How to appeal a health insurance denial in Illinois
The short answer
Start with your plan’s own appeal. If the plan says no again, you can usually ask an independent reviewer to decide. Illinois lets you ask an independent reviewer to decide, through Illinois Department of Insurance. The deadline to ask: within 4 months of receipt of your final adverse benefit determination (denial) from the health carrier.
Does this apply to you? State external review covers plans regulated by Illinois: individual and Marketplace plans, and job-based plans your employer bought from an insurer. Many large employers are self-funded; their plans follow the federal external review process, and state law usually does not apply (29 CFR 2590.715-2719(c)(1)). Medicare, Medicaid, TRICARE and federal employee plans have their own appeals: see the plan guides.
External review in Illinois
Within 4 months of receipt of your final adverse benefit determination (denial) from the health carrier
The independent review organization decides as fast as your condition requires and no later than 72 hours after receiving the expedited request. Your provider must submit the physician certification form. In expedited cases the internal appeal and external review rights are exhausted at the same time.
Free
State-regulated plans (insurance bought in Illinois or through an employer that buys insurance). Self-funded employer plans use the federal process.
File with IDOI online (Message Center), by email to DOI.externalreview@illinois.gov, by fax to 217-557-8495, or by mail to 4800 Wabash Avenue, Springfield, IL 62711. Send copies only. Asking for expedited review waives the remaining appeal steps, and you cannot add information afterward, so include everything up front. Self-insured, church, and non-federal government plans, group plans issued in another state, and Medicare, Medicaid, FEHB, and Tricare are not covered. The phone number is IDOI's external review line; the general consumer hotline is 866-445-5364.
Who to contact
- Illinois Department of Insurance
- External review information and forms
- Consumer help line: 877-850-4740
Before external review: the internal appeal
External review usually comes after your plan’s own appeal. The deadline for that first appeal depends on the type of plan:
- Employer plan: 180 days from the day you receive the denial notice
- Marketplace plan: 180 days from the day you receive the denial notice
- Medicare Advantage: 60 days from when you receive the denial (counted as 65 days from the notice date)
- Medicare Part D: 60 days from when you receive the denial (counted as 65 days from the notice date)
- Original Medicare: 120 days from when you receive the notice (counted as 125 days from the notice date)
- Medicaid: 60 days from the date printed on the denial notice
- FEHB (federal employees): 6 months from the date of the denial notice
- TRICARE: Mail within 90 days after the date of the denial notice
Questions people ask
How long do I have to ask for an external review in Illinois?
Within 4 months of receipt of your final adverse benefit determination (denial) from the health carrier
Can I get a fast external review in Illinois?
The independent review organization decides as fast as your condition requires and no later than 72 hours after receiving the expedited request. Your provider must submit the physician certification form. In expedited cases the internal appeal and external review rights are exhausted at the same time.
Does external review cost anything in Illinois?
Free
Do Illinois’s rules apply to my job-based plan?
Only if the plan is fully insured, meaning your employer bought a policy from an insurance company. Self-funded employer plans generally follow the federal external review process instead. Your Summary Plan Description or HR benefits team can tell you which kind you have.
Sources
- Illinois DOI: How to File an External Review
You must file your external review within 4 months of receipt of your final adverse benefit determination (denial) from the health carrier.
- 215 ILCS 180/35 Standard external review
Within 4 months after the date of receipt of a notice of an adverse determination or final adverse determination
- Illinois DOI: Request for External Review form (rev. 6/2026)
You have 4 months to file your external review after receipt of the final denial letter
This page is general information about appeal rules in the United States. It is not legal or medical advice. Rules can change, and your plan’s documents and your denial letter control the dates that apply to you.