While public policies increasingly rely on quantitative indicators, little attention has been paid to how household debt data is collected. Drawing on a case study conducted in India, this article compares three national surveys with a detailed, loan-by-loan survey carried out in rural areas of Tamil Nadu. The results reveal significant disparities in the measurement of indebtedness. National surveys reduce complex loan portfolios to a limited number of larger, more visible loans, and focus on borrowing from formal institutions. In contrast, detailed surveys reveal dense networks of small, intertwined and socially embedded debts. These findings have important policy implications: by underestimating the prevalence and diversity of household debt, national data may misrepresent financial vulnerability and overlook the role of informal credit networks in livelihoods. Improving measurement is therefore essential, not only to ensure data accuracy, but also to better understand the financial situation of households in the Global South.