Neighborhood measures of social vulnerability encompassing multiple sociodemographic factors can be used to quantify disparities in outcomes. We hypothesize patients with high Social Vulnerability Index (SVI) are at increased risk of morbidity following colectomy. We used local 2012–2017 National Surgical Quality Improvement Program (NSQIP) data to study colectomy patients, examining associations between SVI and postoperative outcomes. We included 976 patients from five hospitals. High SVI (>75th percentile) was associated with increased postoperative morbidity on unadjusted analysis (OR 1.84, 95% CI 1.35–2.52, p < 0.001); this association persisted after adjusting for demographics and comorbidities (OR 1.63, 95% CI 1.15–2.31, p = 0.005). The association with SVI was not significant after adjusting for perioperative risk modifiers such as emergent presentation (OR 1.37, 95% CI 0.95–1.98, p = 0.10). High social vulnerability is associated with increased postoperative complications. This effect appears mediated by perioperative risk factors, suggesting potential to improve outcomes by facilitating timely surgical intervention. •The Social Vulnerability Index (SVI) is associated with surgical outcomes.•Patients undergoing colectomy at five hospitals were examined.•Postoperative morbidity was higher for patients with high SVI.•This effect appears to be mediated by perioperative/intraoperative risk factors.•This suggests potential to improve outcomes by facilitating timely surgical intervention.