To increase understanding of the relationships between organisational justice, affective commitment and turnover intention in health care. Turnover in health care is a serious concern, as it contributes to the global nursing shortage and is associated with declines in quality of care, patient safety and patient outcomes. Turnover also impacts care teams and is associated with decreased staff cohesion and morale. A survey was developed and administered to frontline nurses working in the Province of Ontario, Canada. The data were used to test a hypothetical model developed from a review of the literature. The relationships amongst the three constructs were evaluated using structural equation modelling and mediation analysis. The hypothesised model was generally supported, although we were limited to considerations of interpersonal justice, affective commitment to one's organisation and turnover intention. Interpersonal justice is associated with affective commitment to one's organisation, which is negatively associated with turnover intention. Interpersonal justice was also found to be directly and negatively associated with turnover intention. Affective commitment to one's organisation was also found to mediate the relationship between interpersonal justice and turnover intention. The examination of relationships within the "employee retention triad" in a single, comprehensive model is novel and provides new information regarding relational complexity and insights into what healthcare leaders can do to retain employees. Reducing turnover may help to decrease some of the stressors related to turnover for clinical staff remaining at the organisation such as constant onboarding and orientation of new hires, working with less experienced staff and increased workload due to decreased staffing. © 2018 John Wiley & Sons Ltd.