OBJECTIVE: Early-life socioeconomic factors, such as education, closely associated with the opportunity to become multilingual (ML), are important determinants of late-life cognition. To study the cognitive advantage of multilingualism, it is critical to disentangle whether cognitive benefit is driven by multilingualism or education. With rich linguistic diversity across all socioeconomic gradients, India provides an excellent setting to examine the role of multilingualism on cognition among individuals with and without education. METHOD: Using data from the Longitudinal Aging Study in India-Diagnostic Assessment of Dementia, we evaluated the association of multilingualism by language similarity (i.e., speaking languages from the same or different language families) and education with cognition. Longitudinal Aging Study in India-Diagnostic Assessment of Dementia is a nationally representative sample of older Indian adults aged 60 and over, speaking 40 different languages and dialects (N = 4,088, 54% without formal schooling). Multilingual participants were categorized whether they spoke ≥2 languages within the same (classified as ML1) or different (classified as ML2) language families. Participants completed a comprehensive cognitive assessment assessing the domains of executive functioning, language, memory, and visuospatial ability. RESULTS: Education stratified regression models adjusted for relevant covariates in the full sample and in a propensity-score matched sample. Among those with education, multilingualism was associated with better cognitive functioning across all domains regardless of language family (all p's <
.05). Among those without education, only ML1 (not ML2) was associated with better executive functioning (B = 0.17 [0.07, 0.27]) compared to monolinguals. CONCLUSIONS: These findings add to the growing literature on cognitive advantage of multilingualism, disentangling them from education and suggesting differential effects by language similarity. (PsycInfo Database Record (c) 2025 APA, all rights reserved).