Background/Objectives: Robot-assisted partial nephrectomy (RAPN) has increasingly replaced laparoscopic partial nephrectomy (LPN) in the management of localized renal tumours. This study aimed to evaluate perioperative, functional and surgical margin outcomes during an institutional transition from LPN to RAPN in a high-volume centre. Methods: We performed a retrospective single-centre analysis of 100 consecutive patients undergoing minimally invasive partial nephrectomy. The last 50 LPN cases (August 2014–May 2018) were compared with the first 50 RAPN cases (June 2018–February 2020). Baseline characteristics, perioperative outcomes, early functional parameters and surgical margin status were analysed. Complications were classified according to the Clavien–Dindo system. Results: Tumours treated in the RAPN group were significantly larger (3.4 vs. 2.5 cm) and more complex (RENAL score of 6 vs. 5; p < 0.001). Operative time was longer in the RAPN group (143 vs. 122 min; p < 0.01), while warm ischaemia time did not differ significantly (16 vs. 15 min; p = 0.37). Estimated blood loss was lower (0 vs. 10 mL; p = 0.049) and the hospital stay was shorter (3 vs. 4 days; p < 0.001) in the RAPN group. Haemoglobin decrease and postoperative creatinine change were comparable between groups. Positive surgical margins were observed less frequently in the RAPN group (2.3% vs. 7.7%), but this difference was not statistically significant (p = 0.34). Complication rates were significantly lower in the RAPN group (4% vs. 22%; p < 0.05), with no major complications observed in the robotic cohort. Conclusions: In this institutional experience, RAPN was associated with favourable perioperative outcomes during the transition period, despite the treatment of larger and more complex renal tumours. The slightly longer operative and warm ischaemia times likely reflect a more comprehensive reconstruction strategy, which may contribute to improved haemostatic control and lower complication rates. Further studies with extended follow-up are required to evaluate oncological and renal functional outcomes.