Purpose This study aimed to identify risk factors that predicted staff judgements about previous or current suicide risk in offenders under probation supervision in a metropolitan probation trust. Method The study used data from Offender Assessment System risk assessment electronic records. Data were collected on staff judgements about previous or current risk of suicide in 38,910 offenders under community supervision in 2009/2010. Data on demographic, offence related, clinical, historical, and situational factors known to be linked with risk of suicide in relevant populations were also gathered. Results Twelve per cent of the sample were identified as previously or currently ‘at risk’ of suicide. A logistic regression revealed seven factors that reliably predicted staff decisions about suicide risk. The most significant factor which had a large effect on staff judgements was previous history of self‐harm, suicide attempts or suicidal thinking. Other factors which had a small effect on judgements included coping skills, psychiatric treatment/medication, attitude to self, childhood abuse, current psychological problems/depression, and history of close relationship problems. Several prominent risk factors for suicide in related populations did not strongly predict risk decisions including alcohol misuse, offence type, social support, age, and gender. Conclusions The study highlighted that working with offenders ‘at risk’ of suicide is a regular element of probation practice. The findings suggest that transferable risk assessment skills may support staff in suicide risk decisions. However, they also underline the need to raise awareness of prominent suicide risk factors to support staff in this challenging area of practice. The study findings strengthen support for the provision of suicide awareness training for all staff. Further research should explore staff decisions in more depth and seek to develop our understanding of risk factors associated with actual suicidal behaviour in community offenders.