Purpose/Objective(s) Treatment options for localized renal cell carcinoma (RCC) include radical nephrectomy (RN), partial nephrectomy (PN), stereotactic body radiotherapy (SBRT), and ablative therapies (including microwave, cryo, thermal, radiofrequency). The goal of this work is to compare the effects of these treatments on kidney function, since kidney decline is primary driver of mortality for patients with localized RCC. Materials/Methods We conducted a systematic review study level meta-analysis, including publications from 2013 to 2023 using PICOS/PRISMA protocols and registered on PROSPERO, CRD42023428519. All patients had T1-3N0M0 RCC treated with RN, PN, SBRT, or an ablative therapy. Data extracted included cancer/patient characteristics, median-follow up, treatment modality, pre- and post-estimated glomerular filtration rate (eGFR), grade 3-5 toxicity, local control, and overall survival. Random effects regression models were used for comparative analyses. The primary objective was pre- and post-treatment eGFR, with 95% confidence intervals (95% CI), with the secondary objective being grade 3-5 toxicity events. Results A total of 42 studies reporting on 7,810 patients were selected for a quantitative analysis, including 11 evaluating SBRT, 12 evaluating ablative therapies, 17 evaluating PN, and 5 evaluating RN. Median follow up among all studies was 47 months. Median patient age was 65. Median tumor size was 3.4 cm. The pre vs post eGFR mean for RN was 21.8 (95% CI = 17.2, 26.3), for PN it was 5.5 (95% CI = 3.1, 7.9), for SBRT it was 8.6 (95% CI = 2.9, 14.3), and for ablative therapies it was 5.1 (95% CI = 2.2, 8.0). On meta-regression, statistically significant differences in eGFR were noted when comparing RN vs any other treatment (P < 0.0001); there were no significant differences when comparing ablation vs PN vs SBRT. SBRT was associated with significantly fewer Grade 3-5 toxicity events (0.2, 95% CI = [0; 1.1]) vs PN (4.7, 95% CI = [3.6; 6.0]; P = 0.003), and ablative therapies (4.3, 95% CI = [3.3; 5.4]; P = 0.0057). Conclusion For the treatment of localized RCC, SBRT, PN, and ablation are associated with the lower declines in eGFR when compared to RN. SABR had the fewest Grade 3-5 toxicities when compared to ablation, PN, or RN. These data can be used to facilitate informed discussions that compare potential benefits and risks for personalized, patient-centered care, as well as to power a clinical trial comparing treatments.