Introduction Prevalence of hepatitis C virus (HCV) is substantially higher among prisoners than the general population. In Australia until recently, only a small proportion of prisoners with HCV received antiviral therapy. The direct-acting antivirals (DAAs) for HCV are highly effective, with a low burden of side effects. Since 2016, DAAs are available to all Australians with HCV. However, currently in Australia, they can only be prescribed by or in consultation with experienced prescribers. This study evaluated a telementoring service to upskill doctors and nurse practitioners working in correctional facilities. Methods The telementoring service was implemented in five correctional facilities. Qualitative interviews were used to examine the perceived clinical effectiveness and organisational impacts of the service. Content analysis of the interviews was used to identify key themes. Results In the first ten months of the service, there were 16 telementoring sessions with 173 patients discussed. Sixteen staff participated in qualitative interviews. From these, three key themes were identified: access to antiviral therapy; organisational impacts (cost, increased staff knowledge and confidence, staff time, and workload); and, adaptations of the care model and future opportunities. Conclusion Telementoring is an effective method to facilitate eligible prescriber status to medical doctors and upskill other clinicians in correctional facilities to increase capacity to treat HCV.