How to appeal a health insurance denial
On one income, a denied claim can feel like a wall. It is usually a door you have to knock on more than once.
This is part 2 of my medical bill guides. If you have not checked the bill itself yet, start with how to check a medical bill before you pay it.
Her book: What Your Doctor Wants You to Know to Crush Medical Debt (get the book) · Her website: CrushMedicalDebt.com
- Call and collect. Call your insurer, then gather the EOB, circle what was denied and get backup from your records and your doctor.
- Let your doctor's office appeal first. Their billers know each insurer's rules. If that fails, file your own appeal and have your doctor explain the reason again, in new words.
- Go outside the insurer. If the final answer is still no, ask for an independent external review. Your insurer must accept that decision.
First, find out why it was denied
The denial letter or EOB gives a reason. The reason tells you which fix to try first.
- A coding or billing mistake (wrong code, wrong date, typo in your ID): ask your doctor's or hospital's billing office to send a corrected claim. This often fixes it without a formal appeal.
- Missing information: send what the insurer asked for, and note the date you sent it.
- No prior authorization or prior authorization denied: ask your doctor's office to appeal, and ask whether your doctor can speak directly with the insurer's reviewer (often called a peer-to-peer review). If the care is urgent, ask for a fast appeal.
- Not medically necessary: this is where a letter from your doctor, your records and the reason in plain words matter most. See steps 3 and 4.
- Out of network: for emergency care, the No Surprises Act protects most insured people from out-of-network charges. Ask the insurer to reprocess the claim at the in-network rate.
- Not covered by your plan: read the plan document for the rule they cite, then appeal if you think it was applied wrongly. Ask whether the plan makes exceptions.
Step 1: Call your insurance company first
Call the member number on the back of your insurance card and explain the mistake you found. Some errors get fixed on that call. If the representative tells you the denied service can only be corrected through a formal appeal, write down their name and the date, and move to step 2.
Step 2: Gather your paperwork
- Get the Explanation of Benefits (EOB) and the denial letter. Find the service or item that was denied and the reason and plan rule the insurer gives.
- Circle each service you disagree with.
- Get backup: your medical records, the itemized bill and any note from your doctor. If your plan is through a job, the plan must give you free copies of the documents and records used to decide your claim. Ask for them in writing.
- Keep notes on every call: date, time, name and title of the person you spoke with.
- Keep your originals. Send copies.
Step 3: Ask your doctor's office to appeal for you
Your doctor wants the bill paid too. Call the office and ask for the office manager or biller. They can file a provider appeal, which is usually the first formal step. Every insurer has its own rules for appeals, and billers work with those rules every day, so they are often the best people to file it correctly. Ask your doctor to explain in writing why the care was needed.
Step 4: If it is denied again, file your own appeal
Many plans have two levels: the provider appeal, then a member appeal that you file yourself. Use your insurer's form if it has one. If not, a letter works.
- Put your name, claim number and insurance ID number at the top.
- Write a short summary of the denied service and say that you already asked once without success.
- Answer the reason in the denial letter directly, point by point.
- Most important: ask your doctor to explain the medical reason again, in different words. A new way of stating the case can make a big difference.
- Include a copy of the first appeal, any related records and any new evidence.
- Send it to the address in the decision letter or on the EOB, and keep a copy.
For job-based plans, a different person must review your appeal than the one who denied it, and the plan must decide within 30 days for care you have not had yet, 60 days for care you already had, and 72 hours if it is urgent.
Deadlines: Dr. Virgie recommends acting within about 2 months of the denial. For most plans, federal rules give you up to 180 days (6 months) to file an internal appeal. Your denial letter lists your plan's exact deadline, so check it.
Sample appeal letter
Copy this, fill in the brackets and keep it short. Attach your doctor's letter and the records that support it.
