Background : Hepatitis C is a viral infection caused by the hepatitis C virus (HCV) with people who inject drugs as the main group at risk worldwide.Aim : This study investigated the differences in uptake for HCV screening and treatment between persons in opioid substitution therapy (OST) and the other members of the Christian Health Insurance Fund in Belgium.Methods : Invoice data were retrospectively collected from the Christian Health Insurance Fund, representing 42% of the healthcare users. Information on demographics, screening, diagnostic tests, treatment and disease progression was obtained from 2008 till 2013. All people in this study were aged 20-65 year. Persons in the OST group were identified as having at least one prescription reimbursed for methadone. This group was compared to the other members of the Insurance Fund not on OST (NOST).Results : The Insurance Fund registered 8,409 unique OST and 3,525,190 members in the general group. HCV RNA screening rate was higher in the OST group after correction for age and gender (4.3% vs. 0.2%). Ribavirin reimbursement, did not differ between the OST and NOST group screened for HCV RNA (16.9% vs. 14.4%), though the probability of having ribavirin reimbursed was smaller for females than for males. Procedures concerning disease progression were reimbursed less frequently in the HCV RNA screened OST group compared to the NOST group (0.3% vs. 1.2%).Conclusion : People on OST were screened more often for HCV RNA. However, the general uptake for HRA screening and treatment in both populations remained suboptimal. ; This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. Acknowledgements This study is part of the ‘Limburg Clinical Research Center (LCRC), supported by the foundation Limburg Sterk Merk, province of Limburg, Flemish government, Hasselt University, Ziekenhuis Oost-Limburg and Jessa Hospital. D.B., N.H. and G.R. are part of the FWO project G0B2317N.