In Brazil, there exists a two-tiered system of healthcare access. Those with sufficient means have access to a private system of healthcare that provides quality treatment on demand, while the remainder of the country relies on an overburdened system of public clinics and hospitals. Household survey data are used to determine which socio-demographic groups rely most on this public healthcare system. Current demographic trends suggest that the public healthcare infrastructure will become more and more heavily used in the coming decades. A stylized model of healthcare choice is estimated, and its parameters are used to conduct counterfactual simulations of the welfare implications of this increased congestion, and of policies to offset it, like private healthcare subsidies.