Ensuring access to water in adequate quantity and quality for human consumption at a fair and affordable price constitutes a supra-national commitment in the declaration of the human right to water and sanitation. In order to provide this service to society, financial resources are required to encourage new investment, maintenance and equipment replacement, adequate regulatory practices and a consistent legal framework. This article is based on a study of the affordability of water services by customers in the municipality of Santa Cruz, located on the island of Santiago in Cabo Verde, a country of high water stress and weak financial resources, in order to evaluate how socioeconomic conditions affect the realization of the human right to water. Data on socio-economic conditions, quality of services and affordability of clients was collected using survey tools, aiming to identify the need for differential treatment among consumers, requiring appropriate mechanisms of social solidarity to establish equity in access to services and, at the same time, ensure full cost recovery of services by the service provider.