Efforts to increase the number of people having hepatitis C virus (HCV) treatment require understanding how to best deliver services to meet consumers' needs. The general health literature has examined the role that partners can play in supporting health outcomes. This study examines the experiences of couples who inject drugs in relation to knowledge of, decisions about and management of HCV treatment. This is a qualitative interview study of people who inject drugs in couples. Participants were recruited from harm reduction services in two major Australian cities. Couples were interviewed separately. Data were examined using the couple as the unit of analysis and to identify patterns of experience related to the HCV serostatus of couples. Knowledge of HCV and HCV treatment was low and variable but showed some relationship to serostatus. Decisions about HCV treatment were deeply informed by concerns regarding treatment side effects. Positive concordant couples considered 'staging' treatment to ensure that each partner could (in turn) care for the other. People with HCV in serodiscordant relationships may need specific support regarding HCV treatment information. Within positive concordant partnerships, our data indicated the need to support the HCV-positive 'carer' during their partner's treatment. Changing treatment regimens, and their anticipated lower side effect profiles, will need to be actively promoted to ensure that couples understand how these changes affect their treatment options.