The paper focuses on analysing grade 12 learner errors and the misconceptions in calculus at a secondary school in Limpopo Province, South Africa. As part of the analysis the paper outlines the nature of mathematics errors and misconceptions. Coding of learners' errors was done through the lens of a typological framework. The analysis showed that most of the errors and misconceptions were due to knowledge gaps in basic algebra. Also noted was that errors and misconceptions in calculus were related to learners' over-dependence on procedural knowledge which had no conceptual basis. On the other hand, learners sometimes had sound conceptual knowledge for which they had not acquired allied procedural knowledge needed to perform in particular questions. Implications of the study to the wider mathematics education community are highlighted.