OBJECTIVES: The number of prevalent patients with end-stage renal disease (ESRD) in Greece has grown nearly 13% since 2003. Approximately 83% of prevalent ESRD patients are on dialysis, the rest have a functioning kidney transplant. For ESRD patients needing dialysis, two treatment options are available, hemodialysis (HD) and peritoneal dialysis (PD). Both have been shown to have similar outcomes yet most (91%) dialysis patients in Greece receive HD. The objective of this evaluation is to project a five-year impact on total direct dialysis costs if utilization of the less expensive equally, effective PD were increased to 15% of all dialysis. METHODS: An Excel-based budget impact model was used to estimate the impact of a shift in modality utilization. The model takes into account dialysis modality shares, annual average cost of treating patients per modality, annual ESRD growth rate, patient years at risk and years to reach new dialysis modality distribution. Cost data from a recent Greek study were used. At baseline (2007) there were 8189 patients undergoing dialysis therapy, 91% using HD and 9% using PD. Annual direct cost per patient were €36,247 for in-center HD and €30,719 for PD. We applied a 2% annual ESRD growth rate; set the target PD modality share at 15%, and that this target would be achieved in the fifth year. Total costs included equipment/infrastructure, diagnostic services, drugs and consumables, staff salaries, and operational costs/overheads. RESULTS:  If PD utilization gradually increases to 15% by 2012, the cumulative 5-year cost would be reduced by €6.5 million. Alternatively, the savings could provide an additional 258 patient-years of dialysis treatment. CONCLUSIONS: In Greece, an increased use of PD can reduce the direct costs of dialysis treatment which then provides an opportunity to use scarce health care resources on other pressing needs.