BackgroundLife-course socioeconomic factors may have a role in dementia aetiology but there is a current paucity of studies. Meta-analyses of individual participant data would considerably strengthen this evidence base.AimsTo examine the association between socioeconomic status in early life and adulthood with later dementia death.MethodIndividual participant meta-analysis of 11 prospective cohort studies (1994–2004, n = 86508).ResultsLeaving full-time education at an earlier age was associated with an increased risk of dementia death in women (fully adjusted hazard ratio (HR) for age ⩽14 v. age ⩾16: HR = 1.76, 95% Cl 1.23–2.53) but not men. Occupational social class was not statistically significantly associated with dementia death in men or women.ConclusionsLower educational attainment in women was associated with an increased risk of dementia-related death independently of common risk behaviours and comorbidities.