Diocese of Tuam, Killala and Achonry

An engraving of St Mary's Cathedral, Tuam, as rebuilt in the 1870s and completed in 1878.

The Diocese of Tuam, Killala and Achonry (also known as the United Dioceses of Tuam, Killala and Achonry) is a former diocese in the Church of Ireland located in Connacht; the western province of Ireland. It was in the ecclesiastical province of Armagh. Its geographical remit included County Mayo and part of counties Galway and Sligo. In 2022, the diocese was amalgamated into the Diocese of Tuam, Limerick and Killaloe.