INTRODUCTION: Employees working at psychiatric wards are at risk for work-related threats and violence that may impact their physical and mental health. Studies have found that crisis social support may mitigate these adverse health effects. PURPOSE: To examine the effects crisis social support on depressive symptoms 3 months after a violent or threating work incident and furthermore, to examine the effect of variations in prolonged social support on depressive symptoms during 3 months after a violent or threating incident. METHODOLOGY: After exposure to work-related violence and threats at work, the employees received a questionnaire within the first month and after 3 months. Right after the incident, 374 employees answered both the depression and crisis support items and were included in the analyses. 3 months later 276 employees answered both the depression and social support items. Prospective associations between crisis social support and depression were calculated using stepwise regressions and linear mixed models. RESULTS: Crisis social support at T1 was significantly and inversely associated with a lower level of depressive symptoms at T2, Std. Beta = - 012, t (3) = - 2.1, p = .040. Employees experiencing either a stable or increasing level of support from T1 to T2 had significantly lower levels of depressive symptoms compared to employees who experienced a decrease in support in the same period, mean differenceStable-Decreasing = 4.0 t (190) = 5.2, p = 0.006 and mean differenceIncreasing-Decreasing = 7.6, t (189) = 5.3, p < .001. CONCLUSION: The study results indicate that depressive symptoms following work-related violence or threats can be mitigated by prolonged social support. We recommend that organizations continue to offer crisis social support in the subsequent months, and not just immediately after a violent or threating incident.