Prior Authorization for Rehab

Key takeaway

Prior authorization means the plan confirms that a substance use service is needed before it starts. If the plan covers that care, parity rules limit how much stricter the hurdle can be than the hurdle for other medical care. Keep every letter. A written no is the start of an appeal, not a verdict on you.

Last updated: Mon Oct 05 2026 00:00:00 GMT+0000 (Coordinated Universal Time)

The bed is open, and the plan has not said yes. That wait feels like a judgment. It is a hurdle with a clock. SAMHSA's guide for families defines prior authorization, also called preauthorization, prior approval, or precertification, as a health care professional from your plan confirming that a service is needed before it begins. For substance use treatment, that service might be withdrawal care, a residential stay, or a set of outpatient days. The confirmation is not the same thing as having met your deductible, and it is not a promise that the plan will keep paying if the clinical picture changes.

If the letter has already said no, go to insurance appeals and quote the reason on the page. If someone is in immediate medical danger, call 911. For a mental health crisis, call or text 988. An authorization clock is not an emergency department.

What you are actually waiting on

The plan is being asked whether this service, at this level, for this person, meets its rules before the bill starts. A free bed and an approval are different facts. A program can have a bed and still have no approval. An approval can name fewer days than the program recommended. Ask both questions: is there a bed, and has the plan approved this level of care, for how many days, starting when?

HealthCare.gov says a private insurer must notify you in writing and explain why within 15 days if you are seeking prior authorization, within 30 days for services already received, and within 72 hours for urgent care cases. Those are the clocks on that page. Original Medicare, Medicare Advantage, and Medicare drug plans have their own appeal paths, and the process depends on the kind of coverage. Medicaid authorizations sit with the state program and the managed-care plan. The companion for that card is Medicaid coverage. Do not paste a Marketplace timeline onto a Medicare letter.

If the situation is urgent, say so in the request and ask what the plan treats as urgent. The 72-hour line is for urgent care at the first decision. Faster paths after a denial, including when an outside review can run alongside an internal appeal, are on the appeals guide. Those later clocks have not started if you have not received a denial yet.

Parity limits the hurdle

When a plan covers mental health or substance use benefits, CMS says financial requirements and treatment limitations cannot be more restrictive than the predominant requirements applied to substantially all medical and surgical benefits. The same page says the parity law does not require plans to cover mental health or substance use benefits in the first place.

Prior authorization is one of those treatment limitations. SAMHSA's family guide says the standard for prior authorization of mental health and substance use services must be comparable to, or less restrictive than, the standard for physical health services. A high wall for residential substance use care, and almost no wall for a comparable medical admission, is the kind of comparison parity is about. If the plan denies payment, it must give a written reason and must provide more information on request. You may ask for the plan's comparison of these non-quantitative limits, the category that includes preauthorization. Asking is not the same as winning. Ask what document the plan accepts, and keep a copy of what you sent. Parity rules go further into that comparison.

For non-grandfathered individual and small-group plans, the Affordable Care Act treats mental health and substance use disorder services as an essential health benefit. Marketplace plans cover substance use disorder treatment, and parity applies to tools such as prior authorization. Network rules and medical-necessity review can still apply. A pre-existing substance use disorder is not, on that HealthCare.gov page, a legal reason for a Marketplace plan to deny you enrollment or to charge you more for the plan. That rule is about buying the insurance. It is not an approval of a particular stay.

Deductibles, networks, and the chance that behavioral health is run by a different company than your medical card are on what insurance pays. Call the number on the card that handles behavioral health, not only the number for ordinary doctor visits.

Papers to keep before anyone travels

Keep the written authorization request, or your notes of an oral one, with the date. Keep the plan's written decision, including a partial approval that cuts the days short. Keep the member ID, the subscriber's name if the plan is not in your name, and any reference number. Keep a letter from the treating clinician describing the substance, the withdrawal risk, the level of care, and why a lower level does not fit. Keep notes of phone calls: day, time, the name of the person, and what was said.

Send copies unless the plan requires an original. If someone else files for you, keep any form you signed that lets them do it. Confidentiality rules limit what a program can share with a relative who is trying to help. A helpful relative is not automatically the authorized representative.

Ask, the same day, what happens to the charges if you arrive before the approval, or if the approval ends while you are still there. The HealthCare.gov pages do not say the plan keeps paying for each extra day during a dispute. Ask before a denial, not only after one.

A phone conversation about benefits is not the plan's written authorization, and it is not the final explanation of benefits. If you hear that nothing is on file, treat that as a task. Do not travel on a guess. Questions for admissions include whether the stay needs prior authorization and what you owe if it stops. The license check that belongs beside the money check is how to choose a program. If this plan and this program cannot be matched, FindTreatment.gov is still the federal locator.

Call or text (800) 653-9376 while an authorization is pending, and bring the plan's words rather than a summary from memory.

Additional Resources

Sources cited on this page:

Common Questions

What does prior authorization actually mean?

SAMHSA's parity guide for families says prior authorization, also called preauthorization, prior approval, or precertification, means a health care professional from your plan must confirm that a service is needed before it begins. It is not the same thing as meeting your deductible, and it is not a promise that every day of a stay will stay approved.

How fast must the plan answer?

HealthCare.gov says the insurer must notify you in writing, and explain why, within 15 days if you are seeking prior authorization, within 30 days for services already received, and within 72 hours for urgent care cases. Those clocks are the ones on that page. Medicare and Medicaid use their own rules. Read the letter in front of you before you borrow a timeline from a different kind of plan.

Does parity mean the plan must approve rehab?

No. CMS says the Mental Health Parity and Addiction Equity Act does not require a plan to cover mental health or substance use benefits at all. If the plan does cover them, financial requirements and treatment limits, including tools such as prior authorization, cannot be more restrictive than the predominant limits on other medical care. A plan can still say a service is not medically necessary. That answer can be appealed.

What papers should I keep while I wait?

Keep the request, the plan's written decision, the member ID, and any letter from the clinician. HealthCare.gov also says to keep notes of phone calls, with the date, time, and the name of the person you spoke with. If the decision is a denial, those are the same papers an appeal uses. Send copies unless the plan requires an original.

What if the plan says no?

Start with the appeals steps for your kind of plan. HealthCare.gov describes an internal appeal and, in many cases, an outside review, with deadlines that start from the denial notice. Do not assume the plan keeps paying while you appeal. Ask that question the day the letter arrives. Quote the reason printed on the denial.