Your claim was denied, and the clock is already running. Most insurance appeals follow a three-phase path—internal review, formal appeal, and external review—and the first deadline is typically 30 to 180 days from the date on your denial letter. Miss it, and in many states you lose the right to appeal entirely.
This guide walks through the insurance claim appeal process for health, Medicare, auto, and homeowners insurance. The steps are similar across types, but the timelines and your escalation options vary sharply by state and policy. External review—the phase most people don’t know exists—is often your strongest card, and it’s free.
Why claims get denied (and which denials you can actually overturn)
Not all denials are equally contestable. Before you invest hours in an appeal, understand what you’re fighting and whether the insurer’s decision typically holds.
High success rate on appeal:
- Coding or billing errors — claim was submitted with the wrong procedure code, billed to the wrong policy, or duplicated. Resubmission with corrected paperwork often succeeds.
- Pre-authorization confusion — you requested pre-auth and were denied, or the insurer’s records don’t show the request you made. Appeals with proof of the authorization request or emergency context frequently overturn.
Moderate success rate:
- Medical necessity disputes — the insurer’s medical director decided the procedure wasn’t medically necessary under their clinical guidelines (InterQual, MCG, or proprietary standards). Appeals succeed when you present clinical evidence or guidelines showing the insurer misapplied its own criteria.
- Out-of-network provider denials — service was provided by a non-contracted provider. Appeals citing emergency circumstances, lack of in-network alternatives, or ambiguous contract language can win, but the bar is higher.
Low success rate:
- Explicit policy exclusions — the procedure or condition is listed as excluded in your policy document. Unless the exclusion language is genuinely ambiguous or was misapplied, these denials rarely reverse.
- Waiting periods or effective-date issues — service was provided before your coverage began or during a contractual waiting period. These are date-based facts; appeals don’t change them.
Appeal deadlines by insurance type
The insurance appeal deadline is the single most critical date in this process. Federal law sets some minimums; state law often shortens them. The table below shows typical windows, but your denial letter and your state’s Department of Insurance website are the authoritative sources—check both before filing.
| Insurance Type | Internal Appeal Deadline | Insurer Review Time | External Review Available? | External Timeline |
|---|---|---|---|---|
| Health (ACA/employer) | 180 days from denial notice | 30 days (standard); 72 hours (expedited) | Yes (all 50 states) | 30 days (standard); 72 hours (expedited) |
| Medicare (Parts A/B) | 180 days from Notice of Initial Determination | Varies by appeal level | Yes, via Medicare Appeals Council | Varies by stage |
| Auto insurance | 30–90 days (state-dependent) | 15–60 days | Limited (varies by state) | Varies |
| Homeowners/renters | 30–90 days (state-dependent) | 15–60 days | Limited (varies by state) | Varies |
| Life insurance | 30–90 days (state-dependent) | 15–60 days | Rarely available | N/A |
State variation is significant. Pennsylvania, for example, sets a 30-day deadline for most insurance types. California and New York allow longer windows for health insurance. Auto and homeowners deadlines are set by state law or buried in your policy’s fine print. If your denial letter does not clearly state the deadline, call your state insurance commissioner’s office or check their website—every state lists appeals procedures.
What you’ll need
Documents:
- The denial letter (must include reason for denial, policy section cited, and appeal instructions—required by law)
- Your full policy document (not the summary of benefits; the complete contract language)
- Medical records, provider notes, or repair estimates supporting your claim
- Correspondence with the insurer (emails, call logs, prior authorization requests)
- Billing records or invoices showing what was charged and how it was coded
Information:
- The insurer’s clinical guidelines or claims manual (for health insurance medical necessity disputes; sometimes available on the insurer’s provider portal or by request)
- Your state’s external review rules (search “[your state] external review insurance” or visit your state Department of Insurance website)
Prerequisites:
- The denial must have been issued in writing. Verbal claim denials do not start the appeal clock; request written confirmation before the deadline runs.
Phase 1: Internal appeal
The internal appeal is your first formal challenge. You submit a written request asking the insurer to reconsider, and a different claims reviewer (not the person who issued the denial) evaluates it.
