Unum Mental Health Claim Denied

Mental health parity laws exist precisely for cases like yours — and yet Unum continues to deny mental health and behavioral health claims at rates that would be illegal if applied to physical conditions. If Unum denied your mental health claim, you have strong legal grounds to appeal.

Why Unum Denies Mental Health Claims

Unum's most common denial reasons for mental health claims include:

• "Not medically necessary" — claiming your treatment doesn't meet clinical criteria
• "Exceeded benefit limits" — applying day or visit caps that violate mental health parity
• "Experimental or investigational" — incorrectly labeling standard evidence-based treatment
• "Failure to obtain Prior Authorization Denied: How to Appeal" class="auto-link">prior authorization" — even for emergencies or continuations of care
• "Out-of-network" — when in-network providers aren't available

The Mental Health Parity Laws Unum Must Follow

The Mental Health Parity and Addiction Equity Act (MHPAEA) prohibits insurers from applying more restrictive financial requirements or treatment limitations to mental health benefits than to comparable medical/surgical benefits. If Unum covers 30 days of inpatient cardiac care, they cannot limit psychiatric inpatient to 10 days.

Under ERISA (which governs most employer-sponsored plans), Unum must provide you with:

• A full written explanation of the denial reason
• The specific clinical criteria used
• A description of the appeals process and deadlines

If Unum cited "medical necessity," they must show you the exact InterQual or similar criteria they used — and if those criteria are stricter than for analogous medical conditions, that's a parity violation.

How to Appeal a Unum Mental Health Denial

Step 1: Request the full claim file. Under ERISA, you have the right to receive all documents, records, and other information relevant to your claim — free of charge. Call Unum's appeals line and request this immediately.

Step 2: Get a letter from your treating provider. Your psychiatrist, therapist, or psychologist should write a detailed letter stating:

• Your diagnosis (DSM-5 code)
• Why the denied treatment is medically necessary
• What happens clinically if treatment is denied
• That the treatment follows established evidence-based guidelines

Step 3: Cite MHPAEA in your appeal letter. Explicitly state: "This denial appears to violate the Mental Health Parity and Addiction Equity Act by applying more restrictive criteria to mental health benefits than comparable medical/surgical benefits. Please provide the specific financial requirements and treatment limitations applied to analogous medical/surgical conditions."

Step 4: Submit within Unum's appeal deadline. Unum typically requires appeals within 180 days of denial for ERISA plans. Don't miss this window — once it passes, you lose your right to internal appeal.

Step 5: Escalate if the internal appeal fails. After exhausting internal appeals, you can:

• File an External Independent Review: Complete Guide" class="auto-link">external review with your state's Department of Insurance
• File a complaint with the Department of Labor (for ERISA plans)
• File a complaint with your state's Mental Health Parity Ombudsman (available in many states)

What to Include in Your Unum Appeal Letter

Your letter should specifically address:

1. The exact denial reason Unum provided
2. Clinical evidence contradicting their determination
3. The MHPAEA parity comparison (what Unum covers for analogous physical conditions)
4. Peer-reviewed research supporting medical necessity
5. The risk of harm if treatment is withheld

A well-structured appeal letter citing specific regulations dramatically increases your odds — studies show that appealing a mental health denial succeeds 40–60% of the time when properly documented.

State-Specific Protections

Many states have mental health parity laws that go further than federal MHPAEA:

• California: SB 855 requires coverage of medically necessary mental health treatment based on the same standards as physical health
• New York: Insurance Law §3221(l)(5) mandates parity with no day limits
• Illinois: Insurance Code §370c requires parity plus independent review rights

If your plan is state-regulated (not ERISA), check your state's specific parity laws — they may give you additional appeal grounds.

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Related Reading

• How to Write an Insurance Appeal Letter
• What Is Medical Necessity?
• Internal vs External Insurance Appeal