Introduction: Contemporary data regarding the effect of age, especially in elderly patients, on cancer-specific mortality (CSM) for pT1a renal cell carcinoma (RCC) are lacking. The objective of the current study is to evaluate CSM in a large population-based cohort of surgically treated pT1a RCC patients according to age groups.Methods: Within the Surveillance Epidemiology and End Results database (2000‒2013), we identified 37 121 pT1a RCC patients who underwent either partial or radical nephrectomy. The population was stratified into five groups according to decades: <50, 50‒59, 60‒69, 70‒79, and ≥80 years. The effect of age on CSM was evaluated using competing risks regression models according to Fuhrman grade (FG). Analyses were repeated in clear-cell RCC (ccRCC).Results: Patients aged 50‒59 (9615), 60‒69 (10 762), 70‒79 (7096), and ≥80 (1789) years demonstrated higher rate of CSM compared to patients aged <50 (7856) years (hazard ratios [HR] 2.11, 3.04, 4.47, and 7.56, respectively; all p<0.001). The effect of age on CSM in FG 1‒2 patients resulted in HRs ranging from 2.01‒8.23 for the same age decades (all p< 0.001). Similarly, the effect of age on CSM in FG 3‒4 patients resulted in HRs ranging from 2.38‒5.92, respectively (all p<0.001). Virtually the same results were recorded in ccRCC patients.Conclusions: Older age is associated with higher CSM in surgically treated patients with pT1a RCC. This effect seems to be more pronounced in patient with FG 1‒2 disease. This observation should be considered when making treatment decisions in elderly patients.