Objective Reducing the number of adverse patient safety incidents (PSIs) requires careful monitoring and active management processes. However, there is limited information about the association between hospital settings and the type of PSI. The aims of this study were to describe the severity, nature and characteristics of PSIs from an analysis of their incidence and to assess the relationships between the type of PSI and its setting. Methods A retrospective audit of a clinical incident management system database was conducted for a tertiary health service in Australia with 620000 residents. Records of PSIs reported for patients between 1 July 2017 and 30 June 2018 with Safety Assessment Codes (SAC) of PSIs were extracted from the clinical incident management system and analysed using descriptive and inferential statistics. PSIs involving paediatrics, mental health and primary care were excluded. Results In all, 4385 eligible PSIs were analysed: 24 SAC1, 107 SAC2 and 4254 SAC3 incidents. Across reported PSIs, the most common incidents related to skin injury (28.6%), medication (23.2%), falls (19.9%) and clinical process (8.5%). Falls were reported significantly more often in the medical division (χ2=43.85, P<0.001), whereas skin injury incidents were reported significantly more often in the surgical division (χ2=22.56, P<0.001). Conclusions A better understanding of the nature of PSIs and where they occur may lead to more targeted quality improvement strategies. What is known about this topic? Improving patient safety requires effective safety learning systems, which include incident reporting and management processes. Although incident reporting systems typically underestimate the incidence of iatrogenic harm, they do provide valuable opportunities to improve the future safety of health care. What does this paper add? This study reports the extent and severity of different types of PSIs that typically occur in a large tertiary hospital in Australia. The most common types of incidents are skin injury, falls, medication errors and clinical process. There are empirical associations between the type of PSI and clinical division (medical, surgical). What are the implications for practitioners? A greater understanding of the types of PSI and the settings in which they occur may inform the development of more targeted quality improvement strategies that potentially reduce their incidence.