Abstract Study question What are the potential costs to the Irish healthcare system of implementing a ‘best practice’ model of care for recurrent miscarriage clinics? Summary answer Total cost for RM patients ranges from €1,634.19 to €4,817.87 for a pregnancy outcome and from €1,245.77 to €4,317.87 for women who do not conceive. What is known already Recurrent miscarriage (RM) affects 1% -5% of the reproductive age population. It is recognised that the best care for RM is offered in a dedicated recurrent miscarriage clinic (RMC). While RM represents a significant burden to couples, the setup of RMCs involves substantial resource costs. This study reports on the cost impact to the Irish healthcare system of implementing a ‘best practice’ model of care for RMCs. Evidence from cost analysis plays an important role in informing the cost-effectiveness of interventions ensuring that those available resources are used efficiently, as health policymakers plan for future healthcare services. Study design, size, duration A micro-costing approach was employed using a range of data sources to identify, measure, and value the resources required to implement the proposed model of care. Data was collected from March – September 2021. The cost analysis was calculated using the following components: 1. The initial set up costs of a best practice RMC, 2. The ongoing implementation costs of delivering a best practice RMC, and 3. The subsequent and related care pathway costs. Participants/materials, setting, methods Per patient costs were estimated within a best practice RMC using two scenarios (a typical versus a complex RM case). The cost estimates were extrapolated to estimate the cost impact to the Irish healthcare care system over a 1-year period using population data and published prevalence rates for RM. A sensitivity analysis was performed to control for the uncertainty in each of the parameters. Main results and the role of chance The total cost to set up a best practice RMC is €37,321. The yearly on-going delivery cost is €6,212.25. The total cost for a RM patient who has another pregnancy after receiving investigations, treatment and reassurance scans ranges between €1,634.19 (typical) and €4,817.87 (complex). For a RM patient who does not conceive again, costs range from €1,245.77 (typical) to €4,317.87 (complex). Using population estimates, the total budget impact to the health service for women who experience ≥2 losses costs €61,927,630 (typical) /€20,336,229 (complex) for a pregnancy outcome and €22,480,630 (typical)/€7,78,437 (complex) for women who do not conceive. Sensitivity analysis identified RM investigations and treatments costs as the main cost drivers for per-patient costs. Limitations, reasons for caution With only six RMCs operating in Ireland, calculating costs savings was not possible. A fixed number of investigations and treatments for patient scenarios were applied. In a real-world setting, investigations and treatments will vary significantly by patient need, risk factors and previous history of loss, directly impacting the costs reported. Wider implications of the findings This study proposes a model of care for RMCs in Ireland, providing cost estimates at the patient and healthcare system level. While future studies should consider the cost-effectiveness of this model of care, this analysis provides a valuable first step in providing a breakdown of the resources and costs. Trial registration number Not applicable