Abstract Background Sociodemographic characteristics of suicides are available from Statistics Netherlands. To improve suicide prevention, it is not only necessary to know who dies but also why people die. A psychosocial autopsy was conducted in the Netherlands to investigate differences in psychosocial characteristics and precipitating factors of suicides of young (<30) and middle-aged (40-70) suicide decedents. Methods Data were collected from bereaved individuals. A questionnaire detailed sociodemographic and psychosocial characteristics of the decedents. We reconstructed the suicidal process in the months preceding the suicide in an interview. Findings from the questionnaire and interview were integrated. An independent expert committee formulated recommendations for suicide prevention. Results 162 suicides were investigated. Young decedents showed high levels of substance use and academic pressure. Young adults with developmental disorders were vulnerable in the transition to adulthood. Young males reached out less to support and care. By contrast, suicides of young females were distinguished by comorbidity of psychiatric disorders, frequent suicidal behaviours, high levels of care use, wait lists and a loss of (treatment) perspective, harmful social media use and bullying. Work and financial problems were common in middle-aged decedents. Physical disability and pain were frequently mentioned for middle-aged females. Suicide in middle-aged males was characterized by financial distress, interpersonal conflicts such as divorce, high levels of binge drinking and addiction. Conclusions Our data provide a topology of the needs of individuals at risk for suicide. Suicide prevention strategies can be improved by better transition support and explicit suicide monitoring in young adults with a developmental disorder, active waitlist policies in mental healthcare, and improved collaboration between debt counsellors and mental care professionals based on shared accountability. Key messages • Bereaved individuals elucidated a wide range of psychosocial problems in suicide decedents. • Suicide prevention should adhere to a needs-based approach.