How to file
Most insurers accept appeals by mail, email, or online portal. Your denial letter must include instructions; if it doesn’t, call your state insurance commissioner—that’s a regulatory violation.
Write a brief cover letter that includes:
- Your name, policy number, and claim number
- The date of the denial letter
- A one-sentence statement: “I am appealing the denial of [claim description] dated [date].”
- A list of the documents you’re attaching
Attach your supporting evidence. Do not editorialize or argue emotionally. The reviewer is looking for one thing: does the documentation show the insurer misapplied the policy or its own guidelines? If you’re appealing a medical necessity denial, cite the specific clinical guideline or policy section that supports coverage. If it’s a coding error, attach the corrected billing statement.
Submit before the deadline. If you’re close to the deadline and still gathering records, file the appeal on time with what you have and note that “additional documentation will follow within [X] days.” Most states and insurers allow supplemental submissions during the review period.
What happens next
The insurer has 30 days (standard review) or 72 hours (expedited review, for urgent health claims) to respond. The response must be in writing and must explain the decision. If the appeal is denied again, the letter must include instructions for the next phase: formal appeal or external review.
Expedited review is available for health insurance claims when a delay could seriously jeopardize your health. Auto, home, and life insurance typically do not offer expedited timelines.
Phase 2: Formal appeal and external review
If the internal appeal is denied, you have two escalation paths, and which one is available depends on your insurance type and state.
Formal appeal (second internal review)
Some insurers and states require or allow a second level of internal review before external review. This is less common for health insurance under the ACA (which mandates external review after one internal appeal) but may be required for auto, homeowners, or employer plans not subject to federal regulation. Check your denial letter and state Department of Insurance rules.
The process is identical to Phase 1: written submission, supporting documents, and a response deadline (typically another 30 days).
External review (independent third party)
External review is the most powerful tool in the insurance claim appeal process, and most consumers don’t know it exists. An independent reviewer—not employed by your insurer—evaluates your claim based on clinical evidence (for health insurance) or policy language and state law (for other types). The review is free to you; the cost is covered by a state fund or the insurer.
Health insurance: External review is available in all 50 states and the District of Columbia under the Affordable Care Act. You can request it after one internal appeal denial, and the insurer must provide instructions in the denial letter. The independent reviewer’s decision is binding on the insurer in most cases.
Auto, homeowners, life insurance: External review availability varies by state. Some states offer it for unfair claims settlement disputes; others do not. Check your state Department of Insurance website or call their consumer helpline.
To request external review, follow the instructions in your denial letter or contact your state insurance commissioner. You’ll submit the same documentation you used in the internal appeal, plus any new evidence. The reviewer will issue a written decision, typically within 30 days (or 72 hours for expedited health claims).
Why this matters: Insurers often reconsider denials at external review because the reviewer is independent and applies a clinical or legal standard, not the insurer’s cost preference. For medical necessity disputes, the external reviewer often has specialized clinical expertise in the relevant area.
Phase 3: State insurance commissioner complaint
If external review denies your claim or is not available in your state for your insurance type, you can file a complaint with your state Department of Insurance. This is not the same as an appeal, and the commissioner cannot force the insurer to pay your claim. But the complaint creates a regulatory record, and insurers take it seriously.
State insurance commissioners investigate unfair claims settlement practices: unreasonable delays, failure to follow state law, misrepresentation of policy terms, or patterns of bad-faith denials. If the commissioner finds a violation, they can fine the insurer, require corrective action, or refer the case for enforcement. Many insurers settle disputed claims once a state DOI inquiry is opened, to avoid regulatory scrutiny.
Filing a complaint is free and can be done online in most states. Visit the National Association of Insurance Commissioners’ state directory to find your state’s Department of Insurance website and complaint portal.
What NOT to include in your appeal
Appeals are evidence-based, not emotion-based. The following arguments rarely persuade an appeals reviewer and waste space:
- “My doctor says it’s necessary.” This alone is not enough for medical necessity disputes. The insurer’s medical director also has clinical credentials; the question is whether the treatment meets the insurer’s clinical guidelines, not whether your physician believes in it. Cite the guideline or peer-reviewed literature that supports the treatment for your diagnosis.
