BACKGROUND: Little data are available for infants who started renal replacement therapy before 6 months of age. Because of extra-renal comorbidities and uncertain outcomes, whether renal replacement therapy in neonates is justified remains debatable. METHODS: We performed a retrospective analysis of all patients who began chronic peritoneal dialysis below 6 months between 2007 and 2017 in two tertiary centres. Results are presented as median (min;max). RESULTS: Seventeen patients (10 boys) were included (8 prenatal diagnoses, 6 premies), with the following diagnoses: congenital anomalies of kidney and urinary tract (n=9), oxalosis (n=5), congenital nephrotic syndrome (n=2) and renal vein thrombosis (n=1). Five patients had associated comorbidities. At peritoneal dialysis initiation, age was 2.6 (0.1;5.9) months, height-standard deviation score (SDS) -1.3 (-5.7;1.6) and weight-SDS -1.4 (-3.6;0.6). Peritoneal dialysis duration was 12 (2;32) months, and at peritoneal dialysis discontinuation height-SDS was -1.0 (-4.3;0.7) weight-SDS -0.7 (-3.2;0.2), parathyroid hormone 123 (44;1540) ng/L, and hemoglobin 110 (73;174) g/L. During the first 6 months of peritoneal dialysis, the median time of hospitalisation stay was 69 (15;182) days. Ten patients presented a total of 27 peritonitis episodes. Reasons for peritoneal dialysis discontinuation were switch to hemodialysis (n=6), transplantation (n=6), recovery of renal function (n=2) and death (n=1). After a follow-up of 4.3 (1.7;10.3) years, 12 patients were transplanted, 2 patients were still on peritoneal dialysis, 2 patients were dialysis free with severe chronic kidney disease and 1 patient had died. Seven patients displayed neurodevelopmental delay, of whom five needed special schooling. CONCLUSION: We confirm that most infants starting peritoneal dialysis before 6 months of age will be successfully transplanted and will have a favourable growth outcome. Their quality of life will be impacted by recurrent hospitalisations and neurodevelopmental delay is frequent.