IntroductionLimited data exists on psychological impacts of the COVID‐19 pandemic among people who use drugs (PWUD). This study aimed to determine the prevalence and correlates of severe psychological distress (PD) among PWUD in Montreal around the beginning of the pandemic.MethodsWe conducted a rapid assessment study from May to December 2020 among PWUD recruited via a community‐based cohort of people who inject drugs in Montreal (Hepatitis C cohort [HEPCO], N = 128) and community organisations (N = 98). We analysed self‐reported data on changes in drug use behaviours and social determinants since the declaration of COVID‐19 as a public health emergency, and assessed past‐month PD using the Kessler K6 scale. Multivariable logistic regression was conducted to examine correlates of PD distress (score ≥13).ResultsOf 226 survey participants, a quarter (n = 56) were screened positive for severe PD. In multivariable analyses, age (1‐year increment) (adjusted odds ratio = 0.94, 95% confidence interval [0.90, 0.98]) and a decrease in non‐injection drug use versus no change (0.26 [0.07, 0.92]) were protective against severe PD, while positive associations were found for any alcohol use in the past 6 months (3.73 [1.42, 9.78]), increased food insecurity (2.88 [1.19, 6.93]) and both moving around between neighbourhoods more (8.71 [2.63, 28.88]) and less (3.03 [1.18, 7.74]) often compared to no change.Discussion and ConclusionsThis study documented a high prevalence of severe PD among PWUD during the COVID‐19 pandemic compared with pre‐COVID‐19 data. Social determinants such as food insecurity and mobility issues, alongside demographic and substance use‐related factors, were linked to distress. Evidence‐based risk mitigation strategies for this population could reduce negative consequences in future pandemics or disruptions.