OBJECTIVES: ESRD patient survival is similar for hemodialysis (HD) and peritoneal dialysis (PD). In Brazil, access to dialysis is universal, although the resources consumed and their costs are poorly understood. We compare the resources used for the treatment of patients undergoing HD or PD who are covered by public insurance. METHODS: A one-year prospective study comparing resource use and total costs of prevalent patients treated with HD (n=210) and PD (n=194) was conducted in 5 dialysis units in Sao Paulo, Brazil. Inclusion criteria: ≥18 years of age and clinically stable on chronic dialysis. The study period was April 2007 to February 2009. Data were obtained at baseline, 6 and 12 months using surveys and medical records. Cost categories included hospitalizations, diagnostic and therapeutic procedures, medications, professional fees, transportation, and lost productivity (current homemakers who stopped working due to dialysis). Government reimbursement rate was used as a proxy for the direct costs related to the act of dialysis (maintenance). The study took the societal perspective. RESULTS: Approximately 50% of HD and 48% of PD patients were female (p=0.75); 54% and 58% were white (p=0.48); mean age was 55.2 and 60.6 (p<0.001); 62% and 71% had diabetes (p=0.0528); and 59% and 55% had coronary heart disease (p=0.37), respectively for HD and PD. Overall average costs per patient-year of follow up was US$23,283 for HD and US$23,285 for PD patients. The average annual cost per patient-year, per category, for HD and PD were respectively, US$11,774 and US$14,058 for maintenance dialysis costs; US$9,208 and US$7,559 for medications; US$94 and US$43 for hospitalization, US$796 and US$487 for travel costs and $US323 and $264 for current homemakers lost income due to dialysis. CONCLUSIONS: Mean annual total cost of PD and HD are nearly identical, even though the former were significantly older and more diabetic.