Background: Patients with sickle cell disease (SCD) visit emergency departments (EDs) in rates leading to a significant health system burden. However, limited comprehensive evaluations of utilization patterns have been published using data connecting visits to patients across facilities. This study aims to examine sociodemographic predictors of ED utilization in SCD. Procedure: This retrospective cohort study employed 2007 data from the California Office of Statewide Health Planning and Development (OSHPD). Data included all ED encounters from California hospitals; identifiers connected each visit to an individual patient, across all facilities in the state. Multivariate regression techniques evaluated sociodemographic predictors of utilization while adjusting for confounding variables. Results: In 2007, 2,920 California patients with SCD made 16,364 ED visits. Adults ≥21 years of age had higher ED visit rates than children and were more likely to both be in the highest tier of users and visit multiple facilities. Patients living further from a self-identified provider of comprehensive SCD care had higher rates of ED visits and a lower likelihood of hospitalization from the ED. Publicly insured patients had higher rates of ED visits and were more likely to be in the highest tier of users than were the privately insured or uninsured. Conclusions: Adulthood ≥21 years of age, distance from comprehensive SCD care, and insurance status are significant predictors of ED utilization in SCD. As a routine source of care decreases ED utilization, these findings prompt concern that these factors act as barriers to accessing comprehensive SCD care. © 2011 Wiley Periodicals, Inc.