Abstract Background Despite the increased attention for assessing the effectiveness of implementation strategies, most implementation studies provide little or no information on its associated costs. The focus of the current study was to provide a detailed report of the resource use and costs associated with implementation of a short stay programme for breast cancer surgery in four Dutch hospitals. Methods The analysis was performed alongside a multi-centre implementation study. The process of identification, measurement and valuation of the implementation activities was based on recommendations for the design, analysis and reporting of health technology assessments. A scoring form was developed to prospectively determine the implementation activities at professional and implementation expert level. A time horizon of 5 years was used to calculate the implementation costs per patient. Results Identified activities were consisted of development and execution of the implementation strategy during the implementation project. Total implementation costs over the four hospitals were €83.293. Mean implementation costs, calculated for 660 patients treated over a period of 5 years, were €25 per patient. Subgroup analyses showed that the implementation costs ranged from €3.942 to €32.000 on hospital level. From a local hospital perspective, overall implementation costs were €21 per patient, after exclusion of the costs made by the expert centre. Conclusions We provided a detailed case description of how implementation costs can be determined. Notable differences in implementation costs between hospitals were observed. Trial registration ISRCTN: ISRCTN77253391