Research has illuminated contributions--usually modeled separately--of both executive functioning (EF) and visuomotor integration (VMI) to mathematical development in early elementary school. This study examined simultaneous associations of EF and VMI, measured at the beginning of the school year, with concurrent and later mathematics performance on several mathematics assessments in kindergartners (n = 89, M[subscript age] = 5.5 years) and first graders (n= 73, M[subscript age] = 6.6 years) of low socioeconomic status. Both skills were related to concurrent performance on all assessments, as well as improvement through the end of the school year for all but a geometry subtest, which was predicted only by VMI. No significant influence of an interaction between the skills was present, except for concurrently on the geometry subtest and longitudinally on an assessment with a relatively strong emphasis on informal skills. Findings are discussed in the context of supporting mathematics development in early childhood.