Photovoltaic citizen participation initiatives (CPIs) receive increasing attention as a form of social innovation, contributing to a sustainable decentralized energy future. However, their ability to outgrow a protected niche characterized by feed-in tariffs, to regime level, is unclear. Drawing on qualitative interviews with key actors, the present study classifies Austrian CPIs in terms of them being market-based (profit-oriented business) or grassroots initiatives (civil-society based community activism), and compares these two types with respect to the three key processes of strategic niche management: actor network formation, learning, and expectations management. Market-based CPIs exhibit a relatively heterogeneous external actor network. They follow a policy of business development, engage in highly professionalized learning, and access a large, widespread customer base. In contrast, grassroots CPIs leverage a tightly-knit network of local actors, engage in informal learning and shared expectations. In some CPIs, market-based and grassroots motivations converge. Both types seem capable of achieving regime level, either through individual growth or by aggregation of multiple small-scale initiatives. As yet, few CPIs have outgrown their local niche status. This is mainly due to a lack of intermediary actors which may institutionalize knowledge and resources to support the foundation of new CPIs.