This paper discusses how to measure whether and to what degree EU environmental policy is socially just by using easily interpretable indicators. Its main task is to assess existing (or officially discussed) European-level indicators at the socio-environmental nexus on their suitability to serve as Just Transition (headline) indicators, and to identify gaps. The paper focuses on social justice within Europe and looks at three broad socio-environmental issue areas: • Environmental benefits, pollution & risks • Consumption- and social-participation opportunities for vulnerable groups • Employment & regional cohesion (as affected by environmental policies/transitions). The paper builds on the diversity of social effects of environmental policy and reveals a broad range of existing European indicators to monitor certain aspects of them. Given the variety of effects, it seems impossible to define a single ‘perfect’ Just Transition indicator. Monitoring a Just Transition from an environmental-policy perspective needs a combination of indicators from different issue areas. Moreover, many indicators need to be developed further to serve as Just Transition indicators. Suggestions (from short-term to long-term) for improving indicators and closing gaps are made in this paper, with reference to some national-level good practices. In addition to single-number indicators, in-depth analyses are also necessary on many issues. The suggestions put forward should be taken as a starting point for further discussion.