Health Insurance Claim Denied? How to File an Appeal and Meet the Deadlines

• In the United States, you can usually ask your health plan to reconsider a denied claim through an internal appeal, and many denials can later go to independent external review.
• Start with the denial notice, check the filing deadline, request the records behind the decision, and add supporting information from your doctor or provider.
• Urgent cases may qualify for an expedited appeal, while Canadian consumers generally follow their insurer’s complaint process and then contact OLHI or their provincial or territorial regulator.

What to do when your health insurance claim is denied

Yes, you can often appeal a denied health insurance claim. The first step is to read the denial notice carefully and follow the appeal instructions in that document. Your insurer should explain why it denied the claim, identify the applicable plan rule, and tell you how and when to challenge the decision.

This article focuses mainly on private and employer-sponsored health coverage in the United States. Marketplace plans use the same basic internal-appeal and external-review concepts, but the exact instructions and deadlines can depend on your plan, state, and the reason for the denial.

Do not rely on a phone representative’s verbal promise that the issue will be fixed. Ask for the appeal instructions in writing, keep copies of everything, and record the date, time, and name of anyone you speak with.

First, identify why the claim was denied

A denial is not always a final answer. Insurers may reject a claim because the service was considered medically unnecessary, required prior authorization, was provided by an out-of-network provider, was coded incorrectly, was excluded by the plan, or lacked supporting medical records.

Look for the denial reason, claim number, date of service, denial code, appeal deadline, mailing address, fax number, online submission instructions, and information about external review. If the denial resulted from a simple coding or billing error, ask the provider to submit a corrected claim as well as considering an appeal.

For an employer plan, review the Summary Plan Description and the plan’s claims procedures. Federal employee-benefit rules generally give participants at least 180 days to appeal a denied claim, although your plan documents may provide additional details or a longer period.

Who can appeal a denied health insurance claim?

In the U.S., the person covered by the plan can usually file the appeal, and a healthcare provider, family member, attorney, or patient advocate may be able to act as an authorized representative. Check whether the insurer requires a signed authorization form.

The rules can differ depending on how you get coverage:

• Marketplace plan: Follow the appeal instructions from your insurer. A denial of a medical claim is generally appealed to the plan, not through a Marketplace eligibility appeal.
• Employer-sponsored plan: Use the claims and appeals procedure in the Summary Plan Description. Some plans require two internal appeal levels.
• Individual plan bought directly from an insurer: Follow the policy’s appeal instructions and your state’s insurance rules.
• Medicare, Medicaid, or a state-specific program: Use that program’s separate appeal process and deadlines rather than assuming the commercial insurance rules apply.

In Canada, the process is different. Private health and travel insurance complaints generally begin with the insurer’s internal complaint process. If the issue is not resolved, consumers can contact the OmbudService for Life and Health Insurance or their provincial or territorial insurance regulator. Publicly funded provincial and territorial health coverage has its own review and appeal rules.

Gather the documents before filing

A strong appeal connects the denied service to the coverage your plan provides. You do not need a dramatic letter; you need a clear explanation supported by records.

• The denial letter or explanation of benefits
• Your insurance ID, claim number, and date of service
• The relevant page from your policy, Summary of Benefits and Coverage, or Summary Plan Description
• Medical records, test results, treatment history, or prescription information
• A letter of medical necessity from your doctor or other qualified provider
• Evidence that prior authorization was requested or that the insurer gave misleading instructions
• Corrected billing or procedure codes from the provider, if coding may be the problem
• Any peer-reviewed or clinical information your doctor believes supports the treatment

Ask the plan for copies of documents, records, and other information relevant to the denied claim if they were not included with the notice. Employer plans covered by federal benefits rules generally must provide relevant claim information free of charge when you request it.

How to file an internal appeal in the United States

An internal appeal asks the insurance company to reconsider its own decision. Use the insurer’s form if one is provided. If there is no form, send a signed letter that clearly says you are appealing the denial.

Include your name, address, member ID, claim number, date of service, the service or treatment in dispute, the reason you believe the denial should be reversed, and a list of the documents attached. Ask the insurer to review the claim under the correct plan provision and request written confirmation that it received your appeal.

Submit the appeal through the method in the denial notice. If you mail it, use a trackable service. If you fax or upload it, save the confirmation page or electronic receipt.

Typical internal-appeal decision times

Your plan documents and denial notice control the exact procedure. Employer plans may have different timing details, particularly when they require more than one internal appeal.

What changes if the situation is urgent?

Ask for an expedited appeal if waiting for the standard process could seriously endanger your life, health, ability to regain maximum function, or ability to manage severe pain. Your doctor may need to explain why the ordinary timeline is medically unsafe.

In qualifying urgent situations, you may be able to request an expedited internal appeal by phone. You may also be able to begin an external review at the same time instead of waiting for every internal appeal step to finish.

