With the publication of DSM-5, many changes were introduced regarding how Autism Spectrum Disorder (ASD) would be diagnosed. Changes from DSM-IV-TR were controversial, with many arguing that individuals would lose their diagnosis with the new criteria. The purpose of this study was to examine differences in the application of diagnostic criteria across both recent versions in a sample of infants and toddlers. Fewer individuals met criteria according to DSM-5; however, a larger proportion of individuals met criteria for both. Additionally, individuals with higher levels of symptoms were more likely to meet criteria for both versions as compared to either alone. Overall, results suggest that there are meaningful differences in how DSM criteria may apply to individuals with an ASD.