Health Insurance Appeal: How to Challenge a Denied Claim

A health insurance appeal asks your plan to reconsider a decision to deny care or payment. Start with the denial notice, gather evidence that addresses its reason, and submit your appeal before the deadline.

A denial doesn't always mean you'll owe the full bill. It may involve a billing error, a missing record, or a disagreement about whether care was covered.

The first step is to understand why the plan denied the claim and which deadline applies.

1. Read the denial notice and plan documents

Your insurer's denial notice should explain the reason for its decision and your appeal rights. If you've received care, you may also have an explanation of benefits, or EOB, showing what the provider charged and what the plan paid.

An EOB isn't a bill . Compare it with any bill from your provider to understand which service and amount are in dispute.

Find the reason for the denial

Look for the claim number, date of service, provider's name, and denial reason. Common reasons include missing prior authorization, an out-of-network provider, a service the plan considers medically unnecessary, or a coding error.

If the wording is unclear, ask the insurer to explain the denial code and identify the plan provision it relied on. Also ask for the medical criteria used if medical necessity is in dispute. These details help you respond to the actual reason for denial.

Compare the decision with your coverage

Read the relevant section of your policy, benefits booklet, or employer plan's summary plan description. Pay attention to exclusions, referral requirements, prior authorization rules, and coverage limits.

A deductible or coinsurance charge isn't necessarily a denial. If the plan paid according to its terms, you may still owe your usual share. If the service was processed incorrectly, explain the discrepancy in your appeal.

2. Mark the deadlines as soon as you receive the notice

For many private health plans, you have at least 180 days after receiving a denial to file an internal appeal. This is your request for the insurer or plan to take another look at its decision. The Centers for Medicare & Medicaid Services (CMS) describes this deadline in its coverage appeals guidance.

Write down the date you received the notice and the deadline it gives. Keep the envelope or save the electronic notice with your records.

Know when to expect a decision

For standard internal appeals, plans generally must decide within 30 days when you haven't received the requested care. For care you've already received, the general limit is 60 days.

Urgent appeals follow a faster process. Don't wait for the standard timeline if your health could be seriously harmed by a delay.

Keep the internal and external deadlines separate

If the plan upholds its denial, you may have the right to an independent external review. That request has its own deadline, which depends on the review process.

Save the final internal appeal decision as soon as it arrives. It should explain whether external review is available and how to request it. Act promptly even if you already spent time preparing the internal appeal.

3. Gather records that address the denial

The strongest supporting documents depend on why the claim was denied. For a medical necessity dispute, a letter from your treating clinician can explain your diagnosis, the recommended treatment, and why it fits your situation.

For a coding problem, the provider's billing office may need to correct and resubmit the claim. Ask what they plan to do, but keep your appeal deadline in mind while that happens.

Use this document checklist to organize your file:

• The denial notice, EOB, and any related provider bill.
• Your member ID, claim number, date of service, and provider's name.
• The relevant policy language or benefits booklet.
• Medical records, test results, or treatment notes that support the request.
• A clinician's letter and any prior authorization or referral records.
• Copies of calls, messages, and earlier correspondence about the claim.

You don't need every item on this list for every dispute. For example, a network denial may turn on the provider's status on the date of care, while a medical necessity denial may require more clinical detail.

If records aren't ready, submit the appeal within the deadline and ask how to add supporting information. Keep copies of everything you send.

4. Write and submit your internal appeal

Your appeal doesn't need elaborate language. It does need enough detail for the plan to identify the claim and understand what you want changed.

Explain the decision you're challenging

Include your name, member ID, claim number, service date, and the wording of the denial. State that you're requesting an internal appeal and ask the plan to reconsider payment or coverage.

Then explain why you disagree. Point to the relevant plan language and the documents you've enclosed. If your clinician has supplied a letter, refer to the medical reasons it addresses.

You can also ask the plan for the records and criteria it used to make its decision. Access to those materials can help you respond to the insurer's reasoning rather than guess at it.

Follow the notice's submission instructions

Send the appeal using the method and address or portal listed in the notice. If the plan provides a form, include it along with your letter and supporting records. Keep a copy and proof of submission, such as a portal confirmation or delivery receipt.

A doctor or another representative may be able to appeal on your behalf. The plan may require you to authorize that person first. Ask the representative for copies of what they send so you can keep your file complete.