[Date] To: [Appeals department and address from the denial letter] Re: Appeal of claim denial Member name: [Your name] Member ID: [Insurance ID] Claim number: [Claim number] Date of service: [Date] Provider: [Doctor or hospital] I am appealing the denial of [service] dated [date of denial letter]. The reason given was [reason from the letter]. I disagree because [one or two plain sentences]. My doctor, [name], explains why this care was medically necessary in the attached letter. [If this is a second appeal: I asked once before on [date] without success.] Please send me copies of all documents, records and guidelines used to decide this claim. Attached: denial letter, EOB, doctor's letter, [records]. Sincerely, [Your name] [Phone] [Email]
If your insurance is through your job
Ask HR for help. Large employers that pay claims themselves (self-insured plans) often have a representative who works with the insurance plan on disputes. Ask HR for that person's contact information, then call and email them about your denial. The U.S. Department of Labor also answers questions about job-based plans at 1-866-444-3272.
Step 5: Ask for an external review
If the insurer still says no, you can ask an Independent Review Organization to decide. Under federal rules you generally have 4 months after the final denial to request an external review. A standard review is decided within 45 days, and an urgent one within 72 hours or less. Your insurer is required by law to accept the external reviewer's decision. The steps for your plan are in the final denial letter.
If the care is urgent, you can file the internal appeal and the external review request at the same time.
Which rules apply to you?
| Your coverage | First deadline | What to know |
|---|---|---|
| Job-based or Marketplace plan | At least 180 days from the denial | Internal appeal, then external review within 4 months of the final denial. |
| Original Medicare | The date printed on your Medicare Summary Notice | 5 levels of appeal. Circle the items on the notice or use form CMS-20027. Decision usually within 60 days. Medicare steps |
| Medicare Advantage | 65 days from the plan's denial | Ask for a fast appeal if waiting could harm your health (72 hours). If the plan says no, it goes to an independent reviewer automatically. Plan appeal steps |
| Medicaid or CHIP | The date in your notice | Call your state Medicaid agency. Your notice explains how to ask for a hearing. |
| No insurance or paying yourself | Within 120 days of the bill date | If the bill is $400 or more above your good faith estimate, you can dispute it with the federal government ($25 fee). |
Free help
- Your state's Consumer Assistance Program can help with, or even file, a health insurance appeal. Find yours at localhelp.healthcare.gov or call 1-800-318-2596.
- Job-based plans: U.S. Department of Labor benefits advisors, 1-866-444-3272.
- Surprise bills: the No Surprises Help Desk, 1-800-985-3059.
- A medical bill advocate can help with large or confusing denials. Dr. Virgie's CrushMedicalDebt.com has free resources and her book.
This page is general education, not legal, financial or medical advice. Rules differ by plan and state. In a medical emergency, call 911. Get care first and deal with the bill later.
Common questions
How long do I have to appeal a health insurance denial?
For most plans, federal rules give you up to 180 days (6 months) from the denial notice to file an internal appeal. Your denial letter lists your exact deadline, and acting sooner is better.
Can my doctor appeal an insurance denial for me?
Yes. Your doctor's office can usually file a provider appeal, and office billers know each insurer's requirements. Ask your doctor to explain in writing why the care was needed.
Why was my insurance claim denied?
The denial letter or Explanation of Benefits gives the reason. Common ones are a coding or billing mistake, missing information, no prior authorization, not medically necessary, out of network, or not covered by the plan. A coding mistake can often be fixed with a corrected claim from the doctor's office.
Can I get a copy of my insurance claim file?
If your plan is through a job, the plan must give you free copies of the documents and records used to decide your claim when you ask. Ask in writing.
What if my care is urgent?
Tell the insurer it is urgent and ask for a fast appeal. For most plans you can file the internal appeal and an external review request at the same time, and urgent appeals are decided within about 72 hours.
How do I appeal a Medicare denial?
For Original Medicare, file by the date on your Medicare Summary Notice by circling the items or using form CMS-20027. For a Medicare Advantage plan, ask the plan within 65 days of its denial.
What is an external review?
An independent review organization decides whether the insurer's denial stands. You generally have 4 months after the final denial to ask for one, and your insurer must accept the decision.
Written and medically reviewed by Harvey Castro, MD, MBA, board-certified emergency physician. Last reviewed October 25, 2026.