary and/or local elections largely depends 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, whilst parliamentary electors include British citizens resident overseas who are not entitled to vote in local government elections. Further information on the eligibility criteria can be found in a Quality and Methodology Information paper from our Quality Reports for Government Statistics page.

There are 3 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, due to international migration

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

• 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

In particular the introduction of Individual Electoral Registration (IER) in 2014 has introduced new administrative practices. Although IER does not change who is eligible to vote, it may have changed the proportion of those eligible that are registered to vote. More information on IER is available in the section on related information.

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

• the UK electoral statistics Quality and Methodology Information (202.3 Kb Pdf) details a range of information about the background, quality, methods and quality assurance of the electoral statistics; this includes additional information on concepts, strengths and limitations, user needs and links to further advice about the output

• the ONS Revisions Policy explains how we implement and categorise revisions to statistics

• the transfer of the production of electoral statistics to the Electoral Commission is being considered by the Electoral Commission and ourselves - your views on this potential transfer are welcome; please contact pop.info@ons.gov.uk

• news on our population statistics can be obtained by subscribing to the quarterly newsletter (email your request to population.statistics@ons.gov.uk) or following the Twitter account @paulvickers_ONS

Methods, quality and uses

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 electoral statistics published by ONS 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.

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 and are reliable and provide comparable data across the UK constituent countries. Information on the quality of these statistics is provided in the Quality and Methodology Information report (202.3 Kb Pdf).

Notes for introduction

1. 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 electoral registers published in December 2015 represent the first full registers following completion of the transition to the new system of Individual Electoral Registration (IER) introduced in 2014.

The total number of UK parliamentary electors in 2015 was 44,722,000, a fall of 1.3% from 2014.

The total number of parliamentary electors in each of the UK constituent countries and the percentage changes between 2014 and 2015 are:

• England – 37,399,900, a fall of 1.1%

• Wales – 2,181,800, a fall of 2.0%

• Scotland – 3,896,900, a fall of 3.4%

• Northern Ireland – 1,243,400, a rise of 0.9%

Figure 1 shows the different patterns of change in parliamentary electors between the UK constituent countries over the last 5 years.

Between 2010 and 2012, the number of electors increased in all 4 countries, although growth was highest in Northern Ireland. Between 2012 and 2013, small decreases (of less than 1.0%) were recorded in all areas except Scotland. Between 2013 and 2014, there were larger percentage losses for England and for Wales.

England and Wales continued to see a fall in the number of parliamentary electors between 2014 and 2015, while over the same period in Northern Ireland the number of electors increased by 0.9%. In 2015, there were 1.1% fewer people registered to vote in parliamentary elections in England and 2.0% fewer in Wales than in the previous year. Between 2014 and 2015, Scotland saw a decline in its number of registered parliamentary electors; a fall of 3.4%.

In nearly all regions of England the percentage changes in the number of parliamentary electors between 2014 and 2015 were smaller than the percentage changes seen between 2013 and 2014; the exception being the West Midlands (Figure 2). Between 2014 and 2015, percentage falls were smallest in the East Midlands at 0.1% and largest in the West Midlands at 1.6%.

Parliamentary constituencies

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. This release provides counts of the total number of parliamentary electors for all parliamentary constituencies in the UK.

The typical size of constituencies differs between the constituent countries of the UK. In 2015, the median total parliamentary electorate across constituencies was about 54,300 in Wales, 66,700 in Scotland, 68,200 in Northern Ireland and 70,100 in England.

In 2015, the parliamentary constituency with the smallest sized electorate at 20,900 was Na h-Eileanan an Iar and the largest electorate at 105,400 was the Isle of Wight. These unusual electoral sizes are explained by these areas being island constituencies.

The total parliamentary electorate grew in 198 constituencies (30%) between 2014 and 2015, compared with 150 constituencies (23%) between 2013 and 2014. This increase may reflect an increase in registration before the General Election in May 2015.

In total in 2014 to 2015, 91 constituencies had growth of more than 1.0% in their parliamentary electorate including 19 which grew by more than 3.0%.

