PurposeContemporary workplaces undergo frequent reorganizations in order to stay competitive in a working life characterized by globalization, digitalization, economic uncertainty, and ever-increased complexity. Managers are in the frontline of these challenges, leading themselves, organizations and their employees in high stress environments. This raises questions on how to support managers’ work-life sustainability, which is crucial for organizational sustainability. Mindfulness has been related to enhanced capacities to cope with challenges that are associated with organizational change. The authors evaluated short- and long-term effects of an eight-week mindfulness-based intervention in a company setting, which was going through reorganization.Design/methodology/approachForty managers (42.5% males), mean age 54.53 (SD 5.13), were randomized to the mindfulness intervention or a non-active wait-list control. Self-report data were provided on individual sustainability factors in a work context: job demands and resources, psychological detachment, i.e. possibilities for letting go of work-related thoughts during leisure, control over work-nonwork boundaries, work-life balance, and mindfulness at baseline, postintervention, and at 6-month follow-up.FindingsLinear mixed models (LMMs) analysis (all ps < 0.005 to 0.05) showed that the intervention group had a larger decrease in job demands and a smaller decrease in job resources, a larger increase in psychological detachment, work-nonwork boundary control, work-life balance, and mindfulness from baseline to postintervention when compared with the reference group. These initial effects were sustained at 6-month follow-up.Originality/valueThe study provides evidence that mindfulness practice can enhance managers’ long-term capacity to cope with challenging working conditions, and increase their work-life sustainability in times of organizational change and disruption.