Background: Although many with intellectual disability come to the attention of services for fire setting, research in this area is scarce, which poses challenges for management. Method: In this paper we examined those with a fire-setting history (n = 30), identified from a sample of 138 patients treated in a UK forensic intellectual disability service. Those with a fire-setting history were compared to those without this history on various clinical, forensic, and treatment outcome variables. Results: Fire-setting was associated with significant psychopathology, including psychosis and personality disorders. Only half of the fire setters had a formal arson conviction. Fire setters were more likely to have a violence conviction and criminal sections/restriction orders. Conclusions: Half of those with fire-setting histories did not have formal arson convictions, highlighting the need for thorough history taking. Prevalent comorbidity suggests interventions should focus on treating psychopathology before commencing offence-specific arson therapies.