OBJECTIVES: The cross sectional study aims to estimate the impact of socio-economic determinants, such as education and employment status, on the social cost of a patient with chronic kidney disease (CKD) stage IV and V pre-dialyses in Italy METHODS: Individual socio-economic and clinical data have been collected for all adult outpatients in charge of 14 main Hospitals Centers in Tuscany Region during 7 weeks between 2012 and 2013. Direct medical costs have been estimated using tariff for laboratory test, diagnostic exams, visits and hospitalization and price for drugs. The cost of diet, patients and caregivers travel expenses, formal and informal care have been evaluated as direct non medical costs. The human capital approach has been used for estimating the loss of productivity of patients and caregivers. The incremental effects of socio-economic determinants on social cost of CKD were estimated by multivariate Generalized Linear Models (log link, Gamma family) adjusting for gender, age and stage of disease. RESULTS: No qualification and low levels of educations and non-working status characterized, respectively, the 54% and 89% of 484 patients enrolled. The raw estimated mean annual social costs were €9,855 (± €6,826) per patient with CKD. Direct medical costs amounted to €4,352 (± 4,071), representing the 44% of the overall cost, while direct non medical costs and indirect costs accounted for 30% and 26% (€2.912 ± €3,823 and €2,590 ± €3,210). The incremental effect of non-working status on direct medical cost was €1.321 (95% CI: 121-2.520, p<0,05). Employment condition and high levels of education had an incremental effect on indirect costs of €2.616 (95% CI: 391-4.841, p<0,05) and €1.039 (95% CI: 135-1.943, p<0,05).   CONCLUSIONS: Socio-economic inequalities lead to a significant increase of direct medical cost of CKD. High education and employment status of patients significantly increase the indirect cost component of CKD social cost.