Sligo Hospital was one of the most overcrowded facilities in the country during the month of May.
Figures released by the Irish Nurses and Midwifes Organisation show it was the fourth most overcrowded just below University Hospital Galway.
751 patients waited on trolleys or chairs at the Northwest facility this month while 896 were left without a bed at University Hospital Galway.
University Hospital Limerick dealt with the highest attendance throughout the month with 1857 people on trolleys.
The INMO say the numbers on trolleys in the month of May are higher than January 2023, when the worst levels of daily hospital overcrowding were seen since the INMO began counting trolleys.