Leader of the Opposition (Northern Ireland)

Through the existence of the Stormont Parliament, members of the Irish nationalist opposition often practiced a policy of abstentionism where they would run for seats in the parliament but refuse to take them if elected in order not to give legitimacy to British rule or the partition of the island and refused to accept recognition as the Official Opposition until 1965 despite the fact that they were the second party in the House of Commons in terms of seats won from 1925 until 1972 and had been tied for second with Sinn Féin (which was also abstentionist) in the first Northern Ireland House of Commons from 1921 to 1925.

Though the Nationalist Party was consistently the second largest party in the House of Commons its members refused to take their seats in the legislature until 1924, then resumed the abstentionist policy in the 1930s to protest the abolition of proportional representation. From 1937, Thomas Joseph Campbell and Richard Byrne were the only Nationalist MPs to take their seats until Byrne's death in 1942 and Campbell's resignation in 1945. It was not until 1965 that the Nationalist Party agreed to form the Official Opposition in the House of Commons. Eddie McAteer served as Leader of the Opposition from 1965 until he lost his seat in the 1969 election. Roderick O'Connor succeeded McAteer as Nationalist Party leader but the party again withdrew from its role as Official Opposition.

This is a list of people who served as the de facto Leaders of the Opposition of Northern Ireland, being leaders of the largest party in the House of Commons of Northern Ireland which was not the government.

No.	Name (Birth–Death)	Portrait	Constituency	Term of office		Party		Prime Minister
–	None			1921	1925				Sir James Craig (1921–40)
1	Joseph Devlin (1871–1934)		Belfast West (1925–1929) Belfast Central (1929–1934)	1925	1934		Nationalist Party
2	Thomas Joseph Campbell (1871–1946)		Belfast Central	1934	1945
									John Miller Andrews (1940–43)
									Sir Basil Brooke (1943–63)
3	James McSparran (1892–1970)		Mourne	1945	1958
4	Joseph Francis Stewart (1889–1964)		East Tyrone	1958	1964
									Terence O'Neill (1963–69)
5	Eddie McAteer (1914–1986)		Foyle	1964	1969
6	Roderick O'Connor (1910–2000)		West Tyrone	1969	1972				James Chichester-Clark (1969–71)
									Brian Faulkner (1971–72)

Pre-2022

After the introduction of power-sharing in the Northern Ireland Assembly, all willing parties who achieved adequate levels of support were invited into the Northern Ireland Executive. Starting in 2016, however, some qualifying parties choose to form an opposition. No "Leader of the Opposition" had been nominated, leaders from the opposition parties(during the 6th assembly) were as follows:[1][2]

• Eamonn McCann (2005–present; People Before Profit)[lower-alpha 1](Gerry Carroll was the party's only MLA)
• Jim Allister (2007–present; Traditional Unionist Voice)

• Clare Bailey (2018–2022; Green Party)

• Post-2022

Following the SDLP declining to nominate an Infrastructure Minister to the Executive, on the 25th of July 2022 the SDLP formed an opposition and nominated the first Leader of the Opposition for the Assembly.

• Matthew O'Toole (2022-present; Social Democratic and Labour Party)

• Parliament of Northern Ireland