Background Community treatment orders (CTOs) enable patients to be treated in the community rather than under detention in hospital. Population-based studies of suicide among patients subject to a CTO are scarce. Aims To compare suicide rates among patients subject to a CTO with all discharged psychiatric patients and those detained for treatment but not subject to a CTO at discharge (‘CTO-eligible’ patients). Method From a national case series of patients who died by suicide within 12 months of contact with mental health services in England during 2009–2018, we estimated average annual suicide rates for all discharged patients, those on a CTO at the time of suicide, those ever treated under a CTO and CTO-eligible patients. Results Suicide rates for patients on a CTO at the time of suicide (191.3 per 100 000 patients) were lower than all discharged patients (482.3 per 100 000 discharges). Suicide rates were similar in those ever treated under a CTO (350.1 per 100 000 CTOs issued) and in CTO-eligible patients (382.9 per 100 000 discharges). Suicide rates within 12 months of discharge were higher in persons ever under a CTO (205.1 per 100 000 CTOs issued) than CTO-eligible patients (161.5 per 100 000 discharges), but this difference was reversed for rates after 12 months of discharge (153.2 per 100 000 CTOs issued v. 223.4 per 100 000 discharges). Conclusions CTOs may be effective in reducing suicide risk. The relative benefits of CTOs and intensive aftercare may be time-dependent, with the benefit of a CTO being less before 12 months after discharge but greater thereafter. CTO utilisation requires a careful balancing of patient safety versus autonomy.