OBJECTIVE This paper describes the extent of heavy use of inpatient psychiatric services. It reveals predictors of heavy use. METHODS 969 users of inpatient psychiatric services in the city of Leipzig were identified based on health insurance data. RESULTS 16,7 % of the patients had at least 3 admissions and were classified as heavy users. They accounted for 36,4 % of the total inpatient cost. Patients suffering from schizophrenia or a comorbidity with personality disorders had a higher risk to be a heavy user. The kind of facility and the way of discharge were also predictors for heavy use. CONCLUSIONS Further qualitative analyses should identify reasons for heavy users to utilize inpatient services and find out other opportunities of care for these patients.