PURPOSE: To create a succinct yet comprehensive evidence-based structured report template for indeterminate renal masses characterized at CT and MRI. METHODS: This IRB-exempt, iterative, multi-institutional quality improvement project was informed by published data derived from a multi-institutional survey and a multi-institutional review of CT and MRI radiology reports. A two-stage blinded Delphi process by the 16-member 12-institution Society of Abdominal Radiology Disease-Focused Panel on Renal Cell Carcinoma was conducted to create a structured report template for indeterminate renal masses evaluated at CT and MRI. Individual reporting characteristics were scored by members as core, optional, or exclude. Threshold for inclusion was ≥ 80% support. If < 80% members considered a characteristic a core feature, but ≥ 80% considered it either core or optional, it was considered an optional feature. If neither was the case, the characteristic was excluded. Free-text comments were permitted. Characteristics considered core by 50-99% of respondents in Round 1 (i.e., nonunanimous support) and uninvestigated free-text comments were assessed in Round 2. Core and optional structured reporting templates were derived. RESULTS: The response rate was 100% in Round 1 (16/16) and Round 2 (16/16). In Round 1, 5 characteristics had unanimous support as core features. Following Round 2, 13 characteristics had ≥ 80% support as core features, and 10 characteristics had ≥ 80% support as optional features. Structured report templates were derived. DISCUSSION: Structured core and optional templates for indeterminate renal masses at CT and MRI were derived, which may improve compliance with reporting preferred and essential imaging characteristics.