How to Appeal an Insurance Denial for ABA Therapy (Step by Step)

The Direct Answer

New York, New Jersey, and North Carolina all have laws that require insurance plans to cover ABA therapy for children with autism diagnoses. Federal mental health parity law also applies to most employer-sponsored plans. If your insurer has denied ABA coverage, there is a strong legal foundation for your appeal.

Why Insurance Denials Happen

Before you can appeal effectively, you need to understand why the denial was issued. The most common reasons include:

• Not medically necessary: The insurer determined that ABA isn't required or that a lower level of care is sufficient.
• Missing documentation: The BCBA or provider didn't submit enough clinical information to support the request.
• Out-of-network provider: The provider isn't in-network and the plan doesn't cover out-of-network services at the same level.
• Benefit exclusion: The plan claims ABA therapy isn't a covered benefit (less common now due to state mandates, but still occurs).
• Hours not authorized: The number of hours requested was denied, even if some ABA coverage exists.

Each denial reason has a different appeal strategy. Reading the denial letter carefully is the essential first step.

Step 1: Request the Denial in Writing and Read It Carefully

Call your insurance company and ask for the denial in writing if you haven't already received a formal letter. The denial letter must explain the specific reason for denial and your rights to appeal. Look for:

• The specific reason cited (medical necessity, benefit exclusion, etc.)
• The clinical criteria the insurer used to make the decision
• Your internal appeal deadline (usually 30–180 days from the denial date)
• The name of the medical reviewer who denied the claim

Step 2: Get a Letter of Medical Necessity

A Letter of Medical Necessity (LMN) is the most important document in your appeal. It should come from your child's BCBA and/or their diagnosing physician, and it should specifically address the reason the insurance company gave for denial.

A strong LMN includes:

• Your child's diagnosis and severity level (DSM-5 Level 1, 2, or 3)
• Specific functional impairments — what your child cannot do because of autism that ABA would address (communication, self-care, safety awareness, behavioral dysregulation)
• The clinical rationale for why ABA therapy is appropriate and medically necessary for this specific child
• The recommended hours and rationale for why that level of intensity is needed
• Reference to peer-reviewed research supporting ABA for children with your child's profile
• Statement of what happens if treatment is denied — what skills won't develop, what behaviors will likely escalate

Step 3: File the Internal Appeal

Submit your appeal in writing (certified mail or through the insurer's online portal, keeping a copy). Your appeal package should include:

1. A cover letter summarizing why the denial was incorrect
2. The Letter of Medical Necessity from your BCBA and/or physician
3. Copies of your child's diagnosis report and any assessment results
4. Any progress notes or clinical data from current providers
5. Relevant state law citations (see below)

Step 4: If the Internal Appeal Fails — Request an External Review

If your internal appeal is denied, you have the right to request an independent external review. In an external review, an independent physician or clinical reviewer — not employed by your insurance company — evaluates the denial and makes a binding decision. Insurers are required to follow the external reviewer's ruling.

External reviews are free to you and typically resolve within 30–45 days (or sooner for urgent situations). To request one:

• Ask your insurance company directly for the external review process
• In New York, you can request through the NY Department of Financial Services (DFS)
• In New Jersey, contact the NJ Department of Banking and Insurance (DOBI)
• In North Carolina, contact the NC Department of Insurance

Step 5: File a Complaint with Your State Insurance Department

At any point in this process, you can also file a formal complaint with your state insurance regulator. This is especially useful if you believe the insurer is violating state autism coverage mandates or not responding to your appeals in good faith. Regulators take these complaints seriously and can investigate patterns of improper denials.

Getting an ABA Provider Started While You Appeal

The appeal process can take weeks or months. In the meantime, ask your ABA provider about a few options: starting services while appealing with a payment arrangement, requesting expedited review if your child's situation is urgent, or asking whether they can see your child under a different benefit (some services may qualify under different coverage categories).

Match Care ABA helps families in NY, NJ, NC, and CO find ABA providers who are experienced with insurance navigation and are currently accepting new clients.