The Suicide Observatory in Cork and Kerry was established to address the urgent need for real-time suicide data in Ireland to enable timely suicide prevention. This study aimed to assess the performance and efficiency of the Suicide Observatory to inform decisions about its upscaling and wider implementation. We designed a mixed-methods approach and used Centers for Disease Control and Prevention evaluation guidelines to assess key attributes of the Observatory: sensitivity, positive predictive value, data quality, timeliness, simplicity, accessibility, acceptability, and the overall usefulness. We compared data obtained from an audit of the Observatory for 2019-2020 with coroner-determined suicide cases and national suicide mortality data, and conducted semistructured interviews with stakeholders. We found that the Suicide Observatory in Cork shows a high level of data quality (sensitivity: 83.72%; 95% CI = 74.20%-90.80%), positive predictive value: 75.79% (95% CI = 74.04%-77.46%), data missingness: <2%). It applied a fortnightly case submission interval, and participants generally regarded the data collection as straightforward. The Suicide Observatory data were made available to stakeholders and decision makers. Participants reported strong acceptability, primarily due to its simplicity and accessibility. The overall usefulness of the Suicide Observatory was considered to be high as it improved the understanding of the suicide demography in the regions and enabled timely suicide prevention initiatives and support for affected communities. It was concluded that the Suicide Observatory has high levels of performance and efficiency and has been crucial for timely suicide prevention. The findings support its wider implementation in Ireland.