Positive surgical margins (PSM) for solid organ malignancies are associated with adverse oncological outcomes. However, for RCC the prognostic significance of PSM after partial nephrectomies (PN) remains a matter of debate. As PN is more increasingly being used to excise larger and more complex renal masses (RM), PSM status could become of paramount significance in this group of patients. The authors evaluated data for 1240 cases of T1 and T2 RM, who had undergone PNs between 2006-2013 at four major centres in the USA. Postoperatively patients were divided into two pathological sub-groups: low-risk (pT1 and Fuhrman grade I-II) and high-risk (pT2-3 and / or Fuhrman grade III-IV). The relationship between PSM status and the risk of relapse was evaluated for the two pathological sub-groups. A total of 97 (7.8%) PSMs were observed, of which 69 (71.1%) were in low-risk and 28 (28.9%) were in high-risk group. During a median follow-up of 33 months, 69 (5.6%) recurrences were noted at a median time of 19 months. Out of these 69, local recurrences were 42 (60.9%) and metastases in 27 (39.1%) cases. Increased tumour size, higher grade and stage, and clear cell histology was associated with increased recurrence risk. While PSM was associated with increased recurrence risk it was not found to be predictive of recurrence site. Based on pathological sub-grouping, patients with a low-risk PSM had recurrence free survival (RFS) similar to those with low-risk negative surgical margins (NSM). High-risk groups with a PSM were found to have a higher risk of recurrence (almost 45% in five years), compared to high-risk NSM as well as both PSMs and NSMs low-risk groups. The authors conclude that high-risk cases (described as above) with PSM, should have more intensive follow-up schemes to help timely detection of recurrence. Further studies are also recommended to assess the oncological outcomes of early completion nephrectomy in this group.