Federally certified opioid treatment programs (OTPs) provide psychosocial counselling in addition to medications for opioid use disorder (MOUDs) using a patient-centered approach in providing substance use disorder treatment. This study explored factors associated with patients' adherence to counselling while receiving MOUD at an OTP. A retrospective cohort design using data on adult patients (n = 1151, 61% females, 39% males) admitted to an OTP from July 1, 2014, to June 30, 2016, was employed. The data were for single episodes of care up to 52 weeks. Survival analysis (cox proportional hazards regression) assessed the relationship of personal characteristics, socio-economic status, payment for services, type of substance use, comprehensive care and social support with counselling for up to a year. Results indicated that age, having services paid for by public means, was associated with counselling adherence. Primary heroin use patients had a higher risk of counselling adherence failure than patients who primarily used non-medicinal prescription substances. Treatment agencies may benefit from funding and using evidence-based practices for primary heroin use patients and young adults to better engage and retain these populations in treatment.