5. Request an expedited appeal when care is urgent

If waiting for a standard decision could seriously jeopardize your life, health, or ability to regain maximum function, ask for an expedited appeal. A clinician can explain why the delay would harm you.

Urgent appeals generally must be decided as soon as your medical situation requires, and no later than 72 hours. You may be able to make the request orally, which can help when time is short. Follow the plan's urgent appeal instructions and document the call.

In an urgent case, you may also request an expedited external review at the same time as the internal appeal. The CMS overview of appeal rights describes how these processes work.

If you're receiving ongoing treatment, talk with your clinician about your immediate care needs while the appeal is pending. An appeal doesn't replace medical advice or guarantee that the plan will approve the service.

6. Ask for external review after an upheld denial

External review puts an eligible denial before an independent reviewer outside your health plan. It can apply to certain disputes involving medical judgment, including some medical necessity decisions. Other denials may not qualify.

Your final internal appeal notice should explain the review route and filing instructions. Depending on the plan, a state process or a federal process may handle the request. Some situations allow you to proceed without finishing the usual internal process, including eligible urgent cases.

Send the decision and supporting evidence

Include the final denial, your original appeal, and the records that support your position. If the insurer gave a new reason for upholding its decision, address that reason and add relevant evidence.

The external reviewer considers the plan's decision independently. If the reviewer overturns an eligible denial, the plan must follow that decision. CMS explains the external appeals framework.

Don't assume every review has the same deadline

The applicable filing period depends on the process handling your case. Under the HHS-administered federal external review process, the request generally must be made within four months after you receive the relevant denial.

Your notice identifies the route for your claim. Submit the request promptly, particularly if you need time to collect additional medical records.

7. Account for the type of private plan

The basic steps are similar across many plans, but the plan's funding and legal status can affect the rules and review route.

Employer-sponsored coverage

Ask your benefits administrator for the plan document and appeal instructions if you don't already have them. The insurer may handle claims for an employer plan, while the employer pays the claims through a self-funded arrangement.

Many employer plans are subject to the federal law known as ERISA. Federal appeal protections also generally apply to non-grandfathered group plans. Your denial notice should identify where to send the appeal and what happens after an internal denial.

Marketplace and other individual plans

For a denied medical claim under a Marketplace plan, appeal the coverage decision to your health insurer. A dispute about Marketplace eligibility or financial assistance is a different process.

Individual plans bought outside the Marketplace can also have appeal rights. However, protections vary for grandfathered coverage and other arrangements, so use the appeal instructions supplied with your policy.

Plan design matters, too. A PPO may cover some out-of-network care, while an HMO often has more limited out-of-network benefits. Referral and authorization rules can differ. Our guide to health insurance networks explains how those differences affect coverage.

8. Use these questions before you send the appeal

A focused conversation with the insurer or provider can uncover missing information. Write down the date, the person's name, and any reference number when you call.

• What exact reason and plan provision support the denial?
• Is the issue medical necessity, network status, authorization, or billing?
• Can the provider correct and resubmit the claim?
• Which documents and medical criteria did the plan use?
• Where should the appeal go, and what is the filing deadline?
• If the denial is upheld, is external review available?

For a medication denial, ask your clinician whether a covered formulary alternative is appropriate or whether they can request an exception. If the exception is denied, the notice should explain the next appeal step. We also explain prescription coverage and formulary exceptions.

9. Follow the claim and the bill

After submitting your appeal, watch for acknowledgment and the written decision. If the plan requests additional information, respond promptly and keep a copy. A late response can slow the review or leave the plan without evidence it needs.

If you receive a bill while the appeal is pending, tell the provider's billing office that the claim is under review. Ask about its billing or payment options, and keep the provider informed when you receive a decision.

An overturned denial doesn't always mean a zero balance. The plan may still apply a deductible, copayment, or coinsurance. Compare the updated EOB with the provider's bill to see how the decision changed your share.

Take the next step with a clear record

A denial is a decision you can challenge. Your best starting point is the notice itself: identify its reason, record the deadline, and gather evidence that answers the plan's concerns.

Keep a complete file through the internal appeal and any external review. That record makes it easier to follow the claim and respond if the plan asks for more information.

If you need help understanding a denial or organizing the next steps, our team offers health insurance paperwork and claims guidance.