Tuition-free primary education has been available in Uganda for over a decade, but universal enrollment has yet to be attained, as the Net Enrollment Ratio (NER) stands at 83%. In this paper, we analyze this issue using household survey and institutional administrative data. We find that the Ugandan primary school education experience is characterized by, among other issues, over-age enrollment and elevated attrition rates. Indeed, research has shown that the median survival in primary school is less than five years. Socioeconomic status, geographic location of the school, age at initial enrollment, and child labor (but not child gender) are some of the factors that contribute to school non-attendance and dropout rates. Child labor is particularly countervailing and this paper highlights that a differentiation exists between urban and rural areas. In urban areas, children who work are more likely to attend school, in rural areas they are less likely. We highlight attrition as an area that warrants specific policy attention.