Objective: Computed tomography (CT) use among patients who present to emergency departments (EDs) with rhinosinusitis symptoms is not well described. We aim to: 1) describe sinus CT utilization patterns, and 2) identify predictors of use. We hypothesize that patient symptoms, socioeconomic factors, and gender may influence the decision to obtain a sinus CT scan. Study Design: Retrospective review. Methods: The Nationwide Emergency Department Sample (2009-2011) was queried for patient encounters with a primary diagnosis of sinusitis (International Classification of Diseases, Ninth Revision, Clinical Modification codes 461*, 473*). Patient demographics, comorbidities, and disposition were obtained. Factors associated with CT scan use were determined by univariable and multivariable logistic regression. Results: A total of 2,297,830 visits were attributed to a primary diagnosis of sinusitis. The majority of patients were adult (age >17) (80.8%) and female (63.7%). Computed tomography imaging was obtained in 56,088 patients (2.4%). In univariable analysis, many socioeconomic factors were predictive of imaging, including private insurance (P < 0.0001), metropolitan patient residence (P < 0.0001), and higher median household income quartile (P < 0.0001). The strongest predictors of CT use in multivariable analysis were history of injury (odds ratio [OR] = 2.82, 95% confidence interval [CI] = 2.43-3.29), headache (OR 2.11, 95% CI 1.02-2.34), Northeast hospital location (vs. Midwest) (OR 1.91, 95% CI 1.46-2.49), and male gender (OR 1.40, 95% CI 1.34-1.47). Conclusions: Several socioeconomic, demographic, and geographic factors are associated with sinus CT scan use in the ED for rhinosinusitis. This study has implications for CT imaging guidelines in the ED setting and demonstrates a need for further investigation of healthcare utilization disparities.