We report the results of a longitudinal intervention with students across 5 universities in China designed to reduce online consumer debt. We allocate participants to either a financial literacy treatment group, a self-control treatment group, or a zero-touch control group. Our self-control training intervention features detailed tracking of spending and borrowing, budgeting, and introspection about consumption choices. This intervention reduces online borrowing and delinquency charges, mainly driven by a reduction in entertainment-related spending and borrowing. In contrast, financial literacy interventions improve test scores but only marginally affect borrowing. Our results suggest that cultivating self-regulation and budgeting skills can improve borrowing behavior on e-commerce platforms.