OBJECTIVES: The optimal treatment choice for the about 64,000 men diagnosed with prostate cancer each year in Germany still remains unclear. The objectives therefore were to estimate and compare costs under day-to-day conditions of caring for men in Germany with newly diagnosed LCLRPC using hormonal therapy (HT), active surveillance (AS), radiotherapy (RT), operation (OP), or watchful waiting (WW) – HAROW. METHODS: The long-term observational multi-centre HAROW study combined data collection from urologists (clinical data; utilized outpatient medical services, OMS) and from patients (employment status, QoL by EQ-5D, numerous health resource use items). Resource use was valued by year 2010 official prices in €. Direct costs (DC) were given by hospital treatment, OMS and drugs, inpatient rehabilitation, patients’ co-payments. Indirect costs (IC: sick leave, premature retirement, premature mortality) were estimated by 2010 gross domestic product/capita/day. Costs and quality-adjusted life-years (QALYs) were discounted by 3% per annum. Strategies without significant differences in QALYs/patient-year (PY) were compared by cost-minimization analysis (CMA) using mean costs/PY, remaining strategies by cost-utility analysis. RESULTS: From 07/2008 to 03/2013, 3063 LCLRPC patients (T1a–T2c, N0, M0; 67.3±7.5 years) were included from 257 urologists: AS n=452, RT n=378, HT n=210, HT+RT n=80, combination therapy (CT) n=137, OP n=1647, other therapy (OT) n=18, WW n=141. Observation period: average 1.9 years, maximum 4.6 years. From the societal perspective (DC+IC), HT+RT had the lowest cost/PY (€1033), followed by AS (€1265), RT (€1313), WW (€1316), HT (€1522), CT (€3209), OT (€5705), and OP had highest cost/PY (€6656). From the perspective of DC, WW showed he lowest cost/PY (€894), followed by RT (€905), HT+RT (€987), AS (€1014), HT (€1169), OT (€2176), CT (€2204), and OP had highest cost/PY (€5374). CONCLUSIONS: The HAROW study provides meaningful results on costs of different LCLRPC treatment strategies under day-to-day conditions of care in Germany to support decision making.