Background: Current literature mainly focuses on adaptive profiles from a categorical perspective but yields inconclusive results. The present study puts a transdiagnostic approach next to a "classical" categorical approach. Methods: In this study, 222 children (5-18 years old) with autism and/or intellectual disability participated. Variance analyses, based on standard scores from ABAS-3 at group-level, were conducted in order to compare adaptive domains within categories. A K-Means cluster analysis was used to delineate empirically derived clusters with a similar profile of difference scores at an individual level. Chi-square tests and variance analyses were used to investigate the distribution of variables across clusters. Results: From a categorical perspective, results were in line with current literature. A transdiagnostic perspective revealed three adaptive profiles (Homogeneous, Social, and Practical). No perfect match was found between specific adaptive profiles and diagnostic categories. Conclusions: A transdiagnostic perspective sheds light on the heterogeneity within and the overlap across diagnostic categories.