Mental Health Parity and Addiction Equity Act: Coverage and Appeals

The Mental Health Parity and Addiction Equity Act requires health plans that cover mental health and substance use disorder care to do so on terms no worse than the terms they apply to medical and surgical care. That rule reaches your copay, your deductible, and your visit cap, and it reaches the quieter machinery behind a denial: prior authorization, medical necessity criteria, step therapy, and the size and pay of your plan’s provider network. A 2024 final rule, with core pieces phased in through plan year 2026, added data-collection duties and a “meaningful benefits” standard that give you more to work with when something feels off.

Does the Law Apply to Your Plan

Most people with private health coverage are protected. The Act applies directly to large group employer plans, both fully insured and self-funded, under the Employee Retirement Income Security Act,¹ and the same requirements run through the Public Health Service Act for health insurance issuers in the group and individual markets.²

The statute carves out small employers with 2 to 50 employees, but the carve-out is narrower than it looks. The Affordable Care Act requires non-grandfathered individual and small group plans to cover mental health and substance use services as essential health benefits, and those benefits must comply with federal parity rules.³ Parity reaches most small group plans through that pathway.⁴

Non-federal governmental plans covering state, city, and county employees are covered too. These plans used to be able to opt out, but the Consolidated Appropriations Act of 2023 ended that option: no new opt-out elections after December 29, 2022, and existing elections generally could not be renewed after June 27, 2023.⁵ Managed Medicaid plans and certain CHIP arrangements are also covered.

One important boundary: traditional Medicare is not a group health plan or a health insurance issuer, so the Act does not apply to it.⁴ Grandfathered plans that predate the ACA aren’t required to offer mental health benefits at all, but if they do, parity applies to what they offer.

How Parity Is Measured

Parity is not judged across your plan as a whole. Your insurer has to compare mental health benefits to medical benefits within each of six separate classifications: inpatient in-network, inpatient out-of-network, outpatient in-network, outpatient out-of-network, emergency care, and prescription drugs. A plan can’t offset harsh outpatient therapy copays by pointing to generous drug coverage.⁶

Intermediate levels of care, like residential treatment, partial hospitalization, and intensive outpatient programs, have to be slotted into these classifications the same way comparable medical services are. If your plan treats skilled nursing as inpatient, residential treatment for substance use belongs there too; if it treats home health as outpatient, intensive outpatient mental health care belongs there.⁷ Misclassifying intermediate mental health care into a stricter bucket is among the more common violations regulators find.

Cost-Sharing, Visit Caps, and Dollar Limits

These are the numbers on your benefit summary: copays, coinsurance, deductibles, visit limits, and out-of-pocket maximums. Within each classification, the financial requirement or numerical limit a plan applies to mental health benefits cannot be more restrictive than the predominant requirement applied to substantially all medical benefits in the same classification.⁸

In practice, that means a plan can’t charge $50 for a therapy session when a primary care visit is $20. It can’t cap outpatient therapy at 20 sessions a year unless it imposes a comparable numerical cap on outpatient medical visits in that classification. And it can’t impose an annual or lifetime dollar limit on mental health benefits unless it imposes one on substantially all medical benefits.² Pull your Summary of Benefits and Coverage and compare the two columns line by line within each classification. Disparities on the printed page are the easiest violations to spot.

Prior Authorization, Medical Necessity, and Networks

Most real-world denials don’t come from the numbers on the summary. They come from administrative rules, called non-quantitative treatment limitations, that control how care gets approved and paid for. The parity rule here is that the processes, strategies, and evidentiary standards used to apply any such limit to mental health benefits must be comparable to, and applied no more stringently than, those used for medical benefits in the same classification.⁴

Prior Authorization and Step Therapy

If your insurer requires approval before every therapy session but lets most physical therapy visits proceed without pre-approval, that disparity is a parity concern. The Department of Labor flags blanket preauthorization requirements and required written treatment plans as warning signs that call for closer review.⁹ Step therapy, where you have to try a cheaper drug first, isn’t banned, but it can’t be imposed on psychiatric medications under criteria stricter than those applied to medications for physical conditions.

Medical Necessity Criteria

Insurers can’t rely on outdated or unusually narrow clinical guidelines for mental health while using current, flexible standards for surgical or medical care. The criteria used to approve or deny treatment have to be developed with comparable rigor on both sides.

Networks and Provider Pay

A plan that lists plenty of cardiologists and orthopedic surgeons in your area but only a handful of psychiatrists may be creating a structural barrier to care. The methodology used to set reimbursement rates for mental health providers has to be comparable to the methodology for medical providers; paying therapists far less than similarly credentialed specialists discourages them from joining networks, which translates directly into appointments you can’t get.

Under the 2024 final rule, plans now have to collect specific data to back up their network claims: in-network and out-of-network utilization rates, network adequacy measures like travel time and distance, data on providers accepting new patients, and reimbursement rates benchmarked against a reference standard.⁸ If the data show mental health networks lagging behind medical networks, the plan has to take corrective action: raising provider pay, streamlining credentialing, expanding telehealth, or fixing provider directory accuracy.

What Changed Under the 2024 Final Rule

The Departments of Labor, Treasury, and Health and Human Services finalized the rule in September 2024. Most provisions took effect for plan years beginning on or after January 1, 2025. The most significant pieces, including the meaningful benefits standard, the prohibition on discriminatory factors and evidentiary standards, and the data evaluation requirements, apply to plan years beginning on or after January 1, 2026.⁸

The meaningful benefits requirement closes a loophole. If a plan provides any benefit for a mental health or substance use condition in any classification, it must provide meaningful benefits for that condition in every classification where it covers medical conditions, and those benefits must include at least one “core treatment,” defined as a standard treatment indicated by generally recognized independent standards of current medical practice.⁸ A plan can’t nominally cover a condition while offering only token benefits that leave out recognized care.

The rule also treats material differences in access, revealed by the plan’s own data, as a strong indicator of a parity violation. If the numbers look bad, the plan has to take reasonable corrective action and document it, and if the gap persists, explain itself in writing in its comparative analysis.⁸

Getting the Documents Your Plan Has to Share

You have the right to see the medical necessity criteria your plan uses for both mental health and medical benefits. When a claim is denied, the insurer has to give you the specific reason and point to the clinical guidelines that support it.⁸ A denial letter that says “not medically necessary” without citing the standard behind that conclusion doesn’t meet the requirement.

You can also request the plan’s NQTL comparative analysis, which is the document in which the plan shows its work: how it set its administrative limits on mental health benefits and why those limits are no more restrictive than the limits on medical care. Anyone who has received a denied mental health claim can request this analysis, and ERISA participants and beneficiaries may request it at any time.⁸ When a federal agency asks for the analysis, the plan has 10 business days to produce it.¹⁰

These documents are your evidence. If the comparative analysis shows stricter prior authorization for therapy than for physical rehabilitation, or tougher medical necessity standards for substance use treatment than for comparable medical care, you have something concrete to point at.

Appealing a Denied Claim

If a mental health or substance use claim is denied, you can file an internal appeal. For ERISA-governed employer plans, you generally have 180 days from the date of the denial. The plan has to assign a reviewer who was not involved in the original decision and who gives no deference to it.¹¹

Response timelines depend on the type of claim. Urgent care decisions are due within 72 hours. Pre-service claims (approval before treatment) must be decided within 15 days per level of review. Post-service claims (disputing a bill for care you’ve already received) allow the plan up to 30 days per level.¹¹ Reference the parity law by name in your appeal and ask the plan to show that the same limitation would apply to a comparable medical claim. That framing forces the reviewer to answer the parity question directly instead of restating the original denial.

If the internal appeal fails, you can take the dispute to external review by an independent reviewer who isn’t bound by your insurer’s own medical necessity guidelines. The federal external review process through HealthCare.gov has no filing fee, and state-run external review programs are legally capped at $25.¹²

Where to Report a Violation

Which agency handles your complaint depends on who runs your plan. For private employer-sponsored plans, both fully insured and self-funded, enforcement sits with the Department of Labor’s Employee Benefits Security Administration. You can reach a benefits advisor at askebsa.dol.gov or 1-866-444-3272.¹³

For non-federal governmental plans covering state, city, or county employees, enforcement sits with CMS. The number is 1-877-267-2323 (extension 6-1565), and the email is phig@cms.hhs.gov.⁴

Fully insured plans are also regulated by your state insurance department. State regulators can fine carriers, require them to reprocess denied claims, and order coverage adjustments when they find patterns of noncompliance. Investigations at either level often involve pulling the insurer’s internal manuals and audit logs to see whether mental health claims are actually being processed under the same standards as medical claims. A single well-documented complaint can prompt a review that fixes problems for every member of the plan.

1
Office of the Law Revision Counsel. 29 USC 1185a – Parity in Mental Health and Substance Use Disorder Benefits
2
Office of the Law Revision Counsel. 42 USC 300gg-26 – Parity in Mental Health and Substance Use Disorder Benefits
3
ASPE. Affordable Care Act Expands Mental Health and Substance Use Disorder Benefits and Federal Parity Protections
4
Centers for Medicare & Medicaid Services. Mental Health Parity and Addiction Equity Act (MHPAEA)
5
Centers for Medicare & Medicaid Services. Insurance Standards Bulletin Series – Sunset of MHPAEA Opt-Out Provision for Self-Funded Non-Federal Governmental Group Health Plans
6
U.S. Department of Labor. FAQs for Employees About the Mental Health Parity and Addiction Equity Act
7
U.S. Department of Labor. Self-Compliance Tool for the Mental Health Parity and Addiction Equity Act (MHPAEA)
8
Federal Register. Requirements Related to the Mental Health Parity and Addiction Equity Act
9
U.S. Department of Labor. Warning Signs – Plan or Policy Non-Quantitative Treatment Limitations (NQTLs) That Require Additional Analysis to Determine MHPAEA Compliance
10
U.S. Department of Labor. Final Rules Under the Mental Health Parity and Addiction Equity Act
11
U.S. Department of Labor. Benefit Claims Procedure Regulation FAQs
12
HealthCare.gov. External Review
13
U.S. Department of Labor. Mental Health and Substance Use Disorder Parity Investigations and Enforcements