How external review works

If the insurer upholds the denial after the internal appeal, you may be entitled to an external review by an independent organization. The external reviewer—not the insurance company—examines whether the denial should stand.

External review commonly applies when the denial involves medical necessity, appropriateness of care, the healthcare setting or level of care, effectiveness of a covered benefit, experimental or investigational treatment, or certain coverage cancellations. It may not apply to every dispute, such as a straightforward eligibility or premium-payment issue.

The deadline is especially important. Federal guidance commonly provides at least 60 days after the final denial for an external-review request, while some federal processes allow four months and some state or plan rules may provide more time. Use the deadline printed in your final denial notice rather than relying on a general timeframe.

If the plan is subject to the federal HHS-administered external-review process, a standard review is generally decided within 45 days. An expedited external review is decided as quickly as the medical situation requires and generally within 72 hours after the request is received. Other plans may use a state or plan-specific external-review process with different instructions.

When an external reviewer overturns a denial covered by the applicable process, the insurer generally must accept that decision. Keep in mind that an external review is not a guarantee of payment; the reviewer considers the plan terms, medical evidence, and the reason for the denial.

What happens after you submit the appeal?

Save the submission confirmation and watch for a written decision. The decision should explain whether the denial was reversed, partially reversed, or upheld. If the insurer asks for more information, respond by the stated deadline and keep proof of what you sent.

If the insurer misses the required deadline, fails to follow its own appeal procedure, or refuses to provide relevant information, document the problem. You may be able to ask for external review without completing every internal step, depending on the plan and applicable law.

If the appeal succeeds, confirm how the insurer will reprocess the claim, update the explanation of benefits, and pay the provider or reimburse you. If you still owe a bill, tell the provider that the claim is under appeal and ask whether collection activity can be paused while the review is pending.

Canada: where to take a denied private health claim

Canada does not have one nationwide private-health-insurance appeal deadline that applies to every policy. Start by following the insurer’s complaint process and ask for a written final position. Keep the policy wording, claim form, denial letter, medical records, receipts, and notes of every conversation.

If the matter remains unresolved, the Financial Consumer Agency of Canada points consumers with life or health insurance complaints to the OmbudService for Life and Health Insurance. You can also contact your provincial or territorial insurance regulator. Quebec residents may have a different route through the Autorité des marchés financiers.

For a Canadian public-health decision, contact the relevant provincial or territorial health ministry or plan administrator. Do not use the U.S. 180-day, 60-day, or 72-hour deadlines unless your own Canadian plan documents specifically provide them.

Common mistakes that can weaken an appeal

• Missing the deadline while waiting for the provider to correct the claim
• Sending original medical records instead of copies
• Arguing that a treatment is necessary without addressing the denial reason
• Failing to ask the doctor for a focused letter of medical necessity
• Assuming a phone call counts as a formal appeal when the plan requires writing
• Ignoring a separate prior-authorization or network dispute
• Continuing to receive non-emergency care without asking how payment will be handled

Your safest next step is to read the denial notice today, mark the earliest deadline on your calendar, request the relevant claim records, and submit a complete appeal through the official method listed by your plan.

Helpful Links

• HealthCare.gov: How to appeal an insurance company decision – Review the U.S. internal appeal and external review process for a denied health insurance claim.
• HealthCare.gov: Internal appeals – See what to include in an internal appeal and how insurers handle the review.
• HealthCare.gov: External review – Check when an independent external review may be available after a denial.
• CMS: Appealing health plan decisions – Review federal appeal rights, urgent cases, review timelines, and consumer assistance options.
• U.S. Department of Labor: Filing a claim for health benefits – Learn about employer-sponsored plan appeals, relevant records, deadlines, and external review.
• Canada.ca: How to file a complaint with your insurance company – Find the Canadian complaint process and escalation options for private health insurance disputes.
• Appealing an insurance company decision – Official page referenced in the article.

Frequently Asked Questions

Q. Can I appeal a denied claim if I already paid the medical bill?

A. Usually, yes. A claim can often be appealed whether you paid the provider, received a bill, or are still waiting for the insurer to process payment. Include proof of payment and ask how any reimbursement will be handled if the claim is overturned.

Q. What if the insurer says the treatment was not medically necessary?

A. Ask your doctor for a detailed letter explaining your diagnosis, the treatment requested, prior treatments tried, expected benefit, and why the insurer’s alternative would not be appropriate. This type of denial may qualify for external review after the internal appeal.

Q. Can I appeal a denial by phone?

A. For a standard appeal, follow the written instructions in your denial notice. In an urgent situation, federal rules may allow a verbal expedited appeal, but ask the plan how to document the request and obtain written confirmation.

Q. What if my health plan does not respond by the deadline?

A. Keep proof of when the appeal was received and contact the plan promptly. Ask whether the appeal is overdue and whether you can request external review or assistance from your state insurance department, Consumer Assistance Program, or the U.S. Department of Labor for an employer plan.