A relatively large number of South African learners drop out of school during the last 2 years of high school. This has important negative consequences for the individual learners, as well as for the country as a whole since it contributes greatly to the high number of unskilled and unemployed people. This study was carried out to explore whether, aside from gender and school environment, learners' motivation can serve as a predictor of the (un)successful transition of learners from grades 11 to 12 in South Africa. A total of 1,355 grade 11 learners from previously advantaged, transition, and previously disadvantaged school environments in the Free State's Motheo district participated in the study. Self-determination theory and general theories of learner motivation were used as the underlying theoretical basis for the selection of the predictors. Results showed that the number of unsuccessful learners was much higher among boys and in previously disadvantaged schools. We did not find the importance attached to intrinsic and extrinsic goals to predict the (un)successful transition. We did, however, find that successful transition is associated with higher levels of learner motivation, a more positive attitude towards learning and lower levels of educational anxiety. Finally, in comparison with their unsuccessful peers, learners who were successful in the transition to grade 12 were significantly more autonomously motivated and showed significantly less controlled motivation.