Significant disparities exist between patients of different races and with different family incomes; less is understood regarding community-level factors on outcomes. In this study, we used linked data from the Pediatric Health Information System database and the US Census Bureau to examine associations between median annual household income by zip code and mortality, length of stay, inpatient standardized costs, and costs per day, over and above the effects of race and payer, first for children undergoing cardiac surgery (2005-2015) and then for all pediatric discharges (2012-2015). Median community-level income was examined as continuous and categorical (by quartile) predictors. Hierarchical logistic and censored linear regression models were constructed. To these models, patient and surgical characteristics, year, race, payer, state, urban or rural designation, and center fixed effects were added. We identified 101 013 cardiac surgical (and 857 833 total) hospitalizations from 46 institutions. Children from the lowest-income neighborhoods who were undergoing cardiac surgery had 1.18 times the odds of mortality (95% confidence interval CI: 1.03 to 1.35), 7% longer lengths of stay (CI: 1% to 14%), and 7% higher standardized costs (CI: 1% to 14%) than children from the highest-income neighborhoods. Results for all children were similar, both with and without any major chronic conditions. The effects of neighborhood were only partially explained by differences in race, payer, or the centers at which patients received care. There were no differences in costs per day. Children from lower-income neighborhoods are at increased risk of mortality and use more resource intensive care than children from higher-income communities, even after accounting for disparities between races, payers, and centers.