ObjectiveHead and neck cancers (HNCs) have increased in prevalence and often require free‐flap reconstruction (FFR) after tumor ablation. Postoperative complications following FFR can be high, occurring in as many as 48% and 71% of cases. HNC patients also have many disparities in Social Determinants of Health (SDOH), but the potential impact of SDOH disparities on postoperative complications following FFR has not been formally assessed.Study DesignRetrospective cohort review.SettingAcademic Tertiary Care Institution in Northeast United States.MethodsPatients that underwent head and neck FFR between January 2018 and December 2021 were analyzed to determine associations between quartiles of the national Area Deprivation Index (ADI), a proxy for SDOH disparity, and various medical and surgical postoperative complications. Associations were assessed using χ2 analysis.ResultsTwo hundred four patients were included in the study, and 61 patients had 97 complications. Significant associations between higher national ADI quartile and incidence of several postoperative complications were identified, including any surgical complication (P = .0419), wound dehiscence (P = .0494), myocardial infarction (MI) (P = .0215), and sepsis (P = .0464).ConclusionThere are significant associations between SDOH disparities and postoperative surgical complications, wound dehiscence, MI, and sepsis following head and neck FFR. Addressing SDOH disparities in HNC is pivotal to enhance postoperative outcomes and promote holistic patient care.