In developing countries, where health insurance is not a commonly purchased financial instrument, recent debates have revolved around extending health insurance coverage to a wider range of the population, primarily via compulsory insurance schemes. However, these debates rarely consider the competing demands placed on the family budget, which will influence the acceptability of the program by the populace. In this paper, we draw on data from the 2000 income and expenditure survey to examine treatment effects associated with household insurance status, providing a detailed examination of expenditure substitution patterns within South Africa. In agreement with economic theory, the expansion of health insurance coverage via compulsory schemes creates additional burdens for households, which households accommodate via expenditure substitution. The observed variation in the household’s ability to accommodate increased expenditure can and should be used in future to assess policy options and in the design of an optimal social health insurance program.