Frequency and reliability have an impact on children’s reliance on cues for the segmentation and syntactic categorization of words. In German, the subsyllable “long vowel+consonant+/t/” reliably indicates that a word containing this type of subsyllable is an inflected verb form, e.g. “fehlt” (to lack, 3rd pers. sing.) or “wohnt” (to live, 3rd pers. sing.) In contrast, the more frequent subsyllable “short vowel+consonant+/t/” is not a reliable cue to word class as it occurs not only in inflected verb forms but in monomorphemic nouns and adjectives as well, e.g. “fällt” (to fall, 3rd pers. sing.), “Hemd” (shirt), “Feld” (field) or “rund” (round). This study addresses the question to what extent the different cue properties of subsyllables (i.e. reliability and frequency) have an impact on the processing of nouns, verbs and verb inflection. Participants of three different age groups were recruited: eighteen-month-old children, three- to five-year-old children with typical and atypical language acquisition and adults. Impacts of the different subsyllabic reliabilities and frequencies were found for all groups. This indicates that the subsyllable is a linguistic unit that provides relevant cues for early language acquisition and for language processing in adults. Therefore, it should also be considered for assessment and treatment of children with atypical language acquisition.