80% of Medical Bills Contain Errors — Here's What to Look For
If someone told you there was an 80% chance your restaurant bill had the wrong total, you'd check it before paying. You'd count the items, verify the prices, and flag anything that didn't add up.
Medical bills deserve the same scrutiny. According to the Medical Billing Advocates of America, roughly 80% of medical bills contain errors. That's not a typo. Four out of five bills have something wrong — and those errors almost always favor the provider, not you.
The difference is that medical bills are designed to be confusing. They use codes you've never seen, jargon you don't understand, and formatting that makes it nearly impossible to know what you're actually being charged for.
That confusion is not accidental. It's profitable.
The Most Common Medical Billing Errors
Here's what to look for when you review your bill:
Duplicate Charges
The same service billed twice. This happens more often than you'd think, especially in hospital settings where multiple departments enter charges independently. If you see the same CPT code listed twice for the same date of service, that's a red flag.
Unbundling
Certain procedures are supposed to be billed as a package — one code, one price. Unbundling is when a provider splits that package into individual components and bills each one separately, resulting in a higher total. This is one of the most common and most expensive billing errors.
Upcoding
This is when a provider bills for a more expensive service than what you actually received. For example, billing a 45-minute office visit when your appointment lasted 15 minutes, or coding a routine check-up as a comprehensive evaluation.
Charges for Services Not Rendered
You'd be surprised how often this happens. A test that was ordered but never performed. A consultation that didn't take place. Supplies that were never used. If it's on the bill but didn't happen to you, it shouldn't be there.
Incorrect Patient Information
Wrong date of birth, wrong insurance ID, wrong name — even small data entry errors can cause claims to be denied, leaving you with a bill that should have been covered.
Balance Billing Violations
Under the No Surprises Act, you're protected from surprise bills for emergency services and certain out-of-network care at in-network facilities. If you're being balance-billed in a scenario covered by this law, that charge is illegal.
Incorrect Quantities
Billed for 10 physical therapy sessions when you attended 6. Charged for 3 units of medication when you received 1. Quantity errors are easy to miss but can add up to hundreds or thousands of dollars.
How to Catch These Errors
- Always request an itemized bill — not a summary, but a full line-by-line breakdown with CPT codes
- Compare against your EOB — your insurance company's Explanation of Benefits shows what was billed vs. what was covered
- Check dates of service — make sure every charge corresponds to a date you actually received care
- Look up CPT codes — a quick search can tell you what procedure a code represents and whether it matches what happened
- Verify quantities — count the units on every line item
- Cross-reference with your records — appointment confirmations, discharge papers, and prescriptions can all serve as evidence
What to Do When You Find an Error
Don't call. Write. Specifically:
- Draft a formal dispute letter identifying the specific errors
- Include copies of supporting documentation
- Send it via USPS certified mail with return receipt
- Keep copies of everything
A phone call can be denied, forgotten, or misrepresented. A certified letter creates a legal paper trail that demands a response.
Let BillFighter Find What You'd Miss
Going through a medical bill line by line is tedious. Catching unbundling violations and upcoding requires knowledge most people don't have. That's why we built BillFighter.
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