Insurance Denied Treatment? How to Appeal and Use Your Parity Rights

Many families stop at the first “no.” But a denial is a payment decision, and the law lets you challenge it.¹ If the denial came during a review of a stay, see how plans decide how many days to approve.

What should we do first after a denial?

Get the denial in writing, find the deadline, and decide whether it’s urgent. Medicare and Medicaid differ (see below).

1. Get the written notice. Your plan must tell you in writing why it said no. For most private plans, that notice is due within 15 days for a prior authorization request, 30 days for care already received, and 72 hours for urgent cases.²
2. Ask for the criteria. Under the federal parity law, covered plans must give you, on request, their medical necessity criteria for mental health and substance use benefits and the reason for a denial.⁵
3. Talk to the treating program. Ask if its doctor will speak with the plan’s reviewer (a “peer-to-peer” review) and write an appeal letter.
4. Decide if it’s urgent. If waiting could seriously harm their health, ask for an expedited appeal (next section).
5. Ask about money while you wait. Get the program’s answer in writing (see the FAQ below).
6. Get permission to act. If the plan is in your loved one’s name, they can sign a form naming you or their doctor as representative.² See why programs and plans may not talk to you without a release.

How does an urgent (expedited) appeal work?

It’s a faster track for when the normal timeline could seriously put your loved one’s life, or their ability to regain full function, at risk.² If a stay is being cut short, ask the treating doctor whether that standard is met, and to say so in writing.

• You can file the internal appeal and the external review at the same time.²
• The decision must come as quickly as the medical condition requires. It can be given by phone, but written notice must follow within 48 hours.²
• An expedited external review must be decided within 72 hours of the request, or sooner if the medical situation requires it.³

How long do standard appeals take?

For most private plans, an internal appeal takes up to 30 or 60 days, and external review up to 45 more.²³ Mark each deadline on a calendar the day a letter arrives.

What should an appeal include?

A clear request and evidence that answers the plan’s stated reason, point by point. Use the plan’s form, or write a letter with your loved one’s name, claim number and insurance ID number.²

What is an external review?

It’s a review by an independent organization, not the insurance company, and the insurer must accept its decision.³

• What qualifies: denials involving medical judgment, such as “not medically necessary,” denials calling a treatment experimental, and cancellations of coverage over application information.³
• Deadline: a written request within 4 months of the final denial.³
• Cost: free under the federal process run by HHS. Under a state process or a contracted review organization, you may be charged, but no more than $25 per review.³
• How to start: the final denial letter should say who handles your review and how to reach them.³
• Who can file: you can name a representative, such as the doctor.³

Some older “grandfathered” plans may not have to follow these federal appeal rules.⁹ Ask whether yours is one.

How can the parity law help an appeal?

It bars most plans from making addiction care harder to get than comparable medical care. The Mental Health Parity and Addiction Equity Act covers costs such as copays and deductibles, limits on days or visits, and “nonquantitative” rules such as prior authorization, medical management standards, network standards and how out-of-network payment rates are set.⁴⁶ The processes and standards behind those rules must be comparable, and applied no more strictly, for addiction care than for medical care in the same category.⁴

Where parity problems can show up:

• Approval rules. Prior authorization and other medical management rules are covered.⁴ A warning sign: the plan reviews an addiction stay far more often than a comparable inpatient medical stay.
• Facility or location limits. Rules on the type of facility or where it is located are covered by parity standards.⁴
• Out-of-network coverage. If the plan covers addiction care and pays for medical care out of network, it must also offer out-of-network substance use benefits.⁵

Know the limits. The parity law doesn’t require a plan to cover addiction treatment at all, though all Marketplace plans and other non-grandfathered individual and small-group plans must cover it as an essential health benefit.⁴⁶ The federal parity rules don’t apply directly to job-based plans from employers with 50 or fewer employees, though its requirements apply indirectly to many of those plans through the essential health benefit rules.⁴ Plans must document how their rules compare and give that analysis to regulators on request.⁴

What changed in 2025: On May 15, 2025, federal agencies said they would not enforce the new parts of a 2024 parity rule while a court challenge plays out and for 18 months after it ends, and that they are reconsidering the rule, including whether to rescind or change it.⁷ The 2008 law still applies, and plans can still follow the earlier 2013 rules.⁴⁷ Check for newer updates before you rely on the 2024 rule.

Who can help, and where do we complain?

It depends on who regulates your plan. Coverage bought from an insurance company is regulated by your state’s insurance department. Private employer plans that pay claims themselves (“self-funded”) are regulated by the U.S. Department of Labor. Ask the plan administrator which type you have.⁴

Medicare has its own appeal process, generally with five levels, plus a fast appeal if you think covered hospital or certain other services are ending too soon.⁸ For Medicaid, ask your plan or state Medicaid agency how its appeal process works. See Medicare coverage for addiction care and what Medicaid pays for, or start at our insurance hub for the bigger picture.