All of the constituencies, with the greatest percentage growth in parliamentary electors between 2014 and 2015, are in England. In Table 1, there are 7 areas that are borough constituencies, (which are mainly urban areas) and 3 that are county constituencies (which are partly or mostly rural). The labelling of a constituency as borough or county is made by the relevant Boundary Commission.

In Table 1, the list of constituencies includes 4 areas that saw large percentage falls in parliamentary electors in the previous year (Nottingham South, Loughborough, York Central and Liverpool Riverside). The turnaround for these constituencies may link to changes in population size or the population entitled to vote, or administrative differences in how the register was put together between the years.

In Wales, 4 of the 40 parliamentary constituencies showed an increase in the number of electors between 2014 and 2015. The Welsh constituency of Yns Môn (ranked 25th in the UK) recorded the greatest rise, with a growth of 2.7%, whereas in Northern Ireland the greatest growth was seen in the constituency of Lagan Valley (ranked 52nd in the UK with 1.7%). In Scotland the only constituency which saw a rise in the number of parliamentary electors was Falkirk (ranked 128th in the UK) with a percentage rise of 0.6% since 2014.

The total parliamentary electorate fell in 452 constituencies (70%) between 2014 and 2015. However, 37 constituencies had a fall of more than 5.0% in their parliamentary electorate including 3 which fell by more than 10.0%.

Table 2 shows that the 10 constituencies with the greatest percentage fall in parliamentary electors between 2014 and 2015 include 8 located in England. Half of these constituencies are classified as borough (or mainly urban) constituencies, the other half as county (or mainly rural) constituencies.

The remaining two constituencies in Table 2, Glasgow North East and North East Fife, are in Scotland. In Scotland, 98% of constituencies (58 areas) and in Wales 90% of constituencies (36 areas), had a smaller parliamentary electorate in 2015 than in the previous year. This is in contrast to Northern Ireland where no constituencies recorded a fall in the number of parliamentary electors between 2014 and 2015.

The electoral registers published in December 2015 represent the first full registers following completion of the transition to the new system of Individual Electoral Registration (IER) introduced in 2014.

The total number of UK local government electors in 2015 was 46,204,700, a fall of 1.3% from 2014.

The total number of local government electors in each of the UK constituent countries and the percentage changes between 2014 and 2015 are:

• England – 38,696,100, a fall of 1.2%

• Wales – 2,208,000, a fall of 2.1%

• Scotland – 4,030,000, a fall of 2.5%

• Northern Ireland – 1,270,700, a rise of 1.1%

Figure 3 shows the different patterns of change in local government electors between England, Wales, Scotland and Northern Ireland over the last 5 years. Overall, the pattern of change is very similar to that for parliamentary electors shown in Figure 1.

Over the last 5 years, the number of local government electors in England has fallen by an average of 0.4% each year, with growth in the years 2011 and 2012 offset by the falls from 2013 onwards. In particular, the number of local government electors in England fell by approximately 488,900 between 2014 and 2015.

The pattern for Wales is similar to that of England. In Scotland, there were increases in the local government electorate between 2010 and 2014 followed by a decrease of 2.5% between 2014 and 2015. A factor in the change in size of the electorate in Scotland is the introduction of a voting age of 16 and over for local government and Scottish Parliament elections. Owing to the timing of the decision to allow this, registration of these young voters during the annual canvass was relatively low, but it is likely that many more 16 and 17 year old voters will be added in advance of the Scottish Parliamentary election in May 2016.

In Northern Ireland, there has been a percentage increase in the size of the local government electorate in 4 out of the last 5 years, the exception being between 2012 and 2013.

Figure 4 shows the percentage change in the number of local government electors in the regions of England between 2013 and 2014 and between 2014 and 2015. The South East and London saw the largest percentage changes, each with a decline of 1.6%. Generally, the falls in percentage change were smaller and more uniform across the regions than in 2013 to 2014, being between 1.0% and 1.6%. The East Midlands was the only region to see a rise in its number of parliamentary electors, growing by 0.02% compared with 2014.

