The 1st House of Commons of Northern Ireland was elected at the 1921 Northern Ireland general election.

All members of the Northern Ireland House of Commons are listed. Only Unionist members took their seats. Sinn Féin members sat instead in the republicans Second Dáil, alongside those elected to the Southern Ireland House of Commons; while Nationalist Party members refused to sit in either the Northern Ireland Parliament or the republican Dáil.

Sir James Craig, (later Viscount Craigavon) was appointed Prime Minister of Northern Ireland on 7 June 1921.

Members NameConstituency PartyMilne BarbourAntrim  Unionist PartyMaj. Hon. Robert William O'NeillAntrim  Unionist PartyGeorge Boyle HannaAntrim  Unionist PartyRobert CrawfordAntrim  Unionist PartyRobert MegawAntrim  Unionist PartyJohn Fawcett GordonAntrim  Unionist PartyJoseph DevlinAntrim  Nationalist Party Richard BestArmagh  Unionist PartyMichael CollinsArmagh  Sinn FéinMaj. David ShillingtonArmagh  Unionist PartyJohn Dillon NugentArmagh  Nationalist Party Sir Dawson BatesEast Belfast  Unionist PartyCapt. Herbert DixonEast Belfast  Unionist PartyThompson DonaldEast Belfast  Unionist PartyJames Augustine DuffEast Belfast  Unionist PartyLloyd CampbellNorth Belfast  Unionist PartySamuel McGuffinNorth Belfast  Unionist PartyWilliam GrantNorth Belfast  Unionist PartyRobert McKeownNorth Belfast  Unionist PartyThomas MolesSouth Belfast  Unionist PartyHugh PollockSouth Belfast  Unionist PartySir Crawford McCullaghSouth Belfast  Unionist PartyJulia McMordieSouth Belfast  Unionist PartyThomas Henry BurnWest Belfast  Unionist PartyRobert LynnWest Belfast  Unionist PartyWilliam TwaddellWest Belfast  Unionist PartyJoseph DevlinWest Belfast  Nationalist Party Sir James Craig, BtDown  Unionist PartyÉamon de ValeraDown  Sinn FéinJ. M. AndrewsDown  Unionist PartyThomas LaveryDown  Unionist PartyCapt. Hon. Harry MulhollandDown  Unionist PartyRobert McBrideDown  Unionist PartyThomas McMullanDown  Unionist PartyPatrick O'NeillDown  Nationalist Party Arthur GriffithFermanagh and Tyrone  Sinn FéinEdward ArchdaleFermanagh and Tyrone  Unionist PartyWilliam CooteFermanagh and Tyrone  Unionist PartySeán MilroyFermanagh and Tyrone  Sinn FéinWilliam Thomas MillerFermanagh and Tyrone  Unionist PartyJames CooperFermanagh and Tyrone  Unionist PartySeán O'MahonyFermanagh and Tyrone  Sinn FéinThomas HarbisonFermanagh and Tyrone  Nationalist Party Sir Robert AndersonLondonderry  Unionist PartyEoin MacNeillLondonderry  Sinn FéinDehra ChichesterLondonderry  Unionist PartyJohn Martin MarkLondonderry  Unionist PartyGeorge LeekeLondonderry  Nationalist Party Dr John CampbellQueen's University of Belfast  Unionist PartyProf. Robert JohnstoneQueen's University of Belfast  Unionist PartyJohn Hanna RobbQueen's University of Belfast  Unionist PartyDr Hugh Morrison Queen's University of Belfast  Unionist Party

Notes Joseph Devlin was elected for both Antrim and Belfast West, but did not take either seat in parliament. Maj. Hon. Robert William O'Neill was Speaker of the House from 7 June 1921 to 2 May 1929.

Changes William Twaddell (UUP, Belfast West) was assassinated by the IRA on 22 May 1922. The by-election on 2 May 1923 was won by Philip James Woods (Independent Unionist).

References Biographies of Members of the Northern Ireland House of Commons