As of July 2019, Labour had 485,000 members, compared to the Conservatives, who had 180,000 members. The SNP had around 125,500 members (December 2018), the Liberal Democrats 115,000 (August 2019), Green Party 48,500 (July 2019), UKIP 29,000 (April 2019) and Plaid Cymru 10,000 (October 2018). Party membership has risen notably since 2013, both in total and as a percentage of the electorate. This briefing paper will be updated as further information on party membership levels becomes available.Jump to full report >>
This paper presents party membership data published by the Electoral Commission together with the latest estimates from political parties’ head offices, press releases, media reports and academic studies. It will be updated as further information on party membership levels becomes available.
Comparing party membership between political parties can sometimes be difficult. Political parties are under no legal obligation to publish membership statistics. There is also no uniformly recognised definition of membership, nor is there an established method or body to monitor it. Nonetheless, the majority of main parties voluntarily include membership figures in annual accounts for the year ending 31 December, submitted to the Electoral Commission.
Although all parties are required to submit these annual accounts by the Political Parties, Elections and Referendums Act (2000), they are not obliged to include membership data. When annual accounts do include these figures, they’re probably the most reliable estimates available.
Data provided on request from party head offices to the House of Commons Library is an alternative reliable source of information. It is used for the latest estimates when possible.
Estimates from political parties’ head offices, press releases and media reports indicate that:
The latest available data suggests that in 2019 the Conservative Party is the second-largest in the UK, having fallen behind that of the SNP in 2018 (assuming that SNP party membership has not increased greatly since 2018). In 2018, SNP party membership rose from 118,162 (April) to 125,482 (August), according to information provided by the party headquarters.
Membership as proportion of electorate
Membership of the Conservative, Labour and the Liberal Democrat parties has increased to around 1.7% of the electorate in 2019, compared to a historic low of 0.8% in 2013. Across the UK, the Labour Party’s membership increased from 0.4% in 2013 to 1.2% in 2017, before falling to an estimated 1.1% in April 2018. Across Scotland, assuming all Scottish National Party members are in Scotland, SNP membership increased from 0.6% of the electorate in 2013 to around 3% in 2018.
Political parties are under no legal obligation to publish membership statistics. Many parties provide party membership figures for the year ending 31 December in annual accounts submitted to the Electoral Commission. The latest estimates released by the Electoral Commission shows that in December 2018:
This paper includes Party Membership Project data. The project is funded by the Economic and Social Research Council and run by Tim Bale, Paul Webb and Monica Poletti - academics from Queen Mary University of London and University of Sussex
Academic surveys suggest that in 2017, more than half of members of the main six parties belonged to a higher (ABC1) social grade. The highest rates of ABC1 members were among the Liberal Democrats and the Conservatives, the lowest among UKIP and SNP members. Fewer than half of all members were women and fewer than six percent have ever stood for an office within a party organisation.
This note uses a range of sources to examine party membership and support in the UK, specifically membership levels and the social characteristics of party members. For context, it also provides data on membership to non-party political organisations including trade unions, charities and campaigns.
Commons Briefing papers SN05125
Authors: Lukas Audickas; Noel Dempsey; Philip Loft
Topic: Political parties