Mathematics achievement is core to South Africa's readiness for digital innovation, yet current pass rates in this subject are below the global average. Simply attributing mathematics performance to intelligence does not fully account for the multifaceted reality of achievement in the subject. The current study investigated the value of both cognitive and behavioural factors in predicting mathematics performance, as well as explored the interactions between these factors. A quantitative, cross-sectional design was employed. Grade 9 learners (N = 187) completed the Ravens' Standard Progressive Matrices and the Study Orientation towards Mathematics assessments to establish their fluid intelligence, study attitude, mathematics anxiety, study habits, problem-solving behaviours and study milieu. Pearson correlation coefficients established the relationships between fluid intelligence, study orientations towards mathematics, and mathematics marks. These factors were also included in a linear regression and dominance analysis to compare their relative weights in influencing mathematics performance. Study attitude and fluid intelligence were found to be the most dominant, significant factors in the model, which explained 39% of the total variance (R[superscript 2] = 0.390, F(6, 180), = 19.2, p <0.001). Moderator regressions between fluid intelligence and each of the study orientations further found that fluid intelligence and study orientations, with the exception of study milieu, independently influence mathematics performance.