PurposeDrawing on social exchange literature, this study explores the mediating role of affective commitment between employees' assessments of contract breaches and opportunistic silence, along with the invigorating effect of hostile attribution bias.Design/methodology/approachWe tested the hypotheses using multi-wave data collected from employees working in higher education institutions in Pakistan.FindingsPerceived contract breaches elicit intentional, selfish and retaliatory motives of silence, largely because employees lack emotional attachments to their organization. This mechanism is more prominent among employees who tend to blame others and perceive them as antagonistic even when they are not.Practical implicationsFor human resource managers, this investigation highlights a crucial feature – affective commitment – by which employees' perceptions of psychological contract breaches facilitate opportunistic silence. Our results suggest that this process is more likely to intensify when employees have distorted thinking, motivating them to attribute the worst motives to their employer's actions.Social implicationsPerceived contract breaches within universities can have far-reaching societal consequences, affecting trust, reputation, economic stability, and the overall quality and accessibility of education and research. Addressing and preventing such breaches is essential to maintaining the positive societal role of universities.Originality/valueThis study provides novel insights into the process that underlies the connection between perceived contract breach and opportunistic silence by revealing the hitherto overlooked role of employees' hostile attribution bias, which renders them more susceptible to experiencing unfavorable forms of social exchange.