Central to the pursuit of education and its functions like assessment, is social justice. Given the (still) existing inequalities brought about by years of neglect, it is clear that the building of a just society is indeed fraught with challenges. This article explores the extent to which all learners in South Africa are afforded fair treatment and an impartial share of what the education system through assessment practices can offer them. In attempting to illuminate this issue, we will start by providing a brief overview of assessment policy initiatives and the current assessment system in South Africa. This will be followed by a conceptual analysis of assessment practices and their social justice implications for learners by using Cribb and Gerwitz's (2003) key dimensions of social justice, namely the distribution of educational resources, recognition and respect for cultural differences and participation. Through this analysis we conclude that, while acknowledging the massive impact of family/community circumstances and poor educational provision, unfair assessment practices as discussed remain an important dimension of the degradation of social justice in the South African education system. Many learners, despite efforts to ensure more just assessment practices, are still marginalised and do not reap the benefits that can support them in developing their full potential.