•Effects of dual-language input on bilingual children’s EF skills were examined.•Children’s shifting, inhibition, and monitoring skills were tested.•Language ability was found to moderate the effects of dual language exposure on EF.•Dual-language input was associated with better EF for children with better language.•Language ability thresholds graded effects of dual-language input on EF. The current study examined the effects of dual language exposure on executive function in 5- to 11-year-old Spanish–English bilingual children with different language skills. Dual language exposure was measured via parent report and was operationalized as the proportion of time spent in an environment where both English and Spanish were present. Executive function was measured via the Dimensional Change Card Sort (DCCS) task. Shifting costs, switching costs, and mixing costs were derived to index executive function performance. A significant interaction between extent of dual language exposure and language skills was observed such that children showed smaller shifting and mixing costs with increased dual language input as their language skills increased. The results suggest a graded effect of dual language exposure on executive function, where a robust language system may be required for dual language exposure to influence executive function.