This study aims to begin accounting for variation in parents' perceptions concerning CLIL at a particular context by focusing on a major component of socioeconomic status: education level. The study is set in Andalusia, a Spanish region with an ongoing bilingual CLIL programme that, according to official estimates, will reach 1,573 schools by 2020. A questionnaire was designed to obtain information on perceptions about the teaching and learning of Natural Science and Social Sciences in English. A total of 200 parents from three primary schools participated in the study. Findings indicate that educational attainment has a differential effect on parents' perceptions on the bilingual programme, on its impact on student learning, on their own capacity to help their children's school learning and on children's need for out-of-school support. The lowest educated parents are the most satisfied with the programme and the least concerned about its potential detrimental effect on content learning even though they find that their children are struggling in English-taught subjects the most. Findings suggest that this group in particular may associate English with upward social mobility more strongly than the others. Implications of findings concerning egalitarianism in CLIL education are also discussed.