Purpose: Work-related use of information and communication technologies (ICTs) after hours can be potentially detrimental to employee well-being. In the current study, we examine whether psychological detachment mediates the link between work-related use of ICTs after hours and fatigue and whether affective commitment exacerbates this mediated relationship.Design/methodology/approach: We collected two waves of data from 295 employees in Vietnam, with 51% being female and an average age of 37.81 years old (SD = 7.93).Findings: Work-related use of ICTs after hours was positively related to employees' fatigue via psychological detachment. The negative relationship between work-related use of ICTs after hours and psychological detachment was stronger for employees with higher affective commitment.Practical implications: Organizations are encouraged to set policies and procedures to reduce work-related use of ICTs after hours to protect employee health; when work-related use of ICTs after hours is necessary, organizations should provide employees, especially those with higher affective commitment, with resources and strategies to better detach from this experience.Originality/value: Our findings contribute to the understanding of how work-related use of ICTs after hours might adversely affect employee well-being through psychological detachment and that more committed employees can be more affected in this process.