To describe the epidemiology of reported concussion derived from a large, nationally representative health survey, the microdata files of the Canadian National Population Health Survey (1996-1997) were analyzed. Respondents reported whether they had "any injuries that were serious enough to limit their normal activities" in the preceding 12 months and the nature of the most serious injury. A total of 99.8% of 81,804 eligible respondents, representing 28,606,100 Canadians, reported their injury experience within the preceding year, with 89 reporting a concussion. The annual prevalence of Canadians reporting a concussion as their most serious injury was 110 per 100,000 population (95% confidence interval: 80, 140). Those reporting concussion were more likely to be younger (P < 0.001) and male (P = 0.02). Males were significantly overrepresented in the 16-34 year-old group (P = 0.004). More than 54% of all concussions were sport-related (95% confidence interval: 39%, 67%), occurring at a place for recreation or sport, with sport having a role in >85% of concussions in the 16-34 year-old group. This study presents annual prevalence estimates of reported concussion, derived from a sizeable, nationally representative population survey.