Parliamentary Parties:
- Conservative Party
- Notting Hill set
- One Nation Conservatives[1]
- Blue Collar Conservative Caucus
- Centre for Policy Studies
- Conservative Christian Fellowship
- Conservative Muslim Forum
- Cornerstone Group
- Tory Reform Group
- LGBT+ Conservatives
- Conservative Women's Organisation
- Conservatives for Britain
- Bow Group
- No Turning Back
- Conservative Way Forward
- Bright Blue
- The Freedom Association
- Bruges Group
- Institute of Economic Affairs
- Selsdon Group
- Conservative Mainstream
- Conservative Monday Club
- Labour Party
- Co-operative Party
- Socialist Campaign Group
- Blue Labour
- Momentum
- Fabian Society
- Future Britain Group
- Jewish Labour Movement
- Campaign for Labour Party Democracy
- Labour for a Republic
- Compass
- Labour First
- Labour Party Marxists
- Black Rose Labour
- Labour Land Campaign
- English Labour Network
- Progress
- New Labour (1994 - 2010)
- Scottish Labour Party (1976 - 1981)
- Militant tendency (1964 - 1991)
- Highland Land League (1909 - 1920s)
- Liberal Democrats
- Green Party
- Scottish National Party (SNP)
- Alba Party
- Plaid Cymru
Extraparliamentary Parties:
- UK Independence Party (UKIP)
- Reform UK
- Reclaim Party
- Socialist Workers Party (SWP)
- For Britain Movement
- Libertarian Party
- Animal Welfare Party
- Women's Equality Party
- Left Unity
- Official Monster Raving Loony Party
- British National Party (BNP)
- Communist Party of Britain (CPB)
- Communist Party of Great Britain (Marxist-Leninist) (CPGB-ML)[2]
- National Front
- English Democrats
- Mebyon Kernow
- Heritage Party
- Northern Independence Party
- Social Democratic Party
- Britain First
- English Defence League
- All for Unity
- London Real Party
- Scottish Socialist Party
- Scottish Libertarian Party
- Solidarity
- Cornish Nationalist Party
- ↑ Despite the name, the members of this caucus are much more aligned to Cameronite Liberal Conservatism than actual (((Disraeli))) style One Nationism
- ↑ CPGB-ML reveres Vladimir Lenin, Joseph Stalin, Mao Zedong, Kim Il-sung, Enver Hoxha and Fidel Castro, whilst denouncing Trotskyism, Social Democracy, Democratic Socialism and Khrushchevism. They also believe that LGBT people are all secret Reactionaries.