OBJECTIVES: Recent in-hospital mortality data among heart failure (HF) patients in the Netherlands are lacking. This study described in-hospital mortality rates among HF patients in the Netherlands from 2005 to 2009. METHODS: The PHARMO database network includes, among other things, hospitalization records of approximately 3.2 million residents in the Netherlands. From this database, all patients with a hospitalization for HF between 2005 and 2008 were selected. The date of the first HF admission was defined as the index date. Patients hospitalized for HF in the 12 months prior to index date were excluded. Patients were followed from index date until end of data collection, death, or a maximum of 12 months, whichever occurred first. Crude mortality rates over time were determined during index HF admission, any HF readmission, and during any all-cause readmission .  RESULTS: The study included 9786 patients with an index HF admission. Mean (± SD) age was 77 (± 11) years and 52% were female. During index HF admission (mean (±SD) length of stay (LOS):11 (±10) days) 10% of patients died. Hence, 8,850 patients were at risk for readmission. During follow-up, 1,563 (18%) patients were readmitted for HF and 4,542 (51%) patients had an all-cause readmission. In-hospital mortality during HF readmission (mean (±SD) LOS: 11 (±9) days) was also 10%. In-hospital mortality during all-cause readmission (mean (±SD) LOS: 7 (±11) days), was 5%. Mortality rates over time from 2005 to 2009 were stable. Mean (±SD) number of days between hospital (re)admission and death was 10 (±13) days for the index HF admission and 12 (±12) days for both HF readmission and all-cause readmission (12 (±15) days). CONCLUSIONS: In most recent years, in-hospital mortality remains unchanged with 10% of HF patients dying during HF admission.