A key goal of many digital or e-participation pilot projects is to scale and institutionalize the project within the host administration, but also to replicate the project across an entire country or region. Whilst there is broad understanding of how the diffusion of e-participation innovations takes place, there are gaps in our knowledge about how implementation approach and technology characteristics shape scaling and replication across contexts, how institutionalization processes interact across intra-municipal, inter-municipal and macro levels, and what skills and capabilities researcher-intermediaries require to support these processes. To address these gaps, the paper draws on a body of research focused on ‘Transformative Innovation Policy’ (TIP) which provides lower-level insights on the expansion and mainstreaming of public interest innovations, such as e-participation. We first use TIP as a conceptual lens to develop an expanded conceptual map of potential institutionalization mechanisms through a review of existing e-participation literature. We then use the mapping to evaluate our own action-research process in which the coauthors facilitated replication and scaling actions around eight e-participation pilot projects in South Africa. Amongst others, the findings show how a user-driven and ‘low-tech’implementation approach can enable initial scaling and institutionalization amongst key stakeholders within municipalities, and flexible learning and transfer of practices between municipalities. However, this approach affected the involvement of some traditional technology actors, such as municipality IT departments, with implications for longer-term sustainability and institutionalization. In addition, the results highlighted specific skills and capabilities that are critical for intermediaries or facilitators of similar technology and innovation scaling, replication and institutionalization processes in the public sector.