Mayo North was a parliamentary constituency represented in Dáil Éireann, the lower house of the Irish parliament or Oireachtas from 1923 to 1969.
The method of election was proportional representation by means of the single transferable vote (PR-STV).
[1] From 1923 to 1937, Mayo North elected 4 deputies (Teachtaí Dála, commonly known as TDs).
Following the resignation of Cumann na nGaedheal TD Joseph McGrath, a by-election was held on 11 March 1925.
Following the disqualification of Cumann na nGaedheal TD Henry Coyle, a by-election was held on 18 November 1924.