Executive functions (EF) and task persistence are key factors in academic development. However, EF and persistence have rarely been examined together, and it remains unclear whether these two constructs are independently related to intellectual development. The present study addressed this gap by examining whether EF and persistence in kindergarten predict math and reading achievement in second grade. We assessed 88 children (51% female; mean age = 73.4 months) on EF and persistence tasks at T1 and obtained teacher ratings of their academic competence at T2 (mean age = 94.6 months). Regression analyses showed that both EF and persistence predicted math achievement, but only EF predicted reading achievement. To sum up, our findings suggest that persistence may be particularly relevant for math, reflecting the ability to endure and sustain. These are skills that are typically not captured by EF measures. Consequently, early interventions should target EF and persistence to support children's mathematical potential.