Lifelong therapy with mineralocorticoid receptor antagonists (MRAs) or surgical adrenalectomy are the recommended treatments for primary aldosteronism (PA). Whether these treatments mitigate the risk for kidney disease remains unknown. We performed a retrospective cohort study of patients with PA treated with MRAs (N=400) or surgical adrenalectomy (N=120) and age- and estimated glomerular filtration rate–matched patients with essential hypertension (N=15 474) to determine risk for chronic kidney disease and longitudinal estimated glomerular filtration rate decline. Despite similar blood pressures, patients with PA treated with MRAs had a higher risk for incident chronic kidney disease compared with essential hypertension patients (adjusted hazard ratio, 1.63; 95% confidence interval, 1.33–1.99). Correspondingly, the adjusted annual decline in estimated glomerular filtration rate was greater in PA patients treated with MRAs compared with essential hypertension patients (−1.6; 95% confidence interval, −1.4 to −1.8 versus −0.9; 95% confidence interval, −0.9 to −1.0 mL/min per 1.73 m2/y; P<0.001). In contrast, patients with unilateral PA treated with surgical adrenalectomy had no significant difference in risk for incident chronic kidney disease or in an annual decline in estimated glomerular filtration rate compared with essential hypertension patients. Among PA patients with diabetes mellitus treated with MRAs, there was a higher risk for incident albuminuria compared with essential hypertension (adjusted hazard ratio, 2.52; 95% confidence interval, 1.28–4.96). MRA therapy in PA is associated with higher risk for developing chronic kidney disease when compared with essential hypertension, and surgical adrenalectomy may mitigate this risk. When possible, curative surgical adrenalectomy may be superior to lifelong MRA therapy in preventing kidney disease in PA.