BACKGROUND: The cost of medical care associated with hip fracture has been reported but the cost of social care is less well understood. Social care costs include formal residential and home care and home adaptations, but also informal care from family and friends. This study investigated the utilisation and cost of care beyond acute hospital stays following hip fracture. METHODS: A multi-centre, prospective observational study of patients ≥60 years with a hip fracture in the United Kingdom (UK), with 120-day follow-up. Marginal costs were calculated, with scenario analysis projecting the cost to the UK hip fracture population. A two-part model was used to calculate the incremental mean cost attributable to complications following surgery. RESULTS: Amongst 16 679 patients with a hip fracture, the mean cost of social care was £15 525 (95% CI: 14 991-16 059) per person. Mean cost per person for the change in residential requirements was £1656 (95% CI: 1568-1743); formal and informal home care £12 849 (95% CI: 12 448-13 250); and home adaptations £1021 (95% CI: 976-1067). The projected national cost of social care in the first 120 days following all hip fractures in the UK was £1.25 billion. Incremental mean cost of social care for patients who developed a surgery-specific or general complication were £1264 (95% CI: 58-2469) and £1418 (95% CI: 792-2043) per person, respectively. CONCLUSION: Social care represents a substantial and often under-recognised component of the economic burden following hip fracture. Formal and informal care were major cost drivers after discharge from hospital and may rival or exceed the cost of acute hospital care.