This study aimed to describe the 12-month period prevalence and risk factors for suicidal ideation and behaviour in a cohort of patients with pathological gambling attending a treatment service. Seventy-nine people with a diagnosis of pathological gambling received a mail out survey that included questions on postulated risk factors for suicidal ideation and behaviour, the modified Suicide Ideation Scale (SIS), the South Oaks Gambling Screen (SOGS), the Beck Depression Inventory (BDI) and the CAGE. A total of 54.4% of the surveys were returned completed. There were 81.4% who showed some suicidal ideation and 30.2% reported one or more suicide attempts in the preceding 12 months. Suicidal ideation and behaviours were positively correlated with the gambling severity (SOGS scores), the presence of debt attributed to gambling, alcohol dependence and depression (BDI). Suicidal ideation/behaviour was not significantly associated with gender and living arrangements, nor a history of receiving treatment for depression during the preceding 12 months. People with pathological gambling attending a treatment service had higher levels of suicidal ideation and behaviour than previous studies. Pathological gambling should be seen as a chronic condition with a similar risk for suicidal ideation and behaviour as other mental illnesses. Counselling services, general practitioners and mental health services should screen for gambling problems when assessing risk after suicide attempts and for suicide risk in patients presenting with gambling problems and co-morbid depression, alcohol abuse and a previous suicide attempt.