By Christian BrinkleyLicensed NC Insurance Agent, NPN 22217190, NC Life & Health · Updated October 14, 2026 · 4 min read
You got a bill from a doctor that was higher than what Medicare approved. You paid your normal coinsurance. Then there was an extra charge on top. That extra charge might be a Part B excess charge. Excess charges are one of the most confusing parts of Original Medicare. They only show up in one specific situation. Once you understand that situation, you can mostly avoid them.
What Excess Charges Actually Are
Medicare sets an approved amount for every covered service. Think of it as the price Medicare thinks the service is worth. Normally, you pay 20 percent of that approved amount as coinsurance, and Medicare pays the other 80 percent. That is the standard split for Part B services after you meet your deductible.
An excess charge happens when a provider bills you more than the Medicare approved amount. Not all providers can do this. Only non-participating providers can charge excess charges. Participating providers cannot. We will get to that distinction in a minute.
The 15 Percent Limit
The 15 percent limiting charge is set by federal law. It applies everywhere in the country. A provider cannot waive it, negotiate past it, or ignore it. They can charge less than the limit if they want. Many do not.
It helps to know the math. If the approved amount is 200 dollars, the most the provider can bill is 230 dollars. Your coinsurance is still based on the approved amount, so you would owe 40 dollars in coinsurance plus up to 30 dollars in excess charges.
Participating vs Non-Participating vs Opt-Out Providers
This is where it gets practical. Every doctor who works with Medicare falls into one of three groups.
Participating providers agree to accept Medicare's approved amount as payment in full. They accept assignment. You pay your 20 percent coinsurance and your deductible share. No excess charges, ever. This is the group you want.
How to Avoid Excess Charges
The easiest way to avoid excess charges is to use participating providers. Most doctors are participating. Medicare's provider finder on medicare.gov lets you filter for providers who accept assignment.
If you see a non-participating specialist because they are the best option for your condition, ask up front whether they will accept assignment for your visit. Some non-participating providers accept assignment on a case by case basis. Asking costs you nothing.
What to Do If You Get Billed Too Much
First, check the bill against your Medicare Summary Notice. The Summary Notice shows the approved amount and what you owe. If the bill is more than the approved amount plus the allowed excess, something is wrong.
Second, call the provider's billing office. Mistakes happen. A charge above the 15 percent limit is often a billing error. Ask them to recheck the limiting charge calculation.
Third, you can file a complaint with Medicare. If a non-participating provider charges more than the limiting charge, that is a violation. Medicare takes these complaints seriously.
The Bottom Line
Excess charges are the extra up to 15 percent that non-participating providers can bill above Medicare's approved amount. Participating providers never charge them. The fix is almost always the same: confirm the provider accepts assignment before the visit, and keep your Medigap plan letter in mind if you have one.
This article is for general information only and is not legal, tax, or insurance advice. Medicare rules change and vary by state. For free, unbiased help, contact your State Health Insurance Assistance Program (SHIP), call 1-800-MEDICARE, or talk with a local licensed insurance agent who can review your specific situation.
Questions people ask me about this
What excess charges actually are?
Medicare sets an approved amount for every covered service. Think of it as the price Medicare thinks the service is worth. Normally, you pay 20 percent of that approved amount as coinsurance, and Medicare pays the other 80 percent. That is the standard split for Part B services after you meet your deductible.
What is the 15 percent limit?
The 15 percent limiting charge is set by federal law. It applies everywhere in the country. A provider cannot waive it, negotiate past it, or ignore it. They can charge less than the limit if they want. Many do not. It helps to know the math. If the approved amount is 200 dollars, the most the provider can bill is 230 dollars.
How do I avoid excess charges?
The easiest way to avoid excess charges is to use participating providers. Most doctors are participating. Medicare's provider finder on medicare.gov lets you filter for providers who accept assignment.
What to do if you get billed too much?
First, check the bill against your Medicare Summary Notice. The Summary Notice shows the approved amount and what you owe. If the bill is more than the approved amount plus the allowed excess, something is wrong. Second, call the provider's billing office. Mistakes happen. A charge above the 15 percent limit is often a billing error.
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