OBJECTIVES: To calculate national estimates of Necrotizing Enterocolitis (NEC)–related hospitalization and associated use of health care resources to explore the effects of certain patient and hospital characteristics on use of hospital resources and length of stay in the United States. METHODS: Data from the 2009 Healthcare Cost and Utilization Project Kids’ Inpatient Database was used. Pediatric inpatient care in 4121 hospitals in 44 US states. Inpatient admissions with an International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis of Necrotizing Enterocolitis. National estimates of NEC-associated hospitalizations were calculated. Potentially significant covariate associations were studied using hospital costs and Lengths of Stay as dependent variables. Predictors of high hospitalization cost and prolonged length of stay were evaluated using multivariable logistic regression. RESULTS: