There are few data on indications for central venous catheter (CVC) use. We conducted an observational, hospital-wide prospective cohort study to quantify the indications for catheter placement over dwell time and to investigate agreement between healthcare workers (HCWs) on CVC use. Catheter use was observed by on-site visits, HCW interviews, and screening of patient charts. A total of 378 CVCs were inserted in 292 patients, accounting for 2704 catheter-days. Of these, 93% CVCs were multilumen catheters and 70% were placed in the intensive care unit (ICU). Median dwell time (interquartile range) was 5 (2-9) days overall, and 4 (2-7) and 8 (3-15) in the ICU and non-ICU settings, respectively. The mean number of specified indications for CVC use per day was 1.7 (1.9 for ICU and 1.5 for non-ICU; P<0.001). The most frequent reason (49%) for catheter use was prolonged (>7 days) antibiotic therapy followed by parenteral nutrition (22.3%). A total of 130 catheter-days (4.8%) were unnecessary with a higher proportion in non-ICU settings (6.6%). In 94% of cases, there was agreement among HCWs on indications for CVC use. However, 35 on-site visits (8.3%) in non-ICU settings revealed that neither the nurse nor the treating physician knew why the catheter was in place. ICU catheters have a short dwell time but are utilised more often, whereas catheters in non-ICU settings show a reverse characteristic. Prevention measures targeting catheter care are more likely to be successful in non-ICU settings.