International research suggests that early mathematical competences predicts later mathematical outcomes. In this paper, we build on our previous study of young children's mathematical competencies (MacDonald & Carmichael, 2015) to explore the relationship between mathematical competencies at 4-5 years, as measured by teacher ratings, and later results on Years 3, 5, 7 and 9 NAPLAN numeracy tests. Data from a nationally-representative sample of 2343 children participating in the Longitudinal Study of Australian Children (LSAC) are examined. In line with overseas studies, we report moderate correlations between pre-entry mathematics and later NAPLAN results. However, analysis of individual growth trajectories suggests that in fact early mathematics predicts the initial (Year 3) level, but not subsequent growth. This suggests that early mathematical competences are important for enhancing outcomes in early schooling, but that the quality of mathematics education provided in the schooling years is critical for future development.