Abstract Background Improving the health and wellbeing of the oldest old population is a key public health policy concern considering the rapid aging of the world’s population. The purpose of this study was to investigate the impact of the welfare state on different aspects of mental wellbeing of the oldest old population in Europe. Several approaches to measure welfare state types were compared. Methods The study used individual level data from Round 6 of the European Social Survey to measure six dimensions of mental wellbeing among the 80+ population including countries belonging to the European Union or European Economic Area. Welfare state types were measured using one welfare state- and three elderly care regime typologies, as well as three welfare state dimensions based on factor analyses of several welfare state characteristics. Welfare state impact on mental wellbeing was analysed by multilevel regression analyses, controlling for age and gender. Results The preliminary results show that universalistic and service-based regimes, as e.g. Nordic countries, are associated with higher level of subjective wellbeing and social trust, but not psychological wellbeing, compared to family-based regimes with low formal support. East Europe have lower scores on all dimensions compared to Nordic countries. The welfare state dimension capturing prioritisation of health and social services and gender equality is positively associated with all wellbeing aspects, whereas the factors capturing labour market participation of seniors and income equality respectively, are only significantly associated with subjective wellbeing and social trust. Conclusions The result point to caring approaches with high level of formal support and gender equalisation as key to enhance all aspects of mental wellbeing for the oldest old. Stimulating long duration of working life and reducing income inequalities have the potential to increase life satisfaction and happiness and social trust. Key messages Welfare state matter for the mental wellbeing in the oldest old population. General measures, supporting formal care, labour market participation and income and gender equality will also benefit the oldest old.