Background: Little is known about the psychological health or treatment experiences of those who have left the British armed forces.

Aims: To describe the frequency and associations of common mental disorders and help-seeking behaviours in a representative sample of UK veterans at high risk of mental health problems.

Method: A cross-sectional telephone survey of 496 'vulnerable' ex-service personnel selected from an existing epidemiological military cohort.

Results: The response rate was 64%; 44% of these had a psychiatric diagnosis, most commonly depression. Those with a diagnosis were more likely to be of lower rank and divorced or separated. Just over half of those with self-reported mental health problems were currently seeking help, most from their general practitioners. Most help-seekers received treatment, usually medication; 28% were in touch with a service charity and 4% were receiving cognitive-behavioural therapy.

Conclusions: Depression is more common than post-traumatic stress disorder in UK ex-service personnel. Only about half of those who have a diagnosis are seeking help currently, and few see specialists.