Objectives. We examined the extent of unmet needs and barriers to accessing health care among homeless people within a universal health insurance system. Methods. We randomly selected a representative sample of 1169 homeless individuals at shelters and meal programs in Toronto, Ontario. We determined the prevalence of self-reported unmet needs for health care in the past 12 months and used regression analyses to identify factors associated with unmet needs. Results. Unmet health care needs were reported by 17% of participants. Compared with Toronto's general population, unmet needs were significantly more common among homeless individuals, particularly among homeless women with dependent children. Factors independently associated with a greater likelihood of unmet needs were younger age, having been a victim of physical assault in the past 12 months, and lower mental and physical health scores on the 12-Item Short Form Health Survey. Conclusions. Within a system of universal health insurance, homeless people still encounter barriers to obtaining health care. Strategies to reduce nonfinancial barriers faced by homeless women with children, younger adults, and recent victims of physical assault should be explored.