Purpose: Factors underlying food-purchasing decisions were examined among a sample of low-income Toronto families. Methods: A cross-sectional survey was completed among 485 families residing in high-poverty Toronto neighbourhoods. Food-security status was assessed using the Household Food Security Survey Module. Open-ended questions were included to examine respondents’ food selection and management practices and their purchasing decisions for six indicator foods. Logistic regression was used to examine associations between factors influencing food-purchasing decisions, perceived food adequacy, and severity of food insecurity. Results: Twenty-two percent of families had been severely food insecure in the past 30 days. Respondents engaged in thrifty food shopping practices, such as frequenting discount supermarkets and budgeting carefully. Price was the most salient factor influencing food-purchasing decisions; the likelihood that families would report this factor increased with deteriorating food security. Preference, quality, and health considerations also guided food-purchasing decisions, but generally to a lesser extent as food insecurity increased. Household food supplies reflected constraints on food purchasing, and they diminished with increasing food insecurity. Conclusions: Despite their resourcefulness, low-income families struggle to feed their families. Dietitians have an important role to play as advocates for adequate income supports to promote food security and nutritional health.