Background: Three quarters of UK suicides were not in contact with mental health services one year before dying. The characteristics of this group of suicides have not been adequately explored. Aim: Identify risk factors in no-contact suicides and explain non-referral to Mental Health Services (MHS). Method: Ongoing, observational, retrospective survey of all suicides in West Kent (population 988,027) over 5 years. No contact suicides are compared with MHS suicides through standard questionnaires completed by consultant psychiatrists, and general practitioners, and by examining coroners' records. Results: No contact suicides were significantly more likely to be male, employed, living with others and not diagnosed with a mental disorder. They have a significantly lesser frequency of previous selfharm. Their suicide risk is retrospectively estimated to be lower. 50.5% of all suicides were either not registered, had no general practitioner contact, or were last seen 13 weeks or more before suicide. These characteristics can explain non referral to specialist services. Conclusion: No-contact suicides take place to a considerable extent outside the current limitations of primary health and social care systems. Many have a different risk factor profile, and are similar to people who do not seek medical help in the first place. Declaration of interest: None.