Purpose: Against the backdrop of falling standards and failing government policies in the education sector in Nigeria, this paper aimed to investigate how and why non-state actors can make a significant impact on the achievement of Sustainable Development Goals for universal basic education (UBE). Design/methodology/approach: This study draws from semi-structured interviews of 15 heads and proprietors -- six state-funded schools, six faith schools and three other privately owned schools -- to examine and compare the different motivations, guiding principles and overall impact of these actors in the education sector. Findings: Religious actors, along with private providers, are making a significant contribution to the provision of basic education in Nigeria. Students from faith schools tend to perform better academically and they also tend to be more disciplined and resourceful. However, because these schools are fee-paying, fewer households are able to access them. Practical implications: The findings highlight the need to facilitate better cooperation and knowledge transfer activities between public, private and faith schools. It also emphasises the need for better government commitment and investment in provision of resources and facilities, effort in regulating the curriculum and regular inspection and quality monitoring of public schools. Originality/value: The study highlights, on the one hand, the superior capacity of non-state actors -- especially religious actors -- to deploy their vast social capital towards the mobilisation of funds and human resources. On the other hand, while they have made inroads in their share of total national school enrolment, non-state actors have not made significant impact on access to quality education, owing to high fees and entry barriers faced by poorer households.