Only a small proportion of people with a substance use disorder (SUD) receive treatment. The shortage of SUD treatment providers, particularly in rural areas, is an important driver of this treatment gap. Telemedicine could be a means of expanding access to treatment. However, several key regulatory and reimbursement barriers to greater use of telemedicine for SUD (tele-SUD) exist, and both Congress and the states are considering or have recently passed legislation to address them. To inform these efforts, we describe how tele-SUD is being used.