Default nudges tend to improve financial well being. How do educative nudges, providing simple individually targeted financial literacy training, fare in comparison? In a preregistered experiment on the self-management of online retirement accounts, we compared the effects of educative and default nudges on savings, financial errors, and institutional trust. Participants allocated monetary endowments between alternative savings accounts with varying risk and rates of return, some of which were pay-off dominated. Defaults substantially increased savings and decreased errors, but educative nudges had no impact. We explored the cognitive correlates of financial decisions using tests of cognitive reflection, financial institutional knowledge, and financial literacy that distinguish between the comprehension of annual interest and interest compounding. Tendency for cognitive reflection and financial literacy in general and the comprehension of interest compounding in particular predicted successful financial self-management. Educative nudges are promising, but better educative techniques are needed to complement or replace default nudges.