The importance of small and medium-sized enterprises (SMEs) is widely recognised for the Slovenian economy. However, the issues regarding legislative and other administrative barriers and their perception by SMEs as a heterogeneous group of enterprises are not yet fully investigated. The main research hypothesis concerns that there exist significant differences in the perception of administrative barriers among characteristic SME groups. Consequently, this paper aims to provide a comprehensive analysis of the key administrative barriers SMEs face in Slovenia. This entails three activities: (1) identifying the main areas in which barriers are found; (2) establishing what they imply performance-wise; and (3) providing policymaker guidelines tailored to different SME groups (size, legal form, sector, age). The empirical results, based on one-way analysis of variance (ANOVA) and Bonferroni post hoc tests on a sample of 925 SMEs, show differences in the various groups of SMEs mentioned above. Thus, it is shown that it is most promising to address the administrative barriers through an in-depth approach that targets specific enterprise groups and is reflected within guidelines for responsible policymakers.