This article addresses the legal and ethical uncertainties surrounding the use of administrative data for research. Drawing upon best practices developed by the authors in previous data initiatives and engagement with research communities, the article suggests a problematic organizational culture as the most significant barrier to proportionate and good governance of administrative data. Accordingly, it offers a novel means for data custodians to identify key considerations by introducing a decision‐making template that supports public authorities' assessment of preparedness for data reuse through identification of challenges faced, related to sector‐specific practices. As a catalyst for change, the authors advocate a public interest mandate – commitment to safely and ethically use administrative data when it is in the public interest to do so. This is delivered through implementation of the decision‐making template, overt commitment to principles of public interest and proportionality, and engagement with stakeholders to address remaining areas of uncertainty.