Reducing physical contact has been the most common strategy adopted by governments to reduce the spread of the COVID-19 disease. It has led most countries to close their schools. Previous evidence on the effects of teacher strikes, summer holidays, armed conflicts or any other cause of school closure on learning suggest that the effects of COVID-19 will be highly significant for some and will vary depending on students' previous performance, family characteristics, age or education track, among other factors. Recent evidence shows that learning losses during school closures have been widespread and especially intense among the more disadvantaged students. In this article we evaluate the magnitude of the gap regarding opportunities to learn in formal, informal and non-formal education between families depending on their cultural and economic capital. An online survey (n = 35,937) was carried out during the second week of the confinement (March 2020) in Catalonia. The survey targeted families with children between three and eighteen years. The responses show remarkable social inequalities in opportunities to learn. In this article, we describe the magnitude of the learning gap between social groups and explore which are the most significant factors that explain educational inequalities. Our findings reveal a process of cumulative disadvantage that results from unequal opportunities in formal, informal and non-formal education and underline the need to address both school and family factors to mitigate the impact of the pandemic on learning opportunities.