Osteoporotic-related fractures cause significant patient disability, leading to a growing burden on health care systems. Effective secondary fracture prevention can be delivered by fracture liaison services (FLSs), but these are not available in most countries. A major barrier is insufficient policy prioritization, helped by the lack of economic assessments using national data and providing estimates of patient outcomes alongside health care resource use and cost impacts. The aim of this study was to develop an economic model to estimate the benefits and budget impact of FLSs and support their wider international implementation. Five interconnected stages were undertaken:​ establishment of a generic patient pathway;​ model design;​ identification of model inputs;​ internal validation and output generation;​ and scenario analyses. A generic patient pathway including FLS activities was built to underpin the economic model. A state-based microsimulation model was developed to estimate the impact of FLSs compared with current practice for men and women aged 50 years or older with a fragility fracture. The model provides estimates for health outcomes (subsequent fractures avoided and quality-adjusted life years [QALYs]), resource use, and health and social care costs, including those necessary for FLSs to operate, over 5 years. The model was run for an exemplar country the size of the United Kingdom. FLSs were estimated to lead to a reduction of 13,149 subsequent fractures and a gain of 11,709 QALYs. Hospital-bed days would be reduced by 120,989 and surgeries by 6455, while 3556 person-years of institutional social care would be avoided. Expected costs per QALY gained placed FLSs as highly cost-effective at £8258 per QALY gained over the first 5 years. Ten different scenarios were modeled using different configurations of FLSs. Further work to develop country-specific models is underway to delivery crucial national level data to inform the prioritization of FLSs by policy makers.