Local government areas

Local government areas are unitary authorities, London boroughs and district councils in England; unitary authorities in Wales; council areas in Scotland and local government districts in Northern Ireland. At December 2015, there were a total of 391 local government areas in the UK: 326 in England, 32 in Scotland, 11 in Northern Ireland¹ and 22 in Wales.

In 2015, the size of local government electorates ranged from the 1,700 electors in Isles of Scilly to 707,800 in Birmingham. The typical size of local government electorates in 2015 varies between different areas of the country with a median across local government areas of about 89,500 in Scotland, 95,100 in England, 95,200 in Wales and 98,200 in Northern Ireland.

The changes in the number of local government districts in Northern Ireland in April 2015 prevent comparisons in the size of the local government electorate (by local government area) being made with the previous year.

The local government electorate in England, Wales and Scotland grew in 101 local government areas (27%) between 2014 and 2015. This compared with 76 areas (20%) in these countries between 2013 and 2014. However, only 59 areas had growth of more than 1.0% in their electorate; while 9 areas had growth of more than 3.0%.

Between 2014 and 2015, the local government areas with the greatest percentage growth in local government electors are all in England, as shown in Table 3. The local government area with the greatest percentage increase in Wales was the Isle of Anglesey, with an increase of 2.6% (ranked 19th in Great Britain); in Scotland, the largest increase was in Falkirk (2.0%, ranked 29th in Great Britain).

The total local government electorate in England, Wales and Scotland fell in 278 local government areas (73%) between 2014 and 2015, compared with 304 areas in these countries (80%) in the previous year. Of those, 45 areas had a fall of more than 4.0%, including 2 which fell by more than 10.0%. One area, Broxtowe, did not see any change in the number of people registered to vote in local government elections between 2014 and 2015.

The top 10 local government areas, in England, Wales and Scotland with the greatest percentage fall in local government electors are shown in Table 4. They are all in England, with the local government area of Cambridge showing the greatest percentage fall of 11.8%, followed by Canterbury with a fall of 10.6%. Both areas have large student populations. The area with the greatest fall in local government electors in Scotland was North Ayrshire with a fall of 5.1% (ranked 20th in Great Britain). In Wales, the area with the largest fall was Torfaen at 4.3% (ranked 35th in Great Britain), which contrasts with the growth in size of the electorate seen between 2013 and 2014 in Torfaen of 0.1%.

Notes for local government electors

1. On 1st April 2015, the number of Local Government Districts in Northern Ireland was reduced from 26 to 11. Some of these new Districts are exact aggregates of the former Districts. Guidance on production of official statistics for the 11 new Local Government Districts (LGD2014) is available for users from NISRA.

Other electoral statistics produced for areas in the UK include:

England

Statistics for parliamentary electors for electoral wards in England from 2010 to 2015 are available from the Boundary Commission for England. These statistics are produced from data collected from Electoral Registration Officers by ONS.

This data can be obtained from the Boundary Commission for England on request by emailing information@boundarycommissionengland.gov.uk.

Wales

Statistics for National Assembly for Wales electors by Assembly constituencies are published by the Welsh Government. Those electors who are eligible to vote in local government elections in Wales are eligible to vote in National Assembly for Wales elections. These statistics are produced from data collected from Electoral Registration Officers by ONS.

The data are available from StatsWales (please note their explanation giving details of the impact of boundary changes in some areas).

The Boundary Commission for Wales also publish statistics for the parliamentary electorate by Electoral Divisions.

Scotland

Electoral statistics for Scotland are produced and published by National Records of Scotland (NRS). Additional statistics not included in the overall UK publication cover Scottish Parliament constituencies, Scottish regions and electoral wards.

The data are available from the electoral statistics section of the NRS website.

Northern Ireland

Electoral statistics for Northern Ireland are produced and published by the Electoral Office for Northern Ireland (EONI). Monthly electoral statistics for both the parliamentary and local government electorate are available at electoral ward level from the electoral statistics section of the EONI website.