Aetna Behavioral Health Appeals in Illinois
Appealing an Aetna behavioral health denial in Illinois means tracking two separate clocks: Aetna's own 30-day Level-1 appeal window, and Illinois's 30-day prompt-payment statute (215 ILCS 5/368b) for clean-claim payment. This guide covers both, plus Aetna's filing address and Illinois's parity protections.
Where to file your Aetna appeal
P.O. Box 14463
Lexington, KY 40512
30 calendar days
60 days from Level-1 denial
1-860-754-2985
Illinois's prompt-payment window
In Illinois, state-regulated (fully-insured) plans — including many Aetna plans — generally must pay or formally respond to a clean claim within 30 calendar days under 215 ILCS 5/368b. This deadline does not bind self-funded ERISA plans. This is a claim-payment deadline, not the appeal-decision deadline. If Aetna missed this window on your claim, cite it as a separate payment violation alongside your Aetna appeal — not as the deadline for the appeal decision itself.
30 days for EFT / 45 days paper for clean claims. Illinois Mental Health and Developmental Disabilities Confidentiality Act applies. BCBSIL is the dominant carrier.
MHPAEA parity for Aetna in Illinois
Illinois adds state-level parity protection
Illinois Section 370c requires coverage for mental and emotional disorders at the same level as physical illness. The Illinois Department of Insurance enforces parity for fully insured commercial plans. Illinois has also enacted prior authorization reform legislation. State enforcement is independent of the May 15, 2025 federal non-enforcement announcement.
Statute: 215 ILCS 5/370c; 215 ILCS 5/368b
Aetna's parity posture: Aetna publishes MHPAEA comparative analyses on request; behavioral health benefits are administered through Aetna Behavioral Health. Document parity violation in detail — Aetna's internal process requires a specific MHPAEA flag in the appeal routing system.
When appealing an Aetna denial in Illinois on a state-regulated, fully-insured plan, cite both federal MHPAEA (29 CFR § 2590.712) and 215 ILCS 5/370c; 215 ILCS 5/368b together — the state statute remains in force regardless of the 2025 federal non-enforcement of the 2024 MHPAEA Final Rule. Self-funded ERISA plans are preempted from state insurance law, so rely on federal MHPAEA alone there.
Common Aetna denial codes
Illinois's insurance commissioner
If your internal Aetna appeal is denied, Illinois's Department of Insurance can help with a complaint or external review for fully-insured plans. Look up the official contact via the NAIC consumer locator.
Note: self-funded ERISA plans are generally exempt from state insurance regulation. If your patient's Aetna plan is employer-sponsored and self-funded, your remedies run through the U.S. Department of Labor (EBSA) rather than Illinois's commissioner.
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Generate my appeal letter →Frequently asked questions
How long does Aetna have to respond to an appeal in Illinois?
Aetna generally has 30 calendar days to respond to a Level-1 appeal. If denied, you have 60 days to request external review. Separately, Illinois's prompt-payment statute gives payers 30 days to respond to a clean claim (215 ILCS 5/368b) — a different deadline governing claim payment, not the appeal decision.
Does MHPAEA apply to Aetna in Illinois?
Generally, yes — for Aetna's group health plans. Federal MHPAEA applies to Aetna's group health plans in Illinois. 215 ILCS 5/370c; 215 ILCS 5/368b additionally applies for state-regulated, fully-insured plans — self-funded ERISA plans are preempted from state insurance law and rely on federal MHPAEA alone; where it applies, Illinois's state law remains in force regardless of the 2025 federal non-enforcement announcement.
Where do I mail or fax a Aetna appeal?
Mail to Aetna Appeals Department, P.O. Box 14463, Lexington, KY 40512. You can also fax to 1-860-754-2985. This address is the same nationally, including for Illinois providers.