How to Dispute a Medical Bill
The bill says $1,840. Your Explanation of Benefits says your share should be $210. You know the number is wrong, but the hospital’s billing department is not budging. A formal dispute — with the right documentation and a written paper trail — is often the only thing that gets a billing error corrected.
Medical billing errors are not rare. Multiple studies and government audits have found that a substantial percentage of medical bills contain mistakes, from duplicate charges to services never rendered to outright fraud. If your bill does not look right, you have every right to question it — and a well-executed dispute can save you hundreds or thousands of dollars.
This guide walks you through the complete dispute process, from the first steps through escalating a case that is not being resolved.
Step 1: Get the Documents You Need
Before you can dispute anything, you need the paperwork.
Request an Itemized Bill
Call the provider’s billing department and ask for an itemized bill. This is a line-by-line breakdown of every service, supply, and charge. A regular statement that says “services rendered: $3,400” is not enough — you need to see exactly what you were charged for.
You have the right to an itemized bill. If the billing department resists, cite your state’s patient rights laws. Every state requires providers to provide itemized bills upon request.
Get Your Explanation of Benefits (EOB)
Contact your health insurance company or log into your member portal to download your EOB for the relevant claim. The EOB shows how your insurer processed the claim — what they were billed, what they paid, and what they say you owe, including the allowed amount and your patient responsibility. Use our EOB decoder to walk through it section by section.
Gather Your Medical Records
If you believe specific services were billed that were not provided, or that incorrect diagnosis codes were used, request your medical records for that visit or stay. You have a right to these records under HIPAA.
Step 2: Compare and Identify Errors
Lay your itemized bill and your EOB side by side. Compare them line by line:
- Does the EOB show the same services as the itemized bill?
- Does what you were billed match what your records show happened?
- Were there duplicate charges?
- Do the procedure (CPT) and diagnosis (ICD-10) codes match your actual treatment?
- Was your deductible or prior year credit applied correctly?
- Did your insurer process the claim at the in-network or out-of-network rate? Was that correct?
Make notes of every discrepancy. For a full list of what to look for, see our guide on common billing errors.
Step 3: Contact Your Provider’s Billing Department
Start here before escalating. Call the billing department and:
- Identify the specific charges you are questioning
- Ask them to explain what each charge represents
- Ask them to check for duplicate entries
- Request that any obvious errors be corrected
Keep a written record of every call: date, time, name of the person you spoke with, and what was said. If they agree to make a correction, ask for a confirmation in writing and a revised bill.
Step 4: Contact Your Insurance Company
If the problem involves how your insurer processed the claim — wrong network tier, missing discount, incorrect deductible application — call your insurer’s member services number.
Tell them:
- The claim number (from your EOB)
- What you believe is incorrect
- The specific line items in question
Your insurer may reprocess the claim, contact the provider, or initiate their own review. Ask for a case or reference number so you can follow up.
Step 5: File a Formal Written Dispute
If phone calls do not resolve the issue, escalate to a formal written dispute. Written disputes create a paper trail and trigger formal response timelines under your plan’s rules.
Your dispute letter should:
- Identify the date of service, claim number, and account number
- State the specific charges you are disputing
- Explain what you believe is incorrect and why
- Attach copies (not originals) of your itemized bill, EOB, and any supporting documentation
- Request a specific resolution (correction, refund, reprocessing)
- Note the deadline by which you expect a response
Use our dispute letter tool to generate a customized letter based on your situation. Send it via certified mail with return receipt, or through your insurer’s secure online portal with a confirmation of receipt.
Step 6: File a Complaint if Needed
If your dispute is not resolved satisfactorily, escalate:
For Insurance-Side Issues
- File a complaint with your state insurance department
- If your plan is an employer-sponsored ERISA plan, contact the U.S. Department of Labor’s Employee Benefits Security Administration (EBSA)
For Provider-Side Issues
- File a complaint with your state medical board or licensing authority
- Contact your state attorney general’s consumer protection office
For Surprise Bills
- Contact the federal No Surprises Act help desk at 1-800-985-3059 or cms.gov/nosurprises
For Medicare Patients
- Use the Medicare appeals process through your Medicare Advantage plan or Medicare Part B carrier
Step 7: Consider Professional Help
For large bills — particularly those involving hospitalizations or major procedures — a patient advocate or medical billing expert may be worth hiring. These professionals typically work on contingency (taking a percentage of what they save you) or for a flat fee. Organizations like the Patient Advocate Foundation and many hospital financial counseling departments can also help at no cost.
Key Timelines to Know
Do not delay starting this process. Important deadlines:
- Provider disputes: Many providers accept billing disputes within 60-120 days of the bill date
- Insurance appeals: Most plans require you to file an internal appeal within 180 days of receiving a denial notice
- External review: If your internal appeal is denied, you generally have 4 months to request an independent external review
- Timely filing: If a claim was not filed by the provider within your insurer’s timely filing window, it may have been denied. This is a provider error, and you should not be held responsible.
Get the Complete Dispute Kit for $19
Disputing a medical bill means writing letters, tracking deadlines, and knowing exactly what to say to billing departments and insurers. The $19 Complete Dispute Kit includes a customizable dispute letter, a billing error checklist, and a step-by-step guide for escalating unresolved disputes — everything in one download so you do not have to start from scratch. Get the Complete Dispute Kit
FAQ
Q: What if the provider sends my bill to collections while I am disputing it? A: Under the No Surprises Act and various state laws, providers generally should not report a disputed bill to collections. If this happens, send the collection agency and the provider a dispute letter immediately and note that the bill is under active dispute. Keep records of everything. You may also want to contact your state attorney general.
Q: Do I have to pay the bill while I dispute it? A: You are generally not required to pay a disputed amount while your dispute is under review, though policies vary. Ask your provider whether they will place the bill on hold during the dispute process and get that in writing.
Q: What if my insurer denies my appeal? A: If your insurer denies your internal appeal, you have the right to an independent external review by a third party not affiliated with your insurer. This is a powerful right — external reviewers overturn insurer decisions at meaningful rates.
Q: How long does a billing dispute take? A: Simple errors (like a duplicate charge) may be corrected in days. Formal appeals with insurers can take 30-60 days at the internal level. External reviews can take up to 60 days. Complex hospital billing disputes can take months.
Q: Can I dispute a bill that went to collections? A: Yes. You can dispute the underlying medical bill and the debt collection simultaneously. Send a debt validation letter to the collector and a separate dispute to the original provider. Under the Fair Debt Collection Practices Act, the collector must stop collection activity while they validate the debt.