This paper analyses the relationship between ageing and personal retirement savings plan participation in the Portuguese population, taking into account heterogeneity and endogeneity in preferences. A mixed logit model is used to analyse the determinants of retirement saving behaviour, allowing for heterogeneity and endogeneity in the responses. We find considerable heterogeneity among individuals (in terms of socio-economic variables such as age, gender and income), which must be taken into account by any policy aimed at changing retirement saving behaviour
