OBJECTIVES: Although osteoporosis treatment can dramatically reduce fracture risk, rates of treatment after hip fracture remain low. In-hospital initiation of recommended medications has improved outcomes in heart disease; hospitalization for hip fracture may represent a similar opportunity for improvement. The objective of this study was to examine rates of in-hospital treatment with a combination of calcium and vitamin D (Cal+D) and antiresorptive or bone-forming medications in patients hospitalized for hip fractures DESIGN: Observational cohort. SETTING: Three hundred eighteen hospitals in the United States. PARTICIPANTS: Fifty-one thousand three hundred forty-six patients aged 65 and older hospitalized for osteoporotic hip fracture. MEASUREMENTS: In-hospital administration of Cal+D and antiresorptive or bone-forming medications. RESULTS: Three thousand four hundred five patients (6.6%) received Cal+D anytime after a procedure to correct femoral fracture; 3,763 patients (7.3%) received antiresorptive or bone-forming medications. Only 1,023 patients (2.0%) were prescribed ideal therapy, receiving Cal+D and an antiresorptive or bone-forming medication. Treatment rates remained low across virtually all patient-, provider-, and hospital-level characteristics. The strongest predictor of treatment with Cal+D was the receipt of an antiresorptive or bone-forming medication (adjusted odds ratio=5.50, 95% confidence interval=4.84-6.25), but only 27.2% of patients who received these medications also received Cal+D. CONCLUSION: Rates of in-hospital initiation of osteoporosis treatment for patients with hip fracture are low and may represent an opportunity to improve care.