Poor sleep can negatively impact children's academic performance. However, it is unknown whether early-life socioeconomic status (SES) moderates later sleep and academics. We tested associations between actigraphy-based sleep duration and midpoint time, and parent-reported sleep problems with objective and subjective measures of academic performance. We also examined whether relations varied by early and concurrent SES. Children (n=707; 52% female; M age =8.44 years; 28.7% Hispanic/Latinx; 29.7% at/below poverty line) were assessed at 12 months for SES and eight years for SES, sleep, and academics. There were no main effects of sleep on academics. More sleep problems predicted lower Applied Problems performance for low SES children ( b =-.73, p <.05) and better performance for high SES children ( b =.69, p <.05). For high SES children, greater sleep problems ( b =-.11, p <.05) and longer sleep duration ( b =-.11, p <.05) predicted lower academic achievement. However, most associations were consistent across SES, illustrating the complex interplay between sleep, academic outcomes, and SES.