AbstractAimClinical trials and the need for new treatments were recently listed among the most important factors for child health. The aim of the present study was to describe some of our experiences with budget preparations in paediatric clinical trials.MethodsWe selected 10 trials sponsored by the pharmaceutical industry at the Pediatric Clinical Research Center at Sahlgrenska University Hospital in Gothenburg, Sweden. We compared the sponsor's initial budget (budget proposal from the sponsor), with the final budget (negotiated and agreed between sponsor and site) and identified areas where discrepancies may arise.ResultsThe mean difference in total budget amount between the initial budget and the final budget was +60% (mean 59%, range 31%–139%). The costs for preparation of the clinical trial, time spent for study activities and costs for examinations were identified as key budget items for these differences.ConclusionOur findings indicate that a substantial part of the trial‐related costs would not be covered by the sponsor, had the initial budget been accepted. A thorough review and budget negotiation, as well as to have a dedicated team member for this task, are essential to ensure equitable responsibility for the study‐related costs and to avoid discontinuation of trials.