The revised EU Renewable Energy Directive first introduced renewable energy communities into the EU policy framework and requires Member States to implement a support framework for them. Given the broad scientific evidence showing the benefits of community energy for a just energy transition, a successful implementation across all Member States is essential. However, the preconditions for developing support frameworks differ largely between EU nations, as some countries have long-term experiences with supporting renewable energy communities (i.e., Germany and Denmark), while in other Member States, renewable energy communities are notably non-existent (i.e., Eastern European nations). With the purpose of providing scientific evidence to support the development of a policy framework for renewable energy communities in Eastern European Member States, this article compares key factors for the development of such communities in Bulgaria and Germany, combining a literature review with expert interviews to collect primary information on Bulgaria. A country analysis puts these factors into the contexts of both countries, while a cross-country comparison demonstrates that there are significant gaps in the support framework of Bulgaria, although these gaps are, to a lesser extent, also present in Germany. We discuss these shortcomings, derive policy recommendations and identify further research needs.