An excess charge is what a provider may bill above the Medicare-approved amount when they have not agreed to accept that amount as full payment. It is a narrow rule, it is capped, several states have legislated it away, and it is worth understanding mainly because it is the one line where two standardised Medigap letters genuinely differ in a way a reader can act on.
Where the charge comes from
Providers who accept assignment agree to take the Medicare-approved amount as full payment. Providers who do not may bill above it, within a limit set in federal rules, and that excess is billed to the patient. Most care is delivered by providers who accept assignment, which is why many people never encounter this at all, and why the exposure depends heavily on who a particular person actually sees rather than on any national figure.
Which Medigap letters cover it
The standardised benefit chart is explicit about this line: some letters cover Part B excess charges and others do not, and it is one of the clearest differences between Plan G and Plan N. Because the letters are standardised in federal law, that difference is identical whoever issues the policy, which makes it one of the few Medigap comparisons a reader can make without a quote. The chart is linked below and is the authority.
Several states have removed the question
A number of states restrict or prohibit excess billing outright, which means the line on the Medigap chart matters much less to residents there than to residents elsewhere. It is therefore a genuinely state-dependent consideration, in a market where most considerations are federal, and the place to confirm it is a state insurance department or the free counselling service. This site publishes the state enrollment picture; it does not hold each state's billing rules.
Questions people ask about what are part b excess charges
Is there a limit on an excess charge?
Yes, federal rules cap how far above the Medicare-approved amount a non-participating provider may bill.
Does Original Medicare pay excess charges?
No. They fall to the patient unless a supplement policy covering that line pays them.
How do I avoid them?
By using providers who accept assignment. Medicare's own directory shows which providers do.
Do they exist in every state?
No. Several states restrict or prohibit the practice, which makes the question much less important there.