This study evaluates the ability of different measures of socioeconomic status (SES) to predict lexical outcomes for preschoolers raised in a context of nationwide bilingualism. The participants were 58 children aged 3;11-4;3 from Maltese-dominant homes who attended state preschools. Receptive picture name judgement and picture naming, in Maltese and English, were employed to measure receptive and expressive lexical abilities, respectively. Lexical outcomes for four individual SES variables and a single composite SES measure were similar but not directly interchangeable. The composite SES variable emerged as most strongly predictive of children's lexical performance. Receptive judgement of phonological accuracy improved similarly in both languages with higher composite SES. Naming skills increased significantly in English but not in Maltese, suggesting differences in English input related to parental SES. A focus on SES in relation to lexical skills in two majority languages is novel and adds to current understanding of normative bilingual acquisition.