Background: Hepatitis C Virus (HCV) risk is elevated for individuals with an opioid use disorder (OUD). Routine HCV testing is recommended for high-risk individuals, including those with an injection drug use history. HCV antibody testing addresses the first step in the HCV treatment care cascade, with uptake and completion of HCV treatment among individuals with chronic HCV as the optimal care cascade endpoint. The aim of this study was to characterize self-reported HCV treatment cascade outcomes among individuals with an OUD in outpatient medication assisted treatment (MAT). Methods: Individuals receiving methadone or buprenorphine treatment (N = 202, 67.8% female, M age = 35.0, SD = 8.4) completed a brief, anonymous paper-and-pencil survey examining self-reported history of HCV testing, diagnosis, and treatment. Descriptive statistics characterized HCV treatment cascade outcomes. Results: A majority (793%) endorsed a lifetime HCV testing history; 34.9% were tested for HCV during the past year. Of those with a lifetime HCV testing history, 42.7% indicated they have been told they have HCV (n = 67/157), with 21% (n = 14/67) of those individuals reporting that they have been told they have chronic HCV, and 71.4% (n = 10/14) of those with chronic HCV reporting receipt of HCV treatment. Discussion: Results underscore gaps in the HCV care continuum among individuals with OUD in MAT. Interventions to increase uptake of HCV testing, communication of HCV diagnostic and treatment information by medical providers, linkage to HCV medical care, and uptake and adherence to HCV treatment are urgently needed, particularly among individuals with an OUD in MAT. (C) 2017 Elsevier Inc. All rights reserved.