- “I can’t afford this out of pocket.” Financial hardship is not a coverage argument. The policy either covers the service or it doesn’t; the reviewer cannot override contract terms based on your ability to pay.
- “I’ve been a loyal customer for [X] years.” Loyalty and past claims history do not change whether this specific claim meets policy terms.
- “This is unfair.” Fairness is not the standard. The standard is: does the policy cover this service, and did the insurer apply its own rules correctly?
When to get outside help
You can handle most appeals yourself with the steps above, but two scenarios often warrant professional assistance:
High-dollar claims with complex medical or legal questions. If your claim is worth tens of thousands of dollars and turns on clinical guidelines, state insurance law, or ambiguous policy language, a patient advocate (for health insurance) or a public adjuster (for homeowners insurance) may be worth the cost. Patient advocates typically charge hourly or a percentage of the claim; public adjusters work on contingency. Neither is regulated in all states, so verify credentials.
After external review fails and you’re considering litigation. Small-claims court is an option for claims under your state’s small-claims limit (typically $5,000–$10,000), but the insurer will send a lawyer, and you’ll need to prove bad faith or breach of contract, not just disagreement with the decision. For larger claims, consult an insurance dispute attorney before filing—most offer free initial consultations.
Verify the appeal was received
After you submit your appeal, confirm receipt. If you mailed it, send it certified with return receipt. If you used an online portal, save the confirmation screen. If you emailed it, request a read receipt or follow up within two business days.
If the insurer does not acknowledge receipt within five business days, call the customer service number on your denial letter, reference your appeal submission, and request written confirmation that it was logged. Note the representative’s name, date, and time. Insurers occasionally claim they never received an appeal filed near the deadline; proof of timely submission protects your rights.
FAQ
Can you appeal a denied insurance claim if the deadline has passed?
In most cases, no. Missing the insurance appeal deadline typically ends your right to challenge the denial. A few states allow extensions for “good cause” (serious illness, natural disaster, insurer error), but these are discretionary. If you missed the deadline, call your state Department of Insurance immediately to ask whether an extension or alternative process is available.
How long does an insurance appeal take?
Standard internal appeals are decided within 30 days for health insurance and 15–60 days for auto, homeowners, and life insurance (varies by state and carrier). Expedited appeals for urgent health claims are decided within 72 hours. External review follows similar timelines: 30 days standard, 72 hours expedited for health. The full process—internal appeal through external review—typically takes 60–120 days.
Do insurance companies have to respond to appeals?
Yes. Federal law (for health insurance under the ACA and Medicare) and most state laws require insurers to respond to appeals in writing within a specified timeframe. The response must explain the decision and provide next steps if the appeal is denied. If the insurer fails to respond by the deadline, that is a regulatory violation; file a complaint with your state Department of Insurance.
What is an external review for insurance?
External review is an independent evaluation of your denied claim by a third party not employed by your insurer, appointed by your state insurance regulator. It is available in all 50 states for health insurance and in some states for other insurance types. The reviewer’s decision is binding on the insurer in most cases. External review is free. Learn more at Healthcare.gov’s external review guide.
What are the most common reasons insurance claims get denied?
The most frequent denial reasons are: medical necessity (insurer determines the procedure wasn’t needed), coverage exclusions (service is explicitly not covered), pre-authorization not obtained, out-of-network provider, coding or billing errors, and services provided during waiting periods or before coverage began. The first three are the most commonly appealed.
Insurance appeals are procedural, not personal. The insurer’s denial is not the final word; many appeals succeed, especially coding-error disputes. But success depends on presenting the right evidence at the right phase, and doing it before the deadline. External review is the step most people skip because they don’t know it exists; if your internal appeal fails, use it.
For Medicare-specific appeals, the process has five levels and different deadlines; see CMS’s Medicare appeals guide for the full path. For state-specific appeal rules and deadlines, visit your state Department of Insurance via the NAIC state directory.
Not insurance or financial advice. Coverage rules, appeal deadlines, and regulatory requirements vary by state, insurer, and policy. For guidance on a specific claim, consult your policy document, your state Department of Insurance, or a licensed professional.