The Canadian Institute for Health Information (CIHI) is responsible of compiling public and private spending in various sectors of the healthcare system in the different provinces. These data seem to indicate that Quebec is the province that spends the lowest on public health. However, this finding may be inaccurate, as definitions of public health differ from one jurisdiction to another. So, after defining public health and its components, this report analyzes the Quebec government's categorization of the various public health programs. Although this categorization is fairly precise, we have identified programs that fit within our definition of public health, but which are not considered as such by the Quebec government. This exercise enables us to re-evaluate public health spending in Quebec, and to arrive at a level of expenditure similar to that reported by CIHI. Using these same categorizations, we compare public health spending in Quebec with that in Alberta, British Columbia and Ontario. This comparison reveals that CIHI tends to overestimate public health spending in all provinces except Quebec. Thus, our public health measure arrives at similar levels of public spending between provinces, and suggests that Quebec is not the lowest-spending province. By aligning public spending levels across provinces, this study offers a renewed perspective on Quebec's public health efforts.