OBJECTIVES: Little is known about the health status and costs of individuals with osteo-arthritis (OA) in Ontario. The study objectives were to estimate the burden of OA in Ontario using health survey and administrative data. METHODS: The records of all Ontarians who participated in the Canadian Community Health Survey (CCHS), cycle 1.1 (2000/2001) and provided consent to data linkage were linked to the Ontario Health Insurance Program (OHIP) physician claims database and the Discharge Abstract Database (DAD) In-Patient (i.e. hospitalization) and Day-Procedure databases. OA individuals (N= 4,331) were identified using CCHS 1.1. A control group matched by age and gender was created (N=1,477). Socio-demographic variables, medical characteristics, health-related quality of life (HRQoL) and one-year physician, day procedures and hospitalization costs were determined. CCHS sample weights were applied to the data to represent the Ontario population. Logistic regressions, Tobit and Generalized Linear Model models were used to identify predictors of medical characteristics, utility and cost data, respectively. Bootstrap techniques were applied for the cost analyses.   RESULTS: The mean age of the population was 66 years old and 74% were female.  Compared to the control group, OA individuals were statistically more likely to: be female, be less physically active, be overweight or obese, reside in an urban community, have more comorbidities, have a lower HRQoL and a lower household income. The 1-year physician, day procedure and hospitalization costs were statistically higher in the OA group.   CONCLUSIONS: These results indicate that the humanistic and economic burden of OA in Ontario is considerable.