The Irish National Teachers' Organisation (INTO) (), founded in 1868, is the oldest and largest teachers' trade union in Ireland. It represents teachers at primary level in the Republic of Ireland, and at primary and post-primary level in Northern Ireland. The head office is at Parnell Square, Dublin, and there is a Northern Irish office in Belfast. The current INTO President (2025âÂÂ26) is Anne Horan; John Boyle is the General Secretary and Mark McTaggart is the Northern Secretary.
The union represents 53,000 members (46,000 in Republic of Ireland and 7,000 in Northern Ireland) as of September 2025.
Next door to the union's head office on Parnell Square is Club na Múinteoirà(the Teachers' Club) which is operated by the INTO as a space for cultural and social events, including halls, meeting rooms, a bar, and a theatre in the basement.