Medicaid is the federal-state health insurance program for people and families with low income. Created by the federal government in 1965, Medicaid has grown into the single largest payer of behavioral health and addiction treatment services in the United States.¹ As of January 2025, approximately 71.4 million people were enrolled in Medicaid, according to data from the Centers for Medicare & Medicaid Services (CMS).²

Under the Affordable Care Act (ACA), substance use disorder (SUD) treatment is classified as one of the 10 Essential Health Benefits. All Medicaid expansion programs must cover SUD treatment services, which can include outpatient counseling, intensive outpatient programs (IOP), inpatient detox, residential rehab, and medication-assisted treatment (MAT).³ The Consolidated Appropriations Act of 2024 (CAA 2024) made coverage of medications for opioid use disorder (OUD) a permanent Medicaid requirement, removing a prior sunset date that had been set for 2025.⁴

While federal law sets the baseline guidelines, Medicaid programs are ultimately run by state governments. If you are looking to enroll in Medicaid, you would need to apply through your own state. Many states contract with specific insurance companies to administer their Medicaid plans, and that insurer can answer questions about the details of your coverage.

If you are comparing different programs or figuring out which treatment centers are in network, you can learn more about rehab options⁵ to view facilities aligned with your coverage.