Background and Objective: The COVID-19 pandemic has had a devastating impact globally, particularly on long-term care facilities (LTCF), in which elderly and vulnerable populations reside. In Ireland, LTCF residents were severely affected in the first wave; 3-5% of all LTCF residents died in this timeframe, accounting for 56% of all COVID-19 deaths in the country. Continued investigation of the reasons for this is vital. The aim of this research was to establish whether risk factors for high LTCF mortality established elsewhere were significantly associated with Irish LTCF performance in the first wave. Specifically, cumulative county incidence rate, facility size, occupancy rates, private vs public ownership and compliance with health inspection regulations were investigated. Methods: The main outcome considered was deaths per 100 beds. Data on crude mortality were available for 580 LTCFs up to 28 May 2020. Estimates of occupancy and compliance with regulations were averaged for these LTCFs from a novel dataset of 1130 available LTCF regulatory inspection reports up to January 2022. Focused geographic, temporal and correlation analyses looked at the relationship between deaths and studied variables. Bivariate and multivariate regression analysis was carried out to predict LTCF performance. Results: The most significant predictor of deaths from COVID-19 in LTCFs resulting from this research was cumulative COVID-19 incidence in a county followed by facility size, in concordance with international literature. Occupancy rates and ownership factors were not found to have a significant effect. Compliance with regulatory standards showed borderline significant association with worse performance. Conclusions: In conclusion, to protect LTCF residents in Ireland in the present and for potential future pandemics, attention should be paid to monitoring and suppressing local incidence rates, a move towards smaller facilities with individual rooms and closer attention to compliance with regulatory guidelines.