Hyperkalemia is a known complication of chronic kidney disease (CKD); however, it is not known whether hyperkalemia directly contributes to CKD progression and the risk of death. Clarifying the extent to which hyperkalemia is associated with CKD progression and mortality can inform clinical practice and guide future research. The objective of this study was to quantify the risks of CKD progression and mortality associated with hyperkalemia in patients with stages 3b/4 CKD.