This study aimed to assess the cost‐utility of a Fracture Liaison Service (FLS) with a systematic follow‐up according to patients' follow‐up compliance trajectories. The Lucky Bone™ FLS is a prospective cohort study conducted on women and men (≥40 years) with fragility fractures. Dedicated personnel of the program identified fractures, investigated, treated, and followed patients systematically over 2 years. Groups of follow‐up compliance trajectories were identified, and Markov decision models were used to assess the cost‐utility of each follow‐up trajectory group compared to usual care. A lifetime horizon from the perspective of the healthcare payer was modeled. Costs were converted to 2018 Canadian dollars and incremental cost‐utility ratios (ICURs) were measured. Costs and benefits were discounted at 1.5%. A total of 532 participants were followed in the FLS (86% women, mean age of 63 years). Three trajectories were predicted and interpreted;​ the high followers (HFs, 48.4%), intermediate followers (IFs, 28.1%), and low followers (LFs, 23.5%). The costs of the interventions per patient varied between $300 and $446 for 2 years, according to the follow‐up trajectory. The FLS had higher investigation, treatment, and persistence rates compared to usual care. Compared to usual care, the ICURs for the HF, IF, and LF trajectory groups were $4250, $21,900, and $72,800 per quality‐adjusted life year (QALY) gained, respectively ($9000 per QALY gained for the overall FLS). Sensitivity analyses showed that the HF and IF trajectory groups, as well as the entire FLS, were cost‐effective in >67% of simulations with respect to usual care. In summary, these results suggest that a high‐intensity FLS with a systematic 2‐year follow‐up can be cost‐effective, especially when patients attend follow‐up visits. They also highlight the importance of understanding the behaviors and factors that surround follow‐up compliance over time as secondary prevention means that they are at high risk of re‐fracture.