The Excess Charge Explained

A Medicare Part B excess charge is an amount your doctor can bill you above what Medicare pays for the same service. It is not a copay or deductible — it is extra money on top of what Medicare has already decided the service is worth.

Here is how it works: Medicare sets a fee for each service (like an office visit or lab test). Your doctor can choose to accept that fee as full payment, or can bill you for the difference between what Medicare pays and what they actually charge. That difference is the excess charge. Not all doctors do this, and the amount varies widely by provider and location.

The excess charge can be 15 percent above the Medicare-approved amount in most cases, though some doctors charge more. If Medicare approves $100 for a service and your doctor's actual fee is $120, you could owe the $20 difference after Medicare pays its share.

Key Takeaways

  • Excess charges are amounts doctors bill above the Medicare-approved fee, and they are legal only if your doctor does not accept Medicare assignment.
  • A doctor who accepts assignment agrees to take Medicare's payment as full payment and cannot bill you the difference.
  • You can call your doctor's office before your visit to ask whether they accept assignment and what your out-of-pocket cost will be.
  • Some states limit excess charges to 10 percent or less, so your state of residence affects how much a doctor can charge you.
  • Medigap insurance (supplemental coverage) often covers excess charges, which is one reason people buy it alongside Part B.

Assignment and Non-Assignment: The Key Difference

Whether your doctor can charge you an excess charge depends on whether they accept assignment. A doctor who accepts assignment agrees to take Medicare's approved amount as full payment for the service. They bill Medicare, Medicare pays them, and you pay only your copay or coinsurance — nothing more.

A doctor who does not accept assignment can bill you for the difference between Medicare's approved amount and their actual fee. This is where the excess charge comes in. The doctor still must bill Medicare, but they can then send you a bill for the remainder.

You can find out whether a specific doctor accepts assignment by calling their office directly or by searching the Medicare provider directory on Medicare.gov. The directory shows assignment status for each doctor and their specialty.

State Limits on Excess Charges

Some states have passed laws that cap how much doctors can charge as an excess charge, even if they do not accept assignment. These limits vary by state and are usually 10 percent or less above the Medicare-approved amount.

Connecticut, Florida, Massachusetts, New York, Ohio, Pennsylvania, and Texas all have limits on excess charges. If you live in one of these states, your doctor cannot charge more than the state limit, regardless of what their actual fee is. Other states have no limit, which means a non-participating doctor can charge significantly more.

Check your state's insurance commissioner's office or your state's Medicare advocacy organization to learn what limit applies where you live. This information can save you hundreds of dollars on a single procedure.

How Medigap Coverage Affects Excess Charges

Many Medigap plans (supplemental insurance policies sold by private insurers) cover excess charges. Plans C, D, F, G, M, and N all include some level of excess charge coverage. Plan F and Plan G cover 100 percent of excess charges, meaning you pay nothing beyond what Medicare and your Medigap plan cover together.

If you have Medigap coverage, you should check your policy documents to see whether excess charges are included and at what percentage. Some plans cover them fully; others cover a portion. This is one of the main reasons people buy Medigap alongside Part B — it protects them from surprise bills.

If you do not have Medigap and your doctor does not accept assignment, you will owe the excess charge out of pocket. This is why knowing your doctor's assignment status before your visit matters.

What to Do Before Your Visit

Before you see a doctor, call their office and ask three things: Do they accept Medicare assignment? If not, what is their fee for the service you need? And what will your out-of-pocket cost be after Medicare pays?

Write down the answers. If the office cannot tell you the exact amount, ask them to estimate based on the service code. If the cost seems high and the doctor does not accept assignment, you have the option to seek care from a doctor who does accept assignment, or to ask whether the doctor will make an exception for you.

If you have Medigap, tell the office you have supplemental coverage and ask whether they bill it directly or whether you will need to submit the claim yourself. This affects how much you pay at the visit.

Excess Charges vs. Balance Billing

Excess charges and balance billing are related but not identical. An excess charge is specifically the amount a non-participating doctor bills above the Medicare-approved fee. Balance billing is a broader term that includes any bill for the difference between what a provider charges and what insurance pays.

In Medicare, balance billing by non-participating doctors is legal up to the excess charge limit. Balance billing by participating doctors (those who accept assignment) is illegal — they cannot bill you for the difference. If a participating doctor sends you a balance bill, you can report them to Medicare.

Understanding this distinction matters because it tells you whether a bill you received is legal or whether you have grounds to dispute it.

Finding Doctors Who Accept Assignment

The easiest way to avoid excess charges altogether is to see doctors who accept Medicare assignment. You can search for them on Medicare.gov by using the "Find Care Providers" tool. Enter your location and specialty, and the results will show you which doctors accept assignment.

You can also call your doctor's office directly and ask. Many primary care doctors accept assignment because it simplifies billing and keeps patients coming back. Specialists are more likely to have mixed practices — some accepting assignment, others not.

If your preferred doctor does not accept assignment, ask whether they will for your specific visit. Some doctors accept assignment for certain patients or certain services, even if they do not do so across the board.

Frequently Asked Questions

Can a doctor who accepts assignment ever charge me an excess charge?

No. A doctor who accepts assignment agrees to take Medicare's approved amount as full payment. They cannot bill you for the difference between their fee and Medicare's payment. If they do, that is illegal balance billing and you can report it to Medicare.

What if I receive an excess charge bill and I think it is wrong?

First, check whether your doctor accepts assignment. If they do, the bill is illegal and you should contact Medicare at 1-800-MEDICARE. If they do not accept assignment, check whether your state has an excess charge limit and whether the bill exceeds it. If it does, contact your state insurance commissioner's office.

Does Medicare Part B cover the excess charge?

No. Medicare pays only up to the approved amount. The excess charge is your responsibility unless you have Medigap or other supplemental coverage that covers it. This is why some people buy Medigap specifically for excess charge protection.

If I have a Medigap plan, do I still owe the excess charge?

It depends on your plan. Plans F and G cover excess charges at 100 percent. Other plans cover them partially or not at all. Check your policy documents or call your Medigap insurer to confirm what your plan covers.

Can I negotiate an excess charge with my doctor?

You can ask, especially if you are paying out of pocket. Some doctors will reduce or waive the excess charge if you explain financial hardship. There is no harm in asking before the service is provided, but you have no legal right to the reduction unless your state law requires it.