Background Methadone maintenance therapy remains the most common form of substitution therapy for opioid use disorder in Canada. Effectiveness of methadone maintenance therapy has been established, but recently newer treatment delivery models have emerged. Differences across these treatment models have not been examined. Purpose This descriptive qualitative study used semi-structured interviews to assess client experiences in three methadone maintenance therapy treatment delivery models: (a) comprehensive programs, (b) low-threshold/high-tolerance programs, and (c) fee-for-service programs. Methods A total of 32 participants were recruited from methadone maintenance therapy clinics in an Atlantic Canadian city and grouped into three models of care (na = 9, nb = 11, nc = 12). Content analysis was performed on interview data to assess the frequency of relevant themes in the data. Results Participants from all groups stressed the importance of supportive staff and having access to some form of counselling. However, low-threshold/high-tolerance and fee-for-service clients voiced a need for more formal counselling and programming at their clinics. Methadone was reported as the most helpful aspect of the methadone maintenance therapy programs; however, participants also expressed negative views about the substance. Conclusions These findings have important implications for the development and implementation of methadone maintenance therapy, specifically pertaining to further integration of addiction and mental health services.