This paper explores whether the ‘Big 5’ personality characteristics: Emotional Stability, Extraversion, Conscientiousness, Agreeableness, and Openness to Experience, contribute to net household wealth accumulation among 1172 couple pairs (n = 2344) participating in The Irish Longitudinal Study on Ageing, independent of other socio-demographic and human capital variables. We employ quantile regression to determine whether the effects of personality vary at different levels of the conditional distribution of wealth. Results reveal that the personality characteristics of the financial respondent to the survey are more strongly associated with wealth than those of the non-financial respondent. Specifically, we find that emotional stability and extraversion are positively associated with wealth at the household level among spousal pairs. We also find that conscientiousness is positively associated with wealth, but the relationship is only significant at the lower end of the wealth continuum. In general, agreeableness and openness are negatively associated with wealth although the relationships are non-significant. These findings indicate that personality is an important factor shaping individuals’ consumption preferences and financial decision-making behaviour over the life-course.