To examine the demographic and workplace risk factors of serious falls and associated economic burden in Canadian health care workers. Fall injury data during 2005-2008 from a workplace health and safety surveillance system were linked with workers' compensation claims and payroll records. The costs for treatment and wage loss and days lost for accepted time-loss claims were calculated. Demographic and work-related factors were identified to distinguish the risk for more serious falls from less serious falls. Nine hundred and thirty-eight fall injury claims were captured among 48 519 full-time equivalent workers. Workers >60 years, part time or employed in the long-term care sector sustained a higher proportion of serious falls (>70%). Over 75% of falls were serious for care aides, facility support service workers and community health workers. In the multivariate analysis, the risk of serious falls remained higher for workers in the long-term care sector [odds ratio (OR) 1.71; P < 0.05] compared with those in acute care and for care aides (OR 1.72; P < 0.05), facility support service workers (OR 2.58; P < 0.01) and community health workers (OR 3.61; P < 0.001) compared with registered nurses (RNs). The median number of days lost was higher for females, long-term care workers, licensed practical nurses and care aides. Females, long-term care workers, RNs, licensed practical nurses, care aides and maintenance workers had the most costly falls. Reducing work-related serious fall injuries would be expected to bring about significant benefits in terms of reduced pain and suffering, improved workplace productivity, reduced absenteeism and reduced compensation costs.