The recent intersection of two entrepreneurship streams – technology and social – has given rise to the emergence of technology-based social enterprises (TSEs). TSEs are of particular interest to many stakeholders as they have the potential to provide scalable solutions from a technological perspective to address diverse social challenges in the world. However, a review of the literature revealed a gap in knowledge on the growth process of TSEs because: (1) TSEs are an emerging phenomenon; (2) existing research on technology enterprises has predominantly focused on issues related to profit and value maximization; (3) existing research on social enterprises and non-profits typically do not have a technology focus. To address the gap in knowledge, in-depth case studies were conducted on five prominent TSEs based in Cambridge, United Kingdom – Raspberry Pi, Simprints, WaterScope, Solaware, and Blue Tap. The case studies were conducted in two stages – Stage 1 was structured around an initial resource-based conceptual framework derived from the literature; Stage 2 was structured around a legitimacy-based framework derived from literature. Findings from Stage 1 revealed the similarities and differences of growth between TSEs and commercial technology enterprises or traditional non-profits. The findings from Stage 1 also indicated that legitimacy as a resource has significance for the growth of TSEs, which led to the implementation of the legitimacy-based Stage 2 to provide further analysis. The findings from both stages were subsequently used to modify and enhance the initial resource-based conceptual framework. This study provides contributions to theory through the development of a conceptual framework to describe the growth process of TSEs. The study also revealed the strategic use of legitimacy as a resource by TSEs to grow. This study also contributes to practice by providing empirical findings on the resource acquisition process of TSEs. The findings highlight the importance of specific resources accessible by TSEs, such as the use of skill-based volunteers and pro bono resources, which are unconventional to both commercial technology-based enterprises and traditional non-profits. The study also revealed that the environment plays a crucial role in facilitating resource acquisition by TSEs. An environment such as Cambridge that has a rich ecosystem of individuals and organizations to support technology-based organizations has been found to be conducive for the growth of TSEs.