Neighborhood accessibility and availability of alcohol products has been associated with increased alcohol consumption and harms among adolescents. This availability has been shown to be higher in neighborhoods with lower socio-economic status (SES). The aim of this study was to examine inequalities in alcohol outlet density and proximity around schools by area-level SES in Madrid, Spain. Data on schools, SES, alcohol outlets and population density at census tract level were obtained through public databases from the local government of Madrid. We examined (1) density as the number of alcohol outlets around schools within 3 buffers (i.e. 200 m, 400 m and 800 m) and (2) proximity as the distance from schools to their nearest alcohol outlet. We performed multilevel analyses to examine the associations between alcohol outlet density and proximity and SES, adjusted by population density. Secondary schools (n = 576) located in less deprived areas had lower densities of alcohol outlets at walking distances of 200 and 400 m (50% and 37% lower, respectively p < 0.05). No significant differences were found for the proximity measures. The socioeconomic level of the area in which adolescents go to school is a determinant of their exposure to alcohol, where those who study in high SES areas have lower exposure to alcohol outlets. This study highlights the need to prioritize equity in the design and implementation of policies to limit alcohol accessibility among adolescents, including establishing minimum distances between schools and alcohol outlets or limiting the number of outlets per inhabitant in neighborhoods.