Abstract Background Although there is indisputable evidence that supervised consumption services (SCS) help to keep people safe and decrease significant harms associated with substance use, the Canadian public often holds divergent and polarized views towards SCS. Polarized perspectives can be resistant to evidence and can prevent productive discourse that might otherwise lead to better public health services and outcomes. Objective The main objective of the study was to determine the degree to which individuals' moral foundations predict attitudes toward SCS and whether attitudes are impacted by stigmatizing views of, and proximity to, people who use drugs. Methods The study was based upon conceptual frameworks related to moral foundations theory (MFT), stigma, and personal experience with people who use drugs (PWUD), using associated instruments to determine alignment with public attitudes towards SCS. A series of hierarchical multiple linear regression analyses were employed to identify variables that significantly predict support for SCS. Results The panel sample comprised 2116 participants from the three prairie provinces in Canada (Manitoba, n = 716; Saskatchewan, n = 700; and Alberta, n = 700). Higher scores on the Harm/Care and Fairness/Reciprocity subscales were associated with higher levels of support for SCS. Conversely, higher scores on the Authority/Respect and Purity/Sanctity subscales predicted lower levels of support for SCS. Greater support for SCS was found to be predicted by lower levels of stigma towards people who use drugs. Overall, participants from Alberta and Saskatchewan were less supportive of SCS than those from Manitoba, although Manitoba lacked an SCS at the time of the study. Conclusion The results enhance our understanding of factors that predict support levels for SCS among the public in Canada’s Prairie Provinces. These findings can inform researchers, policy and decision-makers in developing strategies for bringing the public on board to increase the acceptance of SCS in their communities by specifically addressing underlying concerns that may not be overtly articulated by those with opposing views.