ABSTRACT Hypothesis: Partial Nephrectomy is oncological safe in patients with pT3a RCC. Purpose: To compare the oncological and functional outcomes of patients with pT3a RCC scheduled for PN and RN. Materials and Methods: We retrospectively reviewed patients with pT3a N0 M0 RCC who underwent partial or radical nephrectomy from 2005 to 2016. Perioperative characteristics, including estimated glomerular filtration rate, tumor size, pathological histology, and RENAL nephrometry score, were compared between patients scheduled for partial or radical nephrectomy. We used multivariable Cox proportional hazards regression models to compare overall survival, cancer-specific survival, and recurrence-free survival between planned procedure type. Results: Of the 589 patients, 369 (63%) and 220 (37%) were scheduled for radical and partial nephrectomy, respectively; 26 (12%) of the scheduled partial nephrectomy cases were intraoperatively converted to radical nephrectomy. After adjusting for tumor size and histology, there were no statistically significant differences in overall survival (hazard ratio 0.66; 95% CI, 0.38–1.13), cancer-specific survival (hazard ratio 0.53; 95% CI, 0.16–1.75), or recurrence-free survival (hazard ratio 0.66; 95% CI, 0.34–1.28) between patients scheduled for partial or radical nephrectomy. Fewer patients scheduled for partial nephrectomy had estimated glomerular filtration rate reductions 3 to 9 months after surgery than patients scheduled for radical nephrectomy. Conclusion: We found no evidence that patients scheduled to undergo partial nephrectomy had poorer oncologic outcomes than patients scheduled to undergo radical nephrectomy. In select patients with pT3a renal cell carcinoma in whom partial nephrectomy is deemed feasible by the surgeon, partial nephrectomy should not be discouraged.