In Russia, an industry specific national project approved the “creation of an acceleration system for small and medium-sized businesses” task for implementation. The limitations of the implemented federal project “Acceleration of small and medium-sized businesses” are revealed: they consist in the vagueness of the formulated approach to the disclosure of the essence of the acceleration process itself. A review of Russian and foreign sources has shown that in the generalized scientific approach, the main purpose and specificity of acceleration is a complex of intensively provided services for the development, verification and scaling of projects into ready-to-invest businesses. The scientific problem lies in the presence of numerous provisions on the specifics of acceleration, but the absence of a comprehensive and consistent list of its distinctive features. The purpose of the study is to generalize, expand and classify the system of distinctive features of acceleration and the specificity of their services that are not taken into account in the federal project. The methods of analysis and synthesis, content analysis and generalization were used in the study. The information basis for the analysis included foreign (Web of Science databases) and Russian (RSCI database) publications over the past 10 years, relevant domestic regulatory and legal documents. As a result, the existing varieties of accelerators are systematized according to the following parameters: the economic goal to be solved, sources of financing, target audience and their stage of development. The system of distinctive signs of acceleration is generalized, expanded and classified. The novelty of this approach lies in the development of the missing extended list of distinctive features of acceleration. They are classified according to the criteria of specificity and frequency of occurrence, taking into account their representation in strategic legislation. The scientific and practical significance lies in the opportunity to better understand the meaning of acceleration services, its advantages, limitations, and contribute to solving the problem of the complexity of the implementation of acceleration services in the federal project. The continuation of the study will focus on empirical verification of the actual presence and prevalence of classified features in Russian accelerators. It also requires a subsequent assessment of the contribution of acceleration services to the support system of business structures.