INTRODUCTION: Socioeconomic disadvantage has been associated with increased complicated appendicitis rates. Our purpose was to analyze the complex interactions between social determinants of health (SDOH) and postoperative outcomes in pediatric appendicitis. MATERIALS AND METHODS: Children who underwent appendectomy at our institution (1/2015-12/2020) were retrospectively reviewed. We used home addresses to determine composite measures of neighborhood/area-level socioeconomic advantage (Area Deprivation Index [ADI] and Social Deprivation Index [SDI]), and other area-level indicators. We created a novel, composite outcome score computed as a weighted average of eight outcome measures. Feature selection and exploratory factor analysis were used to create a multivariate model predictive of outcomes. RESULTS: Of 1117 children with appendicitis, 20.59% had complicated (perforated) appendicitis. Factor analysis identified two multivariate latent factors; Factor 1 contained SDI, ADI, and % unemployed in the population, and Factor 2 contained % Hispanic and % foreign-born in the population. Low Factor 2 scores (communities with more Hispanic/foreign-born residents) were associated with increased length of stay, more frequent postoperative percutaneous drainage, and increased postoperative imaging. CONCLUSIONS: Interactions between SDOH and pediatric surgical care go beyond the individual patient and suggest that vulnerable populations are exposed to contextual conditions that may impact outcomes. Specifically, neighborhood-level factors, including the prevalence of Hispanic ethnicity and foreign-born individuals, are associated with outcomes in pediatric patients with complicated appendicitis. Reducing disparities in complicated appendicitis outcomes may involve addressing neighborhood-level SDOH through strategic reallocation of healthcare resources and developing targeted interventions to improve access to pediatric surgical care in underserved communities.