Medicaid covers substance use disorder treatment, including both inpatient rehab and outpatient programs, in every state. The process involves confirming your eligibility, finding a facility that accepts Medicaid, and getting through any required approvals. Here’s how each step works and what to expect along the way.
Check Your Medicaid Eligibility
If you already have Medicaid, you can skip ahead. If you don’t, eligibility depends primarily on your income and which state you live in. In states that expanded Medicaid under the Affordable Care Act, adults earning up to 138% of the federal poverty level qualify. For a single person in 2024, that’s roughly $20,800 per year. Coverage extends to adults aged 18 to 64, and eligibility historically includes groups with high treatment needs: low-income women, people with disabilities, and older adults.
In states that did not expand Medicaid, eligibility is narrower. You may need to be pregnant, have a disability, or have dependent children to qualify. If you fall into a coverage gap, your state may still have other options, including block grant funding through the Substance Abuse and Mental Health Services Administration (SAMHSA) that pays for treatment at certain facilities regardless of insurance status.
You can apply for Medicaid through your state’s Medicaid agency website, by phone, or in person at a local office. Many rehab facilities also have intake coordinators who will help you check eligibility and apply if needed. Processing times vary, but most states can determine eligibility within 45 days, and some offer presumptive eligibility that provides temporary coverage while your full application is reviewed.
Find a Facility That Accepts Medicaid
Not every rehab accepts Medicaid, so you need to confirm this before anything else. The most reliable tool is the federal treatment locator at FindTreatment.gov. Enter your address or zip code in the location field, then use the “Sort & Filter” button and select “Medicaid” under the “Payment/Insurance/Funding Accepted” category. This narrows results to facilities that take your coverage.
You can also call SAMHSA’s national helpline at 1-800-662-4357, which is free, confidential, and available around the clock. They can refer you to local programs and help you navigate your options. If your Medicaid plan is managed by a specific insurance company (most are), calling the member services number on your card will get you a list of in-network treatment providers directly.
Understand What Medicaid Covers
Medicaid covers a broad range of addiction treatment services, though the specifics vary by state. Most states cover outpatient counseling, intensive outpatient programs, medical detox (both inpatient and outpatient), and medication for opioid use disorder. Many also cover residential rehab, though this is where things get more complicated.
Medical Detox
Medically supervised detox is covered in most states. As of the most recent data, 32 states cover inpatient detoxification and 34 cover outpatient detoxification. Inpatient detox means you stay at a facility where medical staff monitor your withdrawal symptoms closely, which is particularly important for alcohol and benzodiazepine withdrawal, where complications can be dangerous. Outpatient detox is less disruptive to your daily life and less expensive, but it works best when withdrawal symptoms are expected to be mild to moderate.
Medications for Opioid Use Disorder
Federal law now permanently requires every state Medicaid program to cover all FDA-approved medications for opioid use disorder, along with associated counseling and behavioral therapy. This includes methadone (dispensed through certified opioid treatment programs), buprenorphine (which can be prescribed by office-based providers), and naltrexone (a monthly injection or daily pill that blocks opioid effects). Recent federal guidance also makes clear that a provider cannot deny you medication just because you aren’t simultaneously receiving counseling. Treatment with medication should not be contingent on participating in additional services.
That said, your state or managed care plan may still require prior authorization before covering a specific medication, or may prefer one formulation over another. If you’re prescribed a non-preferred medication, your provider can usually request an exception.
Residential (Inpatient) Rehab
Residential treatment is where Medicaid coverage gets complicated because of something called the IMD exclusion. This is a longstanding federal rule that generally prevents Medicaid from paying for care in residential mental health or addiction facilities with more than 16 beds. To get around this, 26 states have obtained federal waivers allowing Medicaid funds to be used at these larger residential facilities. If your state has a waiver, accessing a 28-day or 90-day inpatient program through Medicaid is much more straightforward. If it doesn’t, your options for residential care may be limited to smaller facilities or state-funded programs outside of Medicaid.
The Prior Authorization Process
For many types of rehab, especially inpatient stays and residential programs, Medicaid requires prior authorization before treatment begins. This means your provider submits clinical information to your Medicaid plan explaining why you need a particular level of care. The plan then reviews it and decides whether to approve coverage.
Many states use the American Society of Addiction Medicine (ASAM) criteria to determine what level of treatment is medically necessary. The ASAM framework describes five broad levels of care, from early intervention and outpatient services up to medically managed inpatient treatment. A clinical assessment will place you somewhere on this spectrum based on factors like the severity of your addiction, your physical and mental health, your living situation, and your history of relapse. The level assigned determines what Medicaid will pay for.
For managed care plans, federal rules currently require standard prior authorization decisions within 14 calendar days and expedited (urgent) decisions within 72 hours. Starting in January 2026, new federal rules will shorten the standard timeline to seven calendar days. If you need treatment urgently, make sure your provider requests an expedited review. Many facilities handle prior authorization on your behalf as part of their intake process, so you don’t necessarily need to navigate this step alone.
What You’ll Pay Out of Pocket
Medicaid has strict limits on what you can be charged. For outpatient services, copays are capped at $4 for most beneficiaries. Inpatient stays can carry a copay of up to $75. Preferred prescription drugs have a copay of up to $4, while non-preferred drugs can go up to $8. The total of all premiums and cost sharing for your household cannot exceed 5% of your family’s monthly or quarterly income, which for most Medicaid beneficiaries means very low total costs.
Some services are exempt from cost sharing entirely, including emergency services and preventive care. And if you cannot afford a copay, providers participating in Medicaid generally cannot refuse to treat you for nonpayment.
Steps to Get Started
- Confirm your Medicaid status. If you’re not enrolled, apply through your state Medicaid office or healthcare.gov. Ask about presumptive eligibility for faster access.
- Search for providers. Use FindTreatment.gov with the Medicaid filter, call SAMHSA’s helpline, or contact your managed care plan’s member services line.
- Call the facility directly. Ask whether they accept your specific Medicaid plan, what levels of care they offer, and whether they handle prior authorization for you.
- Complete an assessment. The facility will evaluate you using clinical criteria (often ASAM-based) to determine the appropriate level of care, from outpatient counseling to residential treatment.
- Let prior authorization proceed. The facility or your provider submits the necessary paperwork. Urgent requests should be decided within 72 hours.
If you’re denied coverage for a particular level of care, you have the right to appeal the decision. Your Medicaid plan is required to explain how to file an appeal in the denial notice. Many denials are overturned when additional clinical information is provided, so don’t treat an initial “no” as a final answer.