Summary: We used the Greek nationwide database to capture individuals on anti-osteoporotic treatment during 2019. From the estimated number of 683,679 osteoporotic individuals, only 42% were receiving treatment, with the total annual cost being almost one-tenth of the total cost of fractures. The treatment gap was significantly higher in males than in females. Introduction: Based on the 2019 European scorecard (SCOPE), osteoporosis is diagnosed in an estimated 683,679 individuals in Greece, with the direct cost of incident fractures being €694.7 million, although further relevant real-world data are scarce. Methods: The e-Government Center for Social Security Services prescription database, which covers almost 100% of the Greek population, was used to capture all individuals on anti-osteoporotic treatment during 2019. Results: A total of 288,983 among 8,641,341 people, corresponding to 3.3% of the total adult Greek population, had filled at least one anti-osteoporotic prescription (6.0% and 0.36% for females and males, respectively). Prevalence of anti-osteoporotic treatment increased with age, from 0.15% in those younger than 50 to 8.6% in those older than 70 years. Oral bisphosphonates were more frequently prescribed (58.8%), followed by denosumab (39.4%). Alendronate was more frequently prescribed in males and in people younger than 60 years. Denosumab was more frequently prescribed in females and in people older than 60 years. Selective estrogen-receptor modulators, teriparatide, and parenteral bisphosphonates accounted for 1.1%, 1.0%, and 0.02% of all prescriptions, respectively. Orthopedic surgeons (39.6%), endocrinologists (19.6%), general practitioners (19%), and rheumatologists (9.3%) prescribed the vast majority of anti-osteoporotic regimens, with significant differences in prescription patterns. The annual cost of treatment per patient increased significantly with age, being on average €323.33. Conclusions: Less than half of the estimated number of individuals with osteoporosis in 2019 in Greece received treatment, with the total annual cost being far less than the estimated cost of incident-fragility fractures. The impact of this undertreatment on related health care costs merits further investigation.