ObjectiveThis study aims to describe the pattern and trends in acute rheumatic fever (ARF)/rheumatic heart disease (RHD)-related hospitalisations and costs for Australians aged <65 years.MethodsThis retrospective linked data study measured trends in hospitalisations and costs for ARF, RHD and complications of ARF/RHD in Northern Territory, South Australia, Western Australia, Queensland and New South Wales between 1 July 2012 and 30 June 2017. Persons with ARF/RHD were identified from RHD registers and/or hospital records.ResultsOver the 5-year study period, 791 children, aged <16years (86.3% Indigenous), and 2761 adults, aged 16-64years (44.8% Indigenous), were hospitalised for ARF, RHD or associated complications. On average there were 296 paediatric admissions per year, increasing 6.1% annually (95% CI: 2.4-9.6%, P=0.001) and 1442 adult admissions per year, increasing 1.7% annually (95% CI: 0.1-3.4%, P=0.03). Total 5-year costs were AU$130.6m (AU$17.6m paediatric, AU$113.0m adult). Paediatric costs were mostly for ARF-related admissions whereas adult costs mostly involved valvular surgery. Emergency admissions and air ambulance transfers were common, particularly for non-metropolitan residents.ConclusionsSuccessful ARF/RHD prevention would deliver significant hospital cost savings. Investment in primary and specialist health care in regional areas may reduce emergency admissions and regional transfers, further reducing hospital burden.