The objective of the present study was to predict the economic consequences of healthcare-acquired infections arising among admissions to Australian acute care hospitals. A quantitative algorithm informed by epidemiological and economic data was developed. All acute care hospitals in Australia were included in the study and the participants included all admissions to general medical and general surgical specialties. The main outcome measures were the numbers of cases of healthcare-acquired infection and bed days lost annually. It was estimated that there are 175153 (95% credible interval 155911:195168) cases of healthcare-acquired infection among admissions to Australian hospitals annually, and the extra stay in hospital to treat symptoms accounts for 854289 bed days (95% credible interval 645091:1096244). If rates were reduced by 1%, then 150158 bed days would be released for alternative uses. This would allow ∼38500 new admissions. Healthcare-acquired infections in patients cause bed blocks in Australian hospitals. The cost-effectiveness of hospital services might be improved by allocating more resources to infection control, releasing beds and allowing new admissions. There exists an opportunity to improve the efficiency of the Australian health care system.