Although substance use disorder is a detrimental disease that negatively affects millions of Canadians each year, recovery is possible. Varying factors, however, may impact the likelihood of recovery after the affected individual completes treatment. Understanding the related factors associated with post-treatment outcomes would allow substance use disorder professionals to foster positive outcomes, and if appropriate, provide additional support for individuals in need. This study, therefore, examines the following factors on outcomes six months following discharge from residential substance use disorder treatment: length of stay, completion of treatment, post-treatment 12-Step and other mutual help group attendance, post-treatment drug monitoring, age, gender, and drug of concern. Being male, post-treatment 12-Step and other mutual help group attendance, post-treatment drug monitoring, and treatment completion were found to be significantly related to abstinence at six months following residential treatment. The influence of length of stay in treatment, age, and drug of concern on relapse was found to be insignificant. Utilizing the findings of this study can assist healthcare professionals in promoting recovery for patients with substance use disorder.