How to Read a Medicare Summary Notice and Catch Errors
The Medicare Summary Notice shows what Original Medicