Elections in Northern Ireland are held on a regular basis to local councils, the Northern Ireland Assembly and to the Parliament of the United Kingdom. The Northern Ireland Assembly has 90 members, elected in 18 five-member constituencies by the single transferable vote (STV) method. Northern Ireland is represented at Westminster by 18 single-member constituencies elected by the first-past-the-post method. Unlike in the rest of the United Kingdom, elections in Northern Ireland are administered centrally by the Chief Electoral Officer for Northern Ireland and the Electoral Office for Northern Ireland rather than by local authorities. Elections to the United Kingdom House of Commons Legend U: Unionist; N: Nationalist; O: Other. Sinn Féin have never taken their seats in the United Kingdom House of Commons due to their policy of abstentionism. UUP MPs sat as members of the Conservative Party until 1972. By-elections Gains are marked with a grey background. Recall petition 2018 North Antrim recall petition Referendums Northern Ireland-specific referendums 1973 Northern Ireland border poll 1998 Northern Ireland Good Friday Agreement referendum United Kingdom-wide referendums 1975 United Kingdom European Communities membership referendum#Results by United Kingdom constituent countries 2011 United Kingdom Alternative Vote referendum#Results by constituent countries 2016 United Kingdom European Union membership referendum#Results by constituent countries & Gibraltar Elections to the Northern Ireland Assembly Legend U: Unionist; N: Nationalist; O: Other. 1998 Northern Ireland Assembly election 2003 Northern Ireland Assembly election 2007 Northern Ireland Assembly election 2011 Northern Ireland Assembly election 2016 Northern Ireland Assembly election 2017 Northern Ireland Assembly election 2022 Northern Ireland Assembly election Elections to the European Parliament From 1979 to 2020, three of the seats in the European Parliament allocated to the United Kingdom formed a three-seat constituency elected by single transferable vote. It differed from European Parliament constituencies elsewhere in the United Kingdom which used the D'Hondt method. The United Kingdom withdrew from the European Union on 31 January 2020, and the constituency was abolished. Ad hoc elections 1973 Northern Ireland Assembly election Northern Ireland Constitutional Convention (election in 1975) 1982 Northern Ireland Assembly election Northern Ireland Forum (election in 1996) Elections to the Northern Ireland House of Commons 1921 Northern Ireland general election 1925 Northern Ireland general election 1929 Northern Ireland general election 1933 Northern Ireland general election 1938 Northern Ireland general election 1945 Northern Ireland general election 1949 Northern Ireland general election 1953 Northern Ireland general election 1958 Northern Ireland general election 1962 Northern