Ofsted requires UK schools to help students understand the working world and gain employability skills. However, the aims of education are much broader: Education should enable flourishing long after leaving school. Therefore, students' career decisions should be conducive to long-term flourishing beyond career readiness and educational attainment. In this mixed-methods study, we asked a representative sample of UK adults to reflect on their career decision-making processes at school and at university. We also measured current levels of self-reported objective (e.g., financial security) and subjective (e.g., subjective well-being) flourishing. The open-ended career decision reflections were coded for three moral reasoning strategies: virtue ethical, consequentialist, and deontological. Using correlations and structural equation modelling, we examined the association between the propensity for using each moral reasoning strategy in past career decisions and current flourishing. Virtue ethical moral reasoning in relation to career decision-making predicted aspects of flourishing most strongly and frequently. Consequentialist reasoning weakly and infrequently positively predicted aspects of flourishing. Deontological reasoning either did not predict flourishing at all, or negatively predicted flourishing. Our results suggest that the reasoning strategy behind career decisions people take in school or university is important to consider in UK careers provision, and current best practice.