We investigated associations between family income-to-needs, nighttime bedroom temperature (NBT), and children's sleep. Using a sample of 46 children (M age = 11.5), we recorded NBT and objective sleep parameters via actigraphy nightly for one week to evaluate within- (night-to-night) and between-person associations. We found consistent evidence for a curvilinear association between NBT and sleep variables at the between-person level, indicating that children who slept in rooms that were "too hot" or "too cold" experienced poorer sleep. Moreover, children in lower income-to-needs families had more extreme NBTs. There was some evidence that family income-to-needs is indirectly related to sleep via NBT, but with interpretational caveats. These findings point to NBT as a potentially modifiable variable, which has implications for practical applications to mitigate effects of socioeconomic disparities on children's sleep.