Policymakers and scientists regard emerging circular initiatives as levers for transformations towards more sustainable food systems. However, it remains unclear how to determine the extent to which circular initiatives have transformative potential. That is, can these initiatives foster a transformation as a result of how they currently bring circularity into practice? In the transformation literature, the characteristics of transformative initiatives are conceptualised in a generic and abstract way. To address this gap, we develop a heuristic of five characteristics for potentially transformative circular agriculture initiatives, which we illustrate with examples of existing initiatives. The heuristic builds on the 'small wins' and circular agriculture literature. Initiatives that hold transformative potential contribute to circular agriculture principles with outcomes that are concrete, in-depth and both technological and social in nature. Additionally, these initiatives faced barriers and overcame them. The heuristic enables policymakers, who call for circular solutions, to identify truly transformative circular initiatives.