OBJECTIVE To investigate whether oral health literacy (OHL) and school context are associated with untreated dental caries on the anterior teeth of adolescents. METHODS A representative cross-sectional study was conducted with 746 students aging 15 to 19 in the city of Campina Grande, Brazil. The guardians answered a questionnaire addressing sociodemographic data and the absence/presence of private health insurance. Two examiners were trained for the diagnosis of dental caries using the Nyvad criteria and the measurement of OHL using the Brazilian Rapid Estimate of Adult Literacy in Dentistry (BREALD-30) (Kappa > 0.80). Contextual aspects of the schools were obtained from the 2017 National School Census. Descriptive statistics were conducted, followed by unadjusted and adjusted robust negative binomial regression for complex samples (p < 0.05). RESULTS The average number of anterior teeth with untreated caries was 0.95 (SD = 1.77). Among individual factors, the male sex (RR = 1.64; 95%CI: 1.24–2.16), inadequate level of OHL (RR = 2.03; 95%CI: 1.13–1.63), marginal level of OHL (RR = 1.87; 95%CI: 1.05–3.33) and not having private health insurance (RR = 1.34; 95%CI: 1.07–1.68) were associated with untreated caries on anterior teeth. Among school contextual factors, the number of students in the classroom (RR = 2.64; 95%CI: 1.78–3.93), number of public oral health services in the district (RR = 0.14; 95%CI: 0.05–0.39) and average income of the district in which the school is located (RR = 0.99; 95%CI: 0.98–0.99) were associated with the outcome. CONCLUSIONS Sociodemographic factors, having private health insurance, OHL, and school context exerted an influence on the occurrence of untreated dental caries on anterior teeth in adolescents aging 15 to 19.