Aims Heart failure (HF) represents an increasing burden on health-care systems because of the aging population. The aim of this study was to explore its costs of care in Germany from the payer perspective and to identify the main drivers. Subjects and methods As part of a trial, primary care physicians (PCPs) enrolled eligible patients and documented actual clinical and 12-month retrospective ambulatory healthcare utilisation data related to HF [PCP and cardiologist contacts, and cardiovascular (CV) medication] and provided the doctors' reports of hospitalisations during 2004 and 2005, enabling the collection and calculation of costs. Furthermore, each hospitalisation was classified according to the cause of admission into HF, CVor other hospitalisation. Results Thirty-seven physicians enrolled 168 patients with complete data of 159 patients (95 %). Patients (mean age 68±10 years, 73 % male, 47 % ischaemic aetiology) had ascertained systolic HF (mean ejection fraction 33±7 %) with NYHA class II/III in 53/45 %. Mean (SD; median) annual costs of 96 hospitalisations, CV medication, and 337 cardiologist and 3,037 PCP practice contacts were 3,545 (8,065; 0), 854 (835; 638), 117 (105; 106) and 269 (190; 233) euros, respectively, totalling 4,792 (8249;1341) euros. Fourteen per cent of all patients incurred 50 % of total costs. Twenty-five HF, 49 CV and 22 other hospitalisations incurred 13, 73 and 14 % of hospital care costs, respectively. Conclusions These secondary outcome data might indicate a trend that neither HF ambulatory care nor hospitalisation but rather interventional cardiology is the main cost driver. Planning interventions aimed at reduced hospitalisation and costs should include further clarification of the mechanisms of CV hospitalisation and reimbursement. © Springer-Verlag 2012.