Out-of-school children (OOSC) has long been a global problem that affects a country in various ramifications. With 10.5 million OOSC, Nigeria is recognised to have the largest number of children not attending school in the world. The economic and social repercussions of not educating these children in Nigeria are examined in this brief. Exploratory data analysis and empirical estimation reveal the following facts:
• Economic costs due to OOSC in Nigeria is estimated to be about US$40 billion in modest terms.
• A higher number of rural dwelling children do not go to school as compared to the children living in the urban areas in Nigeria.
• Income poverty keeps more children out of school.
• The Northeast geo-political zone has the largest percentage of OOSC in Nigeria.