Objectives: Our main objective was to evaluate the percentage of patients under anti-osteoporotic treatment (OT) at the time of hip fracture (HF) and one and four years after the HF event. We compared these results with the percentage of patients who should be under treatment at all three stages, according to the recently published Portuguese cost-effectiveness recommendations (PCER) for OT. Data regarding occurrence of new fragility fractures and mortality were also determined, one and four years after the HF event. Our secondary objective was to evaluate characteristics of patients associated with OT at the time of hip fracture.. Material and Methods: Patients hospitalized due to HF between May 1st and October 31st of 2013 in a single tertiary hospital, were selected for this study. Data regarding demographic, clinical features (including the clinical risk factors for fracture considered by FRAX®), level of independence in daily activities (Katz index), comorbidity (Charlson index) and OT were recorded at the time of the HF. The subsequent risk of fracture was estimated for each patient with FRAX® (without mineral bone density). Mortality and the percentage of patients receiving an OT prescription and suffering a new osteoporotic fracture, at one and four years after the HF event, were established. Results: One hundred and thirty patients were included, with a mean age of 81.6±8.6 years. At the time of the HF only 28(21.5%) of the patients were receiving some form of OT. According to PCER, 115(88.5%) of these patients should be undergoing treatment according to FRAX® estimated risk, 30(23.1%) based on previous fractures and 119(91.5%) based on either criteria. The score of comorbidities was negatively associated with the prescription of OT at baseline (OR=0.17 [0.05-0.53], p=0.011) while the level of independence in daily activities was associated with higher probability of being treated (OR=3.20 [1.30-7.89], p=0.003). At one year after the HF, 39/130(30%) of patients had died. Although, according to PCER, all the remaining patients should be under OT based on the history of HF, only 11/91(12.1%) had received an OT prescription and 5/91(5.5%) suffered a new osteoporotic fracture during this period. At four years after the HF, 65/130 (50%) of patients had died. Only 6 of the remaining 65 (9.2%) were receiving an OT prescription and 9/65(13.8%) had suffered an additional fractured. Conclusions: Similar to other countries, the percentage of patients receiving OT at the time and especially after a HF is extremely low. Risk estimations with FRAX® and application of current PCER should allow clinicians to introduce appropriate primary and secondary preventive measures. Comorbidities and dependence seem to be important reasons for this undertreatment.