To compare the operative and functional result of partial and radical nephrectomy in renal cell carcinomas of stages pT2-3a. Consecutive patients with renal cell carcinoma of stages pT2-3a, cN0 and cM0, who underwent partial or radical nephrectomy between January 2005 and October 2019 at a tertiary care center were included. Data were collected retrospectively. End-points included severe postoperative complications (Clavien-Dindo classification ≥3), acute and chronic renal function impairment, and overall survival. Uni- and multivariable outcome analyses were based on logistic regression. A total of 158 patients were included (110 radical nephrectomy and 48 partial nephrectomy). Over time, partial nephrectomy was increasingly used. A RENAL score ≥10 was the only independent predictor influencing the surgical approach (radical nephrectomy vs partial nephrectomy, odds ratio 8.62, 95% confidence interval 3.32-22.37, P < 0.001). No significant differences in complications for radical nephrectomy versus partial nephrectomy were found (12.7% vs 8.3%, P = 0.424). Renal function was better preserved in the partial nephrectomy group (the latest chronic kidney disease stage ≥3: radical nephrectomy 73% vs partial nephrectomy 41%, P = 0.005). The surgical approach was a significant factor for chronic kidney disease (odds ratio 51.07, 95% confidence interval 3.57-730.59, P = 0.004). Overall survival did not significantly differ between radical nephrectomy and partial nephrectomy (mean overall survival 85.86 months, 95% confidence interval 3.83-78.36 vs 81.28 months, 95% confidence interval 4.59-72.29, P = 0.702). In selected patients, partial nephrectomy can be used in large or locally advanced renal cell carcinoma. Compared with radical nephrectomy, it allows better preservation of renal function without harboring an increased risk of severe postoperative complications. © 2020 The Japanese Urological Association.