There is limited evidence on the costs associated with ipilimumab. We investigated healthcare costs of all Dutch patients with advanced cutaneous melanoma who were treated with ipilimumab. Data were retrieved from the nation-wide Dutch Melanoma Treatment Registry. Costs were determined by applying unit costs to individual patient resource use. A total of 807 patients who were diagnosed between July 2012 and July 2015 received ipilimumab in Dutch practice. The mean (median) episode duration was 6.27 (4.61) months (computed from the start of ipilimumab until the start of a next treatment, death, or the last date of follow-up). The average total healthcare costs amounted to €81 484, but varied widely (range: €18 131-€160 002). Ipilimumab was by far the most important cost driver (€73 739). Other costs were related to hospital admissions (€3323), hospital visits (€1791), diagnostics and imaging (€1505), radiotherapy (€828), and surgery (€297). Monthly costs for resource use other than ipilimumab were €1997 (SD: €2629). Treatment-naive patients (n=344) had higher total costs compared with previously-Treated patients (n=463; €85 081 vs. €78 811). Although patients with colitis (n=106) had higher costs for resource use other than ipilimumab (€11 426) compared with patients with other types of immune-related adverse events (n=90; €9850) and patients with no immune-related adverse event (n=611; €6796), they had lower total costs (€76 075 vs. €87 882 and €81 480, respectively). In conclusion, this nation-wide study provides valuable insights into the healthcare costs of advanced cutaneous melanoma patients who were treated with ipilimumab in clinical practice. Most of the costs were attributable to ipilimumab, but the costs and its distribution varied considerably across subgroups.