The existing literature reports no clear patterns for the influence of extralinguistic variables on MSs because they vary across languages. Therefore, the current study addresses this issue by analyzing the development of MSs at the beginning of formal schooling and by determining the extent to which demographic variables affect metalinguistic development in normally developing European-Portuguese (EP) children. The sample included 80 EP first graders aged 6;00-6;11 years who presented a normal linguistic development. The Language Test - Preschool Language Assessment (TL-ALPE) was used to assess MSs in the domains of semantic, structural, and phonological awareness. At the beginning of formal schooling, only one phonological awareness task involving syllables was considered to be acquired and established among all metalinguistic tasks elicited. Significant group differences were not found for the demographic variables of gender, socioeconomic status, and ecological setting. These findings contribute to the increasing literature on MSs. The reference information provided is important for accurately identifying school-aged children with language impairment.