Although Northern Ireland is a part of the United Kingdom, it has a quite distinct party system from the rest of the country, as the Labour Party and Liberal Democrats do not contest elections there (though the Liberal Democrats have links with the Alliance Party), and the Conservative Party has received only limited support in recent elections. Party affiliation is generally based on religious and ethnic background.
The Northern Ireland Assembly is elected by single transferable vote and the composition of the Northern Ireland Executive is by power sharing determined by the D'Hondt system, among the members elected to the assembly. Northern Ireland also elects 18 MPs to the House of Commons, and there are elections to 11 local government districts.
Some parties, such as Sinn Féin and the Workers' Party, are organised on an all-Ireland basis. Others such as the Conservative Party are organised on an all-United Kingdom basis. There are many Northern Ireland-specific parties and these, on the whole, predominate.
The distinction between "unionist/loyalist", "nationalist/republican" and "other" is not always easy with some parties and individuals. Some have defined themselves less by their position on the "Border Question" than on other political issues.
For example, the former Republican Labour Party/Social Democratic and Labour Party MP Gerry Fitt's career suggests he was first and foremost a socialist rather than a nationalist and he eventually left the SDLP claiming it had drifted from its founding intentions. Similarly the Workers' Party has its roots in the republican Official IRA but nowadays is considered to be a non-violent socialist and nationalist party. Several parties strive to be avowedly non-sectarian and would not consider themselves to be either unionist or nationalist. The Northern Ireland Assembly requires MLAs to designate themselves either "Unionist", "Nationalist" or "Other". This is a designation that is particularly resented by those who designate as "Other", as they have no input on who becomes First or Deputy First Minister.
There are some who see the terms "Unionist"/"Loyalist" and "Nationalist"/"Republican" as being of more relevance to the community that the party seeks to represent rather than the position on the border question. Several of the "Other" parties strive to be non-sectarian but have a clear position on the border.
Political parties with elected representation at a local, national, or UK level
Party details Party FoundedPoliticalpositionIdeology DesignationLeader(s) Localgovernment NI Assembly House ofCommons(NI Seats) House ofLordsSinn Féin1905 Nationalist Michelle O'Neill Democratic Unionist Party1971 Right-wing"It will be ‘difficult’ for May to survive, says N Ireland’s DUP", By Vincent Boland & Robert Wright. Financial Times. 9 June 2017. Retrieved 10 June 2017."Who Are The DUP? The Democratic Unionist Party Explained", LBC. 9 June 2017. Retrieved 10 June 2017. Unionist Gavin Robinson Alliance Party1970 Centre tocentre-leftArdle, Mc; Gén., Or. (16 August 2023). "Travail écrit : "Stormont's ugly scaffolding : How the Northern Irish political institutions reinforce "green and orange"voting."". Université de Liège, Liège, Belgique. Retrieved 3 September 2026. Despite the UUP's attempts at advocating social liberalism, Tonge thinks that the UUP looks dated and stale to many young unionists, and that the social liberal body within the UUP membership remains relatively small, with most liberal unionists voting instead for Alliance who, at a minimum, are not advocating for a united Ireland. ... There are a few younger members of Alliance now who are not as keen on the label centrist, because they do see themselves as centre-left, and they see themselves as progressive, and they argue that they've been at the forefront on campaigns of social liberalism, such as abortion rights and same-sex marriage.Jarrett, Henry (2016). "The Single Transferable Vote and the Alliance Party of Northern Ireland". Representation. 52 (4): 311–323. doi:10.1080/00344893.2017.1301987. S2CID 157208657. This could be achieved by, for example, adopting a more conservative position than Alliance's centre-left liberalism... Other Naomi Long Ulster Unionist Party1905 Centre-right Unionist Jon Burrows Social Democratic and Labour Party1970 Centre-left Nationalist Claire Hanna Traditional Unionist Voice2007 Right-wing British unionismNational conservatismSocial conservatismHard EuroscepticismThree Compelling Reasons to Vote Leave . Traditional Unionist Voice (official website). Published 20 June 2016. Retrieved 2 October 2017. Unionist Jim Allister People Before Profit2005 Left-wing to far-left Other Richard Boyd Barrett Green Party NI1985 Centre-leftto left-wing Other Malachai O'Hara Progressive Unionist Party1985 Unionist Russell Watton Aontú 2019 Fiscal: left-wingSocial: right-wing Nationalist Peadar Tóibín NI Conservatives1989 Centre-rightto right-wing Unionist Paul Leeman Labour Party2003 Centre-left Unionist Erskine Holmes Liberal Democrats1988Centre to centre-left Unionist Stephen Glenn
Party representation Party Representation (as of 12 September 2026) UK Parliament Assembly Local councils House of Commons House of Lords Sinn Féin 7 0 27 144 Democratic Unionist Party 5 6 25 122 Alliance Party of Northern Ireland 1 0Lord Alderdice, leader of the Alliance from 1987–98, has sat in the Lords since 1996, taking the Lib Dem whip. 17 67 Ulster Unionist Party 1 2 9 54 Social Democratic and Labour Party 2 0Margaret Ritchie, leader of the SDLP from 2010–11, has sat in the Lords since 2019, resigning from the party to do so. 8 39 Traditional Unionist Voice 1 0 1 10 People Before Profit 0 0 1 2 Green Party Northern Ireland 0 0 0 5 Progressive Unionist Party 0 0 0 1 Aontú 0 0 0 1 Northern Ireland Conservatives 0 1 0 0 Labour Party in Northern Ireland0100Northern Ireland Liberal Democrats0100
Other registered parties Unionist and loyalist Party FoundedPoliticalpositionIdeologyLeader(s) Heritage Party2020Right-wing David Kurten
Nationalist and republican Party FoundedPoliticalpositionIdeologyLeader(s) Communist Party of Ireland 1933 Far-left Communism Marxism-Leninism Jimmy Corcoran Fianna Fáil 1926 CentreFianna Fail on election footing now, says Martin . Irish Independent. Author – Daniel McConnell. Published 1 January 2015. Retrieved 18 July 2017.Micheal Martin to replace Brian Cowen as Fianna Fail leader . The Telegraph. Published 26 January 2011. Retrieved 18 July 2017.Weakened Irish PM faces delicate balancing act . EUobserver. Author – Shona Murray. Published 12 May 2016. Retrieved 18 July 2017. tocentre-right Micheál Martin Irish Republican Socialist Party1974Far-left Ard Chomhairle Republican Network for Unity2007 Left-wing Saoradh 2016 Far-left Stephen Murney Workers' Party 1970Far-left Collective leadership
Others Party FoundedPoliticalpositionIdeologyLeader(s)Notes Cross-Community Labour Alternative2015Left-wing Owen McCracken Socialist Party1996Left-wing to far-left Democratic socialismPolitical radicalismTrotskyismRoutledge Handbook of European Elections. Edited by Donatella M.Viola. Published by Routledge. First published in 2016, in Oxon, United Kingdom. Accessed via Google Books.Euroscepticism Collective leadership
Unregistered parties Candidates for unregistered parties may choose either to be listed as "Non-Party", or to leave the section blank on the ballot paper, in the same manner as independent candidates.
Nationalist and Republican 32 County Sovereignty Movement - Does not contest elections, operates as a pressure group Anti-Imperialist Action Ireland - Does not contest elections Fine Gael National Party Republican Sinn Féin (RSF)
Unionist Reform UK Advance UK
Inactive parties Unionist and loyalist Belfast Labour Party British Ulster Dominion Party Commonwealth Labour Party Independent Unionist Association Labour Unionist Party NI21 UKIP Northern Ireland Northern Ireland Unionist Party - deregistered 2008 Protestant Coalition Ulster Defence Party* (UDP) Protestant Unionist Party (evolved into the DUP) Ulster Constitution Party Ulster Democratic Party Ulster Loyalist Democratic Party Ulster Popular Unionist Party Ulster Progressive Unionist Association Ulster Protestant League Ulster Resistance Ulster Unionist Labour Association Unionist Party of Northern Ireland United Kingdom Unionist Party - deregistered 2008 United Ulster Unionist Council United Ulster Unionist Party United Unionist Coalition (UUC) Vanguard Progressive Unionist Party Volunteer Political Party
Nationalist and Republican All Ireland Anti-Partition League Federation of Labour Fianna Uladh Irish Anti-Partition League Independent Socialist Party Irish Independence Party National Democratic Party National League of the North National Unity Nationalist Party Northern Council for Unity Official Sinn Féin (now Workers' Party) People's Democracy Red Republican Party Republican Congress Republican Labour Party Saor Éire Socialist Republican Party Unity
Others Commonwealth Labour Party Communist Party of Ireland (Marxist-Leninist) Communist Party of Northern Ireland Irish Labour Party (contests elections in the Republic) Labour coalition Labour Party of Northern Ireland Northern Ireland Labour Party Northern Ireland Women's Coalition Newtownabbey Labour Party Newtownabbey Ratepayers Association Natural Law Party Social Democratic Party - The post-1988 rump of the party stood in a Northern Ireland by-election in 1990; the party as a whole existed and was more prominent in Great Britain from 1981 to 1988 although the post-1990 rump group still exists. Ulster Independence Movement Ulster Liberal Party Ulster Movement for Self-Determination United Labour Party (Northern Ireland) Ulster Third Way - deregistered 2005 Veritas - Dissolved June 2015 Vote for Yourself Party - disbanded April 2009, de-registered 8 June 2009 World Socialist Party (Ireland) - Dissolved in the 1990s
Flowchart of all political parties in Northern Ireland
Party leaders Party leaders serving 10 years or more are Leader Years Party/Period ConstituencyIan Paisley 42y Protestant Unionist Party 1966–1971Democratic Unionist Party 1971–2008 Bannside, North AntrimRuairí Ó Brádaigh 36y Sinn Féin 1970–1983Republican Sinn Féin 1986–2009 Gerry Adams 35y Sinn Féin 1983–2018 West Belfast, LouthWilliam Norton 28y Irish Labour 1932–1960 Tomás Mac Giolla 26y Sinn Féin 1962–1970Official Sinn Féin 1970–1977Sinn Féin The Workers' Party 1977–1982Workers' Party 1982–1988 Hugh Smyth 23y Progressive Unionist Party 1979–2002 John Hume 22y Social Democratic and Labour Party 1979–2001 FoyleAlbert McElroy 19y Ulster Liberal Party 1956–1975 (?) Lord Craigavon 19y Ulster Unionist Party 1921–1940 Down, North DownJohn Redmond 18y Irish Parliamentary Party 1900–1918 Waterford CityLord Brookeborough 17y Ulster Unionist Party 1946–1963 LisnaskeaJames Molyneaux 16y Ulster Unionist Party 1979–1995 South Antrim, Lagan ValleyJoseph Devlin 16y Nationalist Party 1918–1934 Belfast Falls, Fermanagh and Tyrone, Belfast CentralGerry Fitt 15y Republican Labour Party 1964–1970Social Democratic and Labour Party 1970–1979 Belfast West, Belfast DockJames Kilfedder 15y Ulster Popular Unionist Party 1980–1995 North DownDavid Ford 15y Alliance Party 2001–2016 South AntrimMargaret Buckley 13y Sinn Féin 1937–1950 Robert McCartney 13y UK Unionist Party 1995–2008 North DownJames McSparran 13y Nationalist Party 1945–1958 MourneOliver Napier 12y Alliance Party 1972–1984 Belfast EastThomas Joseph Campbell 11y Nationalist Party 1934–1945 Belfast CentralSir Edward Carson 11y Ulster Unionist Party 1910–1921 Dublin University, Belfast DuncairnJohn Alderdice 11y Alliance Party 1987–1998 Belfast EastDavid Trimble 10y Ulster Unionist Party 1995–2005 Upper Bann
See also Politics of Northern Ireland Lists of political parties Political make-up of local councils in Northern Ireland Reform UK–TUV alliance List of political parties in the Republic of Ireland