Aetna Billing Disputes: Denials, Prior Auth, and Balance Bills

Your EOB and the Aetna Member Portal

Every Aetna coverage decision generates an Explanation of Benefits (EOB). The EOB shows what was billed, what Aetna paid, your cost-sharing responsibility, and—critically—the reason for any denial or reduction.

Access your EOBs at aetna.com under "Claims & EOBs." The portal also shows real-time claim status and lets you initiate appeals online. Download and save the EOB PDF for the claim you are disputing before doing anything else.

On the EOB, locate:

• Reason code: A short description or code explaining why the claim was denied or reduced (e.g., "not medically necessary," "prior authorization required," "out-of-network provider")
• Claim number: Reference this on all correspondence
• Appeals deadline: Aetna prints the filing deadline directly on the EOB for many plans

Filing Aetna's Internal Appeal

You have 180 days from the EOB date to file a Level 1 internal appeal for most commercial Aetna plans. The steps are straightforward:

1. Gather your documents: EOB, itemized bill from the provider, physician letter of medical necessity (if applicable), and any clinical records that support coverage.
2. Write a concise appeal letter: State the claim number, date of service, denial reason cited on the EOB, and why you believe the denial is wrong. One to two pages is enough.
3. Submit: Online at aetna.com, by fax to the number on your EOB, or by certified mail to the appeals address on your EOB. Keep a copy of everything.
4. Track the response: Aetna must respond within 30 days for pre-service appeals and 60 days for post-service claims. Expedited (urgent) appeals get a 72-hour response.

If Aetna upholds the denial at Level 1, you typically have a second internal appeal level before you reach IRO review, depending on your plan type. Check your Summary Plan Description (SPD) or call Member Services to confirm whether your plan requires one or two internal appeal levels.

The IRO External Review Process

After exhausting Aetna's internal appeal levels, you have the right to request independent external review. The IRO is accredited by URAC or similar body and has no financial relationship with Aetna. Its decision is legally binding on Aetna in most states under the ACA and applicable state law.

To request IRO review:

1. Submit a written request to the IRO listed in Aetna's final denial letter, or ask Aetna to provide the approved IRO list for your state.
2. Send the IRO your appeal records, EOBs, physician letters, and clinical documentation. The IRO reviews what you submit—more evidence is better.
3. The IRO must render a decision within 45 days for standard reviews and 72 hours for expedited urgent cases.
4. If the IRO overturns Aetna's denial, Aetna must pay the claim. If the IRO upholds the denial, your next step is a state insurance commissioner complaint or, for ERISA plans, a federal EBSA complaint.

Prior Auth Denials and Peer-to-Peer Review

Prior authorization denials are the most frequent source of Aetna billing disputes. When Aetna denies a prior auth:

• Request a peer-to-peer review immediately. Your physician calls Aetna's medical director to discuss the clinical rationale. This costs nothing and often reverses denials that are based on incomplete information in the file.
• Review Aetna's clinical policy bulletin. Aetna publishes clinical policy bulletins (CPBs) on its website that explain exactly what criteria a service must meet to be covered. Your appeal should address each criterion point by point.
• Submit clinical guidelines. Evidence from peer-reviewed medical journals, specialty society guidelines, or CMS coverage determinations that support the appropriateness of the service strengthen your case significantly.

Common procedures that frequently require Aetna prior auth and face denial include: MRI and advanced imaging, inpatient psychiatric admissions, sleep studies (polysomnography), spinal injections, and specialty biologics.

CVS Health Integration: Pharmacy and Specialty Drug Billing

Since CVS Health acquired Aetna in 2018, pharmacy benefits for most Aetna commercial and Medicare plans are administered through CVS Caremark. This split creates a common source of confusion:

• Medical denials (hospital, physician, outpatient services): Contact Aetna Member Services
• Pharmacy and specialty drug denials: Contact CVS Caremark at 1-800-552-8159 or caremark.com
• Specialty drugs (biologics, infusion therapies, specialty injectables): Handled through CVS Specialty—call 1-800-237-2767

If a specialty drug was denied because it wasn't dispensed through a CVS Specialty pharmacy but you used a different specialty pharmacy your doctor recommended, you may be able to file a network exception request. Ask your doctor's office to submit a medical necessity exception with documentation showing why the alternative pharmacy was used.

Timelines and Key Contacts

• File internal appeal: Within 180 days of EOB date
• Request IRO external review: Within 4 months of final internal denial
• Aetna Member Services (commercial): Number on your ID card; general line 1-888-632-3862
• Aetna Medicare Member Services: 1-800-282-5366
• CVS Caremark (pharmacy): 1-800-552-8159
• CVS Specialty: 1-800-237-2767
• EBSA (ERISA plan complaints): 1-866-444-3272

• Aetna — Appeals and Grievances
• CMS — ACA External Review Requirements
• Department of Labor — EBSA (ERISA Plans)
• CVS Caremark — Pharmacy Benefits