How to Appeal a Mental Health Insurance Denial — Complete 2026 Guide

Your insurance denied coverage for therapy, inpatient psychiatric care or another mental health service. This happens far more often than it should — and the denial is not always the final word.

Appealing a mental health insurance denial is your legal right. And with the right approach, a significant percentage of appeals succeed.

Why Mental Health Claims Are Denied

Insurance companies deny mental health claims for several common reasons:

Not medically necessary: The most common reason. The insurer determined the treatment was not medically necessary — even if your provider ordered it.

Prior authorisation not obtained: Some mental health treatments require pre-approval. If your provider did not obtain this, the claim may be denied.

Benefit limit reached: Your plan imposes a limit on covered sessions and you have reached it. Under mental health parity law, these limits must be comparable to medical benefits.

Out-of-network provider: You saw a therapist outside your insurance network without out-of-network benefits.

Mental health parity violation: Your plan is treating mental health benefits less favourably than comparable medical benefits — which is illegal under federal law.

Your Rights Under Mental Health Parity Law

The Mental Health Parity and Addiction Equity Act (MHPAEA) prohibits insurance plans from:

• Imposing more restrictive session limits on mental health than on comparable medical services
• Charging higher copays or deductibles for mental health than for comparable medical services
• Applying stricter prior authorisation requirements to mental health than to comparable medical services
• Using more restrictive medical necessity criteria for mental health than for physical health

If your denial appears to violate parity — you received different treatment for mental health than you would for a comparable physical health condition — this is a powerful basis for your appeal.

Step 1 — Request the Denial Reason in Writing

If you have not received a written denial letter, request one. The letter must include:

• The specific reason for the denial
• The specific plan provision or clinical criteria used
• Instructions for appealing

Step 2 — Request the Clinical Criteria Used

Request the specific clinical criteria your insurer used to determine your treatment was not medically necessary. You are entitled to this under ACA regulations.

Call and say: “I received a denial for [service] and I am preparing an appeal. I need the complete clinical criteria and guidelines your company used to make this determination.”

Step 3 — Get a Letter of Medical Necessity

Ask your therapist or psychiatrist to write a detailed letter of medical necessity explaining:

• Your diagnosis
• Why the specific treatment is medically necessary
• Clinical guidelines supporting the treatment
• What would happen without this treatment
• Your treatment history and response

This letter is the most powerful document in your appeal.

Step 4 — File Your Internal Appeal

Use this template:

“[Your Name]
[Date]
[Insurance Company] Appeals Department

Re: Appeal of Mental Health Claim Denial
Claim Number: [X]
Date of Service: [Date]
Provider: [Provider Name]
Service Denied: [Description]

Dear Appeals Department,

I am writing to formally appeal the denial dated [date] for [service]. Your denial states [denial reason].

I respectfully dispute this determination for the following reasons:

1. [Address the specific denial reason with clinical evidence]
2. [Reference mental health parity if applicable — compare to how a similar physical health condition would be treated]
3. [Reference your therapist’s letter of medical necessity]

Under the Mental Health Parity and Addiction Equity Act, my plan cannot impose restrictions on mental health benefits that are more restrictive than those applied to comparable medical benefits.

Enclosed: Letter of medical necessity from [Provider], relevant medical records, clinical guidelines supporting this treatment.

Please overturn this denial and process this claim.

Sincerely,
[Your Name]”

Submit by certified mail. Keep copies of everything.

Step 5 — Request External Review If Appeal Fails

If your internal appeal is denied, request independent external review. An independent reviewer — completely separate from your insurer — reviews your case and issues a binding decision.

For mental health parity violations specifically, contact:

• Your State Insurance Commissioner
• The Department of Labor Employee Benefits Security Administration (EBSA): 1-866-444-3272
• The ERISA Advisory Council for employer-sponsored plans

Step 6 — File a Mental Health Parity Complaint

If you believe your denial violates mental health parity law, file complaints with:

• Your State Insurance Commissioner
• The Department of Labor: dol.gov/agencies/ebsa/about-ebsa/our-activities/resource-center/fact-sheets/mhpaea
• CMS: cms.gov/CCIIO/Programs-and-Initiatives/Other-Insurance-Protections/mhpaea_factsheet

Parity violations are taken seriously by regulators — complaints create regulatory pressure and often result in denied claims being reconsidered.

Frequently Asked Questions

How long do I have to appeal a mental health insurance denial?
Most plans require internal appeals to be filed within 180 days of the denial. Check your denial letter for the specific deadline — missing it can permanently waive your right to appeal.

What if my insurer says my therapy is not medically necessary?
Request the specific clinical criteria used to make this determination. Then have your therapist write a detailed letter explaining why your treatment meets those criteria. Clinical guidelines from the American Psychological Association (APA) or relevant professional bodies can support your case.

Can I continue therapy while my appeal is pending?
Yes — particularly if you are in the middle of an approved course of treatment. Under ACA rules, if your plan is terminating ongoing treatment, you have the right to continue at no additional cost while the appeal is pending.

Medical Disclaimer: Information on TherapyInsuranceGuide.com is for educational purposes only and does not constitute legal advice. Always consult qualified professionals for advice specific to your situation.