Aetna Denied Your Claim in Maryland? How to Fight Back

Aetna (CVS Health) serves 22 million members nationally through employer-sponsored HMO, PPO, POS, and ACA marketplace plans. In Maryland, Aetna is a significant carrier — and Maryland has strong mental health parity enforcement, surprise billing protections, and total cost of care regulation that give you meaningful leverage when fighting a denial.

If Aetna denied your claim in Maryland, federal law and Maryland state law both protect your right to appeal. Maryland's External Independent Review: Complete Guide" class="auto-link">external review law (Md. Insurance Code § 15-10B) entitles you to independent review of any adverse coverage decision. The IRO decision is binding on Aetna. Maryland also has a Mental Health and Substance Use Disorder Parity Act (Md. Insurance Code § 15-826) that goes beyond the federal MHPAEA floor, and Maryland Insurance Code § 15-1005 requires Aetna to pay clean claims within 30 days of electronic receipt or 40 days of paper receipt.

Why Aetna Denies Claims in Maryland

Aetna's utilization review systems and medical directors deny claims across consistent categories. In Maryland, the most frequent denial reasons include:

• Medical necessity disputes — Aetna's reviewer determined the treatment does not meet its Clinical Policy Bulletin (CPB) criteria, even when your physician ordered it
• Prior Authorization Denied: How to Appeal" class="auto-link">Prior authorization not obtained — The service required pre-approval that was not secured before treatment, triggering an automatic denial
• Out-of-network provider — The provider is outside Aetna's Maryland network
• Service not covered — The specific treatment is excluded from your plan's benefit design
• Step therapy / fail-first requirement — Aetna requires a less expensive treatment before covering what your doctor recommended
• Mental health parity violations — Aetna applies stricter limits to behavioral health benefits than comparable medical benefits, violating Md. Insurance Code § 15-826
• Coding or administrative error — Incorrect ICD-10 codes, CPT codes, or missing modifiers caused an automatic rejection

Each reason requires a different appeal strategy. Read your denial letter carefully to identify the exact reason cited before building your case.

How to Appeal an Aetna Denial in Maryland

Step 1: Read the Denial Letter and Request Your Claims File

Your Aetna denial letter must include the specific reason for the denial, the plan provision or CPB relied upon, your appeal rights, and your filing deadline. Note the denial reason code and any CPB number — this is your specific rebuttal target.

Under ERISA § 1133 and ACA regulations, you have the right to the complete claims file at no charge. Request it in writing from Aetna member services. It includes internal reviewer notes and medical director opinions, the specific CPB applied to your claim, and any internal guidelines used in the decision. You have 180 days from the denial date to file an internal appeal.

Step 2: Build a Medical Evidence Package

Your appeal stands or falls on the quality of supporting evidence. Gather complete medical records documenting your diagnosis, treatment history, and clinical rationale. Obtain a letter of medical necessity from your treating physician on letterhead, signed, that directly addresses Aetna's stated CPB criteria. For mental health denials, also gather documentation comparing Aetna's behavioral health criteria to the criteria it applies to comparable medical or surgical benefits. Collect peer-reviewed clinical guidelines from specialty medical societies that contradict Aetna's criteria.

Step 3: Write a Targeted Appeal Letter Citing Maryland and Federal Law

Your appeal letter should quote the exact denial reason from Aetna's letter and present a point-by-point rebuttal backed by your evidence. Invoke ACA § 2719 requiring internal appeal and independent external review, with responses within 30 days (standard) or 72 hours (urgent). For employer-sponsored plans, cite ERISA § 1133. If the denial involves behavioral health, invoke MHPAEA § 1185a alongside Md. Insurance Code § 15-826 — Maryland's Mental Health and Substance Use Disorder Parity Act goes beyond federal minimums and is actively enforced by the Maryland Insurance Administration. Cite Md. Insurance Code § 15-10B for external review rights and § 15-1005 for prompt-pay obligations.

Step 4: Submit Through Multiple Channels and Document Everything

Send your appeal via certified mail with return receipt and simultaneously through the Aetna member portal at aetna.com. Keep copies of every document and all delivery confirmations. Aetna must respond within 30 days for standard appeals and 72 hours for urgent cases.

Step 5: Request a Peer-to-Peer Review

Ask your treating physician to request a peer-to-peer review — a direct conversation between your doctor and Aetna's medical director. Many denials are overturned at this stage before formal external review is required. For mental health parity disputes, having a psychiatrist or behavioral health clinician engage directly with Aetna's medical director can be especially effective.

Step 6: Escalate to Maryland Insurance Administration External Review

If Aetna upholds the denial after internal appeal, request an IRO through the Maryland Insurance Administration under Md. Insurance Code § 15-10B. Call (410) 468-2000 or visit insurance.maryland.gov. The IRO decision is binding on Aetna. File a formal regulatory complaint simultaneously, particularly if you suspect a mental health parity violation — the Maryland Insurance Administration investigates these complaints actively. For high-value claims, consult an insurance appeal attorney — ERISA employer plans can be litigated in federal court.

What to Include in Your Appeal

• Aetna denial letter with claim number, denial date, and the specific CPB or plan provision cited
• Complete medical records including physician notes, lab results, imaging, and treatment history
• Physician letter of medical necessity on letterhead, signed, directly addressing Aetna's stated criteria
• For mental health denials: documentation comparing Aetna's behavioral health criteria to its medical/surgical benefit limits
• Peer-reviewed clinical guidelines from specialty medical societies supporting the prescribed treatment

Fight Back With ClaimBack

Maryland's Mental Health and Substance Use Disorder Parity Act and external review rights give you real leverage against Aetna denials. ClaimBack analyzes your specific denial, identifies the strongest rebuttal arguments under Md. Insurance Code § 15-826, § 15-10B, ACA § 2719, and ERISA § 1133, and generates a professional appeal letter in 3 minutes. Start your free claim analysis → Free analysis · No credit card required · Takes 3 minutes

Related Reading

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