BackgroundSolitary use of substances is a risk factor for substance use-related mortality. Novel e-health harm reduction interventions such as virtual overdose monitoring services (VOMS) have emerged in North America to improve access to emergency overdose support for people who use substances (PWUS). To date, little research has been published, and the perspectives of PWUS are needed to inform evaluation and policy efforts.ObjectiveTo explore the beliefs, values and perceptions of PWUS around using and accessing VOMS in Canada.MethodsA qualitative study following grounded theory methodology was conducted. Using existing peer networks, purposive and snowball sampling was conducted to recruit PWUS (≥ 18 years) with previous experience with VOMS. Thematic analysis was used to analyze twenty-three interviews. Several methods were employed to enhance rigor, such as independent data coding and triangulation.ResultsTwenty-three one-on-one telephone interviews of PWUS with previous experience with VOMS were completed and analyzed. The following themes emerged: (1) feelings of optimism around VOMS to save lives; (2) privacy/confidentiality was highly valued due to stigma and fear of arrest; (3) concerns with reliable cell phones negatively impacting VOMS uptake; (4) concerns around emergency response times, specifically in rural/remote communities; (5) desire for trusting relationships with VOMS operators; (6) importance of mental health supports and referrals to psychosocial services; and (7) possible limited uptake due to low public awareness of VOMS.ConclusionThis qualitative study provided novel insights about the VOMS from the perspectives of PWUS. PWUS generally felt optimistic about the potential of VOMS as a suitable harm reduction intervention, but several potential barriers around accessing VOMS were identified that may limit uptake. Future research is warranted.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12954-023-00807-9.