Ample evidence indicates that unfairness at the workplace (organizational injustice) is associated with both job attitudes and health of employees. Several factors that influence these associations have been identified: e.g., personality traits, such as the Big Five traits, justice sensitivity, type of occupation (e.g., white-collar), and unobserved time-invariant factors. Previous studies only addressed parts of these issues, and the ideal research design to mitigate biases-an experiment with random assignment to a treatment and control group-is not feasible. This study therefore mimics a randomized experiment using two statistical techniques.First, matching was implemented to balance the treatment and control group in confounding factors (demographics and personality) in two prospective waves (2012-2014) of observational data (4522 white-collar, 2984 blue-collar) taken from the Linked Personnel Panel, which is an employee survey representative for German private sector companies with more than 50 employees. Second, a difference-in-difference approach excludes unobserved time-invariant factors by estimating associations of changes in organizational justice (distributive, procedural, interactional) with job attitudes (job satisfaction, turnover intention) and health (general and mental) in these groups, separate for white- and blue-collar employees.A decrease in perceived justice was associated with lower job attitudes (less job satisfaction and higher turnover intentions), while an increase was associated with higher values. This pattern was found for white- and blue-collar workers and also for health indicators, with the latter, however, being less pronounced.Increased fairness at the workplace is related to better job attitudes and health for white- and blue-collar employees, independent of personality traits and unobserved time-invariant factors.