Sevelamer hydrochloride (HCl), a calcium-free phosphate binder, is increasingly used due to concerns related to calcium exposure and the development of vascular calcifications. However, a common side effect of sevelamer HCl, metabolic acidosis, is particularly concerning in children, as it can contribute to poor growth. Sevelamer carbonate is now available and has been shown to increase serum bicarbonate in adult patients. We conducted a prospective single-center study of pediatric dialysis patients comparing serum bicarbonate before and 3Β months after a switch from sevelamer HCl to sevelamer carbonate. Inclusion criteria were a minimum of 3Β months of dialysis therapy and either a serum bicarbonate <20Β mmol/L or the need for sodium bicarbonate supplementation. Ten hemodialysis and 14 peritoneal dialysis patients, aged 16βΒ±β3Β years, were enrolled. Whereas serum calcium and phosphorus remained unchanged, serum bicarbonate increased from 20 (17.2β22.0) to 24.5 (20.75β26) mmol/L (pβ<β0.001) after 3Β months of sevelamer carbonate therapy. Sodium bicarbonate supplementation was stopped in all patients (nβ=β10), reducing the mean daily sodium intake by an average of 2.3 g per patient. These results demonstrate that sevelamer carbonate is an effective phosphate binder that improves acid-base status in pediatric dialysis patients.