Medical bills often contain errors — and you are responsible for catching them
Medical billing errors happen frequently enough that hospitals and insurers have formal dispute processes for them. The most common mistakes are duplicate charges (the same service billed twice), incorrect quantity (you were charged for five injections when you received one), wrong procedure codes that inflate the bill, and charges for services you never received. These errors can add hundreds or thousands of dollars to your bill.
You have the right to dispute any charge you believe is wrong. The process differs slightly depending on whether your insurer has already paid part of the bill, but in both cases you start by requesting an itemized bill and comparing it to what actually happened during your visit. Most disputes are resolved within 30 to 60 days if you provide clear documentation.
Key Takeaways
- Request an itemized bill when ready after your visit — the summary bill hospitals send first hides the individual charges where errors hide.
- Compare the itemized bill line by line to your visit notes, receipts, and explanation of benefits to spot duplicate charges, wrong quantities, or services you did not receive.
- Submit your dispute in writing to both the hospital billing department and your insurance company (if applicable), with copies of the evidence supporting your claim.
- If the hospital or insurer denies your dispute, you can file a complaint with your state's insurance commissioner or attorney general's office at no cost.
How to request and read an itemized bill
The bill you receive in the mail is usually a summary that groups charges by category — "Hospital Services," "Lab Work," "Pharmacy" — without showing what each individual item cost. This summary hides errors. You need the itemized bill, which lists every single charge with its procedure code, description, quantity, and price.
Call the hospital's billing department and ask for an itemized bill in writing. You can also request it by mail or through the hospital's patient portal if one exists. By law, hospitals must provide this within 30 days. Ask them to send it to your home address, not just make it available online, so you have a dated copy for your records.
When the itemized bill arrives, read it line by line. Look for the procedure code (a five-digit number starting with 9 or a four-letter code starting with C), the description of what was done, the quantity, and the charge. Cross-reference each line against your visit summary, any paperwork you received during your visit, and your insurance company's explanation of benefits if you have one.
Common billing errors and how to spot them
Duplicate charges are the most frequent error. You will see the same procedure code and description listed twice, sometimes on the same day. This happens when a charge is entered into the billing system twice by mistake, or when a charge meant to be reversed is not. Compare dates and procedure codes carefully — if you see the exact same charge within a day or two, it is likely a duplicate.
Incorrect quantity means you were charged for more units of a service than you received. For example, you might be charged for five doses of a medication when you received one, or for three physical therapy sessions when you attended one. Check your visit notes or any receipts you were given during your appointment. If the quantity on the bill does not match what you remember, note the discrepancy.
Wrong procedure codes are harder to spot without medical knowledge, but they matter because different codes have different prices. A code for a basic office visit costs less than a code for a complex evaluation. If you received a straightforward visit but the bill shows a code for a lengthy consultation, the code may be wrong. You can search procedure codes on the CMS (Centers for Medicare and Medicaid Services) website to see what each code is supposed to cover.
Charges for services not rendered appear on bills when a service is coded and billed but never actually performed. This might be a lab test that was ordered but cancelled, or a procedure that was planned but did not happen. Check your visit notes and ask the provider directly if you are unsure whether a service took place.
How to dispute a charge with the hospital
Write a letter to the hospital's billing department. Include your name, date of birth, account number, and the date of service. Describe which charge you are disputing, why you believe it is wrong, and what evidence supports your claim. Attach copies (not originals) of the itemized bill with the disputed charge highlighted, your visit notes, any receipts, and any other documentation.
Send the letter by certified mail with return receipt requested, so you have proof the hospital received it. Keep a copy for your records. The hospital must respond within 30 days. If they agree the charge is wrong, they will issue a credit to your account. If they disagree, they must explain their reasoning in writing.
Do not pay the disputed charge while the dispute is pending. If the hospital sends the bill to a collection agency, send the collection agency a copy of your dispute letter and ask them to pause collection efforts until the dispute is resolved. Under federal law, collection agencies must stop collection activity for 30 days while a dispute is being investigated.
How to dispute a charge with your insurance company
If your insurance company has already paid the hospital and you believe the charge should not have been paid, contact your insurer's customer service line. Explain which charge you are disputing and why. Ask them to review the claim and determine whether it should have been paid.
Insurance companies have their own dispute process, separate from the hospital's. Your insurer may contact the hospital directly to investigate. This process typically takes 30 to 60 days. Your insurer will send you a written decision explaining whether they agree the charge was incorrect and, if so, whether they will recover the money from the hospital or adjust your account.
If your insurer denies your dispute, ask them in writing to explain their decision and cite the specific policy language or medical reason for the denial. Request the name and contact information of the person who made the decision. Keep this documentation — you will need it if you file a complaint with your state's insurance commissioner.
What to do if the hospital or insurer refuses to correct the error
If the hospital or insurer denies your dispute and you still believe the charge is wrong, file a complaint with your state's insurance commissioner. This office oversees insurance companies and investigates complaints about claim denials and billing disputes. The complaint is free to file and does not require a lawyer.
To find your state insurance commissioner, search "[your state] insurance commissioner" online. Most states allow you to file a complaint through their website or by mail. Include copies of your itemized bill, your dispute letter, the hospital's or insurer's response, and any other supporting documentation. The commissioner's office will investigate and contact the hospital or insurer on your behalf.
If the error involves a charge for a service you never received or a duplicate charge, you can also file a complaint with your state's attorney general's office. Some states have consumer protection divisions that handle healthcare billing complaints. This is also free and does not require a lawyer.
How billing errors affect your credit and what to do about them
If a disputed charge goes unpaid long enough, the hospital may send it to a collection agency. Once a debt is in collections, it can damage your credit score. However, you have protections: if you have submitted a written dispute to the hospital or your insurer, collection agencies must pause collection efforts for 30 days while the dispute is being investigated.
If a disputed charge appears on your credit report, you can dispute it directly with the credit reporting agency. Write to Equifax, Experian, or TransUnion (or all three) and explain that the charge is disputed. Include a copy of your dispute letter to the hospital or insurer. The credit agency must investigate within 30 days and remove the item if it cannot be verified.
Keep records of every step: your dispute letters, the hospital's responses, your credit report, and any correspondence with collection agencies or credit bureaus. These documents protect you if the dispute takes months to resolve.
Frequently Asked Questions
How long do I have to dispute a medical bill?
There is no federal time limit, but most hospitals and insurers expect disputes within 90 days of receiving the bill. The sooner you dispute, the easier it is to investigate — records are fresher and staff remember the visit. If you discover an error months later, submit your dispute anyway; hospitals often honor them even if they are late.
Can I dispute a bill my insurance company already paid?
Yes. You can dispute the charge with your insurer, and they can investigate whether the hospital overbilled or billed incorrectly. If your insurer agrees, they may recover the overpayment from the hospital or adjust your account. You can also dispute the charge directly with the hospital even if insurance paid part of it.
What if the hospital says the charge is correct but I still disagree?
Request a detailed explanation of why the charge is correct, including the medical reason for the service and the procedure code used. If you still disagree, file a complaint with your state's insurance commissioner or attorney general. You can also ask the hospital for an independent review by their patient advocate or ombudsman.
Do I need a lawyer to dispute a medical bill?
No. You can dispute a bill on your own by writing a letter and submitting documentation. If the dispute involves a large amount or the hospital refuses to respond, you may want to consult a lawyer, but most disputes are resolved without legal help.
What happens if I ignore a medical bill I think is wrong?
If you do not pay or dispute it, the hospital will eventually send it to a collection agency. This damages your credit score and the collection agency can sue you for the amount owed. Always dispute in writing if you believe a charge is incorrect — disputing protects you legally and stops collection efforts while the dispute is being investigated.