Background:Antivirals for the treatment of hepatitis C virus (HCV) infection are effective, but many patients remain untreated and treatment is not yet routine in primary care. We evaluated the characteristics of patients who engaged in HCV treatment, and clinician perspectives on the barriers and facilitators to treatment.Methods:Our mixed-method, parallel-design study was conducted at a multisite primary care centre in downtown Toronto. In a retrospective chart review, we searched records from 2011 to 2017 to collect quantitative data, including HCV infection status and HCV treatment status. To contextualize the data, we conducted in-depth interviews with select physicians between Aug. 1 and Nov. 1, 2017, and analyzed the transcripts using content analysis.Results:Of the 40 381 charts reviewed, 727 patients (1.8%, 95% confidence interval [CI] 1.7%–1.9%) were infected with HCV, and 542 (74.6%) had HCV infection requiring treatment. Of those, 255 patients (47.0%) had engaged in treatment. Patients who had engaged in treatment were more likely to be male (odds ratio [OR] 1.63, 95% CI 1.10–2.42), older (OR 1.04 per year increase in age, 95% CI 1.02–1.05) and housed (OR 2.2, 95% CI 1.36–3.75), and they were more likely not to have engaged in injection drug use (OR 1.87, 95% CI 1.33–2.63). Based on interviews with 8 physicians, treatment barriers included a lack of knowledge about HCV treatment, concerns that patients would not adhere to medications and challenges related to medication access. Facilitators of treatment included access to specialist consultation, pharmacist support and primary care treatment guidelines. Common themes that emerged in both quantitative and qualitative components were the roles of unstable housing and intravenous drug use as barriers to engaging in and completing treatment.Interpretation:Our study captured provider-identified barriers to HCV care and the key factors related to retention in HCV care, including gender, age, housing status and experience with drug use. Successful primary-care-led HCV treatment programs may incorporate specialist and pharmacy support and focus on younger, female, underhoused populations and people who use drugs.