Purpose: Using longitudinal data of children in Nepal, this study examines the relationships between dropouts, grade repetition and the causes of dropout, such as entrance age, to derive concrete recommendations to improve the basic education completion rates in Nepal, one of the targets of Sustainable Development Goal 4 (SDG4). Design/methodology/approach: The data for this study were drawn from school records kept in the target schools, home visit surveys and interviews with principals and teachers. After comparing the repetition experience and the frequency of repetitions between graduates and dropouts, the study analysed the dropout patterns of individual children. The study then examined the effects of repetition and entrance age on children's schooling. Findings: The results identified a large group of children who dropped out of school without any repetition, with only 15.9% of the children repeating a grade immediately before dropping out. The findings indicated that harsh family environments, being overage and low educational expectations were factors in sudden dropout. Originality/value: Collecting longitudinal data is difficult in developing countries, and few studies use such data. The question of access to education has been re-ignited by the COVID-19 pandemic; this study used longitudinal data to thoroughly analyse children's dropout patterns and provide specific recommendations that will contribute to the achievement of SDG4.