The introduction of corporate social responsibility (CSR) practices in small and medium-sized enterprises (SMEs) is important for the sustainable progress of the firm. To deepen this knowledge, we conducted a systematic review of the academic literature dedicated to CSR in SMEs, in order to substantiate relevant specifications. A rigorous approach to data collection was applied, considering only scientific journals in English and scientific papers published during the period 2003–2023 and using the SCOPUS database. With this information and the Biblioshiny tool from the Bibliometrix package of R Studio for data manipulation, we have been able to make a formal characterization of the selected documents. These findings have revealed a series of comprehensive studies that analyze the relationship between the adoption of CSR practices and business performance in small and medium-sized companies. From this analysis, it has been possible to discover a solid knowledge base about the current situation of the adoption of CSR practices in small and medium-sized companies, information that can be crucial to signal progress, future research points and areas that need to be thoroughly investigated. Future research is encouraged to address the development of new conceptions and perspectives that can contribute to improving both research and the actual adoption of CSR policies in small and medium-sized companies.