BACKGROUND Rates of cigarette smoking among the public and individuals with mental illness have been well documented. Studies have demonstrated that prevalence of smoking among individuals with mental illness remains elevated compared to the general population and as a distinct subgroup, individuals with mental illness consume more than a third of cigarettes sold in the U.S. However, information on rates of smoking among patients presenting to a psychiatric emergency room (ER) is lacking. This study assesses this understudied population for smoking prevalence and associated factors. METHODS A retrospective chart review of 203 distinct psychiatric ER patients was conducted. Demographics, tobacco use, substance use, psychiatric diagnoses, and family history were noted and analyzed with SPSS. RESULTS Tobacco use rates were noted to be nearly fifty percent and significant associations were found with active suicidal ideation, alcohol use disorders, illicit drug use disorders, and history of prior psychiatric hospitalization. CONCLUSIONS Tobacco use among psychiatric ER patients is much higher than that of the general population and associated with active suicidal ideations, alcohol use disorders, and illicit substance use disorders. These findings should be considered in the evaluation and expectant management of these patients by their clinicians and healthcare providers.