MPs elected since 1918
| Member | Constituency | Years served |
| W. E. D. Allen |
Belfast West |
1929–1931 1 |
| William James Allen |
Armagh North Armagh |
1917–1922 1922–1948 |
| Hugh Alfred Anderson |
Londonderry North |
1918–1919 |
| Edward Mervyn Archdale |
Fermanagh North |
1916-1922 |
| C. W. Armstrong |
Armagh |
1954–1959 |
| Henry Bruce Armstrong |
Mid Armagh |
1921–1922 |
| Hugh T. Barrie |
North Londonderry |
1919–1922 |
| Charles Beattie |
Mid Ulster |
1955–1956 |
| Roy Beggs |
East Antrim |
1983–2005 |
| Robert Bradford |
Belfast South |
1977–1981 2 |
| Thomas Watters Brown |
North Down |
1918-1922 |
| Alexander Browne |
Belfast West |
1931–1943 |
| David Burnside |
South Antrim |
2001–2005 |
| David Campbell |
Belfast South |
1952–1963 |
| Edward Carson |
Dublin University Belfast Duncairn |
1892-1918 1918-1921 |
| John Carson |
Belfast North |
February 1974 – 1979 |
| Robin Vane-Tempest-Stewart, Viscount Castlereagh |
Down |
1931–1945 |
| Robert Chichester |
South Londonderry |
1921–1922 |
| Robin Chichester-Clark |
Londonderry |
1955 – February 1974 |
| Henry Maitland Clark |
North Antrim |
1959–1970 |
| Thomas Loftus Cole |
Belfast East |
1945–1950 |
| William Coote |
Tyrone South |
1916-1922 |
| James Craig |
East Down Down Mid |
1906–1918 1918-1921 |
| William Craig |
Belfast East |
1977–1979 2 |
| Knox Cunningham |
South Antrim |
1955–1970 |
| George Currie |
North Down |
1955–1970 |
| Charles Curtis Craig |
Antrim South |
1903 – 1922 |
| Herbert Dixon |
Belfast Pottinger Belfast East |
1918-1922 1922–1940 |
| Maurice Dockrell |
Dublin Rathmines |
1918-1922 |
| Jeffrey Donaldson |
Lagan Valley |
1997–2003 3 |
| Tom Elliott |
Fermanagh and South Tyrone |
2015–2017 |
| Charles Falls |
Fermanagh and Tyrone |
1924–1929 |
| Patricia Ford |
North Down |
1953–1955 |
| George Forrest |
Mid Ulster |
1956–1969 4 |
| Clifford Forsythe |
South Antrim |
1983–2000 |
| Conolly Gage |
Belfast South |
1945–1952 |
| Robert Grosvenor |
Fermanagh and South Tyrone |
1955–1964 |
| James Hamilton |
Fermanagh and South Tyrone |
1964–1970 |
| Richard Harden |
Armagh |
1948–1954 |
| H. P. Harland |
Belfast East |
1940–1945 |
| Hugh Hayes |
West Down |
1922–1922 |
| Denis Stanislaus Henry |
Londonderry South |
1916-1921 |
| Sylvia Hermon |
North Down |
2001–2010 9 |
| H. Montgomery Hyde |
Belfast North |
1950–1959 |
| William Jellett |
Dublin University |
1919–1922 |
| Peter Kerr Kerr-Smiley |
Antrim North |
Jan 1910–1922 |
| James Kilfedder |
Belfast West |
1964–1966 5 |
| North Down |
1970–1977 5 |
| Danny Kinahan |
South Antrim |
2015–2017 |
| William Arthur Lindsay |
Belfast South Belfast Cromac |
1917 – 1918 1918 – 1922 |
| James Little |
Down |
1939–1945 6 |
| James Lonsdale |
Mid Armagh |
1918 – 1921 |
| R. J. Lynn |
Belfast Woodvale Belfast West |
1918–1922 1922–1929 |
| Robert McCalmont |
Antrim East |
1913 – 1919 |
| Thomas Edward McConnell |
Belfast Duncairn; Belfast North |
1921–1922, 1922–1929 |
| Harold McCusker |
Armagh; Upper Bann |
1974–1983, 1983–1990 |
| Alan McKibbin |
Belfast East |
1950–1959 |
| Patricia McLaughlin |
Belfast West |
1955–1964 |
| J. G. MacManaway |
Belfast West |
1950 |
| Stanley McMaster |
Belfast East |
1959–1974 |
| Malcolm Macnaghten |
Londonderry North; Londonderry |
1922, 1922–1929 |
| John Maginnis |
Armagh |
1959–1974 |
| Ken Maginnis |
Fermanagh and South Tyrone |
1983–2001 |
| Stratton Mills |
Belfast North |
1959–1972 7 |
| Thomas Moles |
Belfast Ormeau Belfast South |
1918-1922 1922–1929 |
| James Molyneaux |
South Antrim; Lagan Valley |
1970–1983, 1983–1997 |
| Charles Heron Mullan |
Down |
1946–1950 |
| William Frederick Neill |
Belfast North |
1945–1950 |
| Jim Nicholson |
Newry and Armagh |
1983–1986 |
| Hugh O'Neill |
Mid Antrim Antrim North Antrim |
1915–1922 1922–1950 1950–1952 |
| Phelim O'Neill |
North Antrim |
1953–1959 |
| Lawrence Orr |
South Down |
1950–1974 |
| Sir William Hacket Pain |
South Londonderry |
1922 |
| Rafton Pounder |
Belfast South |
1953–1974 |
| Enoch Powell |
South Down |
1974–1987 8 |
| James Alexander Pringle |
Fermanagh and Tyrone |
1922–1929 |
| David Douglas Reid |
Down East Down |
1918–1922 1922–1939 |
| Ronald Ross |
Londonderry |
1929–1951 |
| William Ross |
Londonderry; East Londonderry |
1974–1983, 1983–2001 |
| Arthur Warren Samuels |
Dublin University |
1917–1919 |
| Douglas Lloyd Savory |
Queen's University, Belfast; South Antrim |
1940–1950, 1950–1955 |
| Robert Sharman-Crawford |
Mid Down |
1921–1922 |
| John Morrow Simms |
North Down; Down |
1922, 1922–1931 |
| Thomas Sinclair |
Queen's University, Belfast |
1918–1940 |
| Walter Smiles |
Down; North Down |
1945–1950, 1950–1953 |
| Martin Smyth |
Belfast South |
1982–2005 |
| Thomas Somerset |
Belfast North |
1929–1945 |
| William Stewart |
Belfast South |
1929–1945 |
| John Taylor |
Strangford |
1983–2001 |
| Thomas Teevan |
Belfast West |
1950–1951 |
| William Thompson |
West Tyrone |
1997–2001 |
| David Trimble |
Upper Bann |
1990–2005 |
| Cecil Walker |
Belfast North |
1983–2001 |
| Thomas Browne Wallace |
West Down |
1921–1922 |
| William Wellwood |
Londonderry |
1951–1955 |
| Harry West |
Fermanagh and South Tyrone |
February–October 1974 |
| William Whitla |
Queen's University of Belfast |
1918–1923 |
| Daniel Martin Wilson |
West Down |
1918-1921 |
| Henry Wilson |
North Down |
February–July 1922 |
- 1 Defected to the New Party.
- 2 Elected in 1974 for the Vanguard Unionist Progressive Party.
- 3 Defected to the Democratic Unionist Party.
- 4 Elected in 1956 as an Independent Unionist.
- 5 Left the party to become an Independent Unionist before forming the Ulster Popular Unionist Party.
- 6 Resigned from the party at the 1945 general election in protest at being subject to a reselection due to the retirement of Viscount Castlereagh, the other Ulster Unionist MP for the two member Down constituency and held his seat as an Independent Ulster Unionist.
- 7 Refused to follow the other Ulster Unionists in resigning the Conservative whip; later joined the Alliance Party of Northern Ireland.
- 8 Previously Conservative MP for Wolverhampton South West 1950–1974.
- 9 Left the party on 25 March 2010 to become an Independent Unionist.