Vascular calcification is a frequent complication of advanced chronic kidney disease. Protein carbamylation is implicated in the acceleration of vascular disease in chronic kidney disease, but the mechanisms are not clear. Mori et al. report that protein carbamylation exacerbates vascular calcification by decreasing ectonucleotide pyrophosphate/phosphodiesterase 1 expression, owing to carbamylation of mitochondrial proteins and oxidative stress. This provides new insight into the pathways responsible for calcification in chronic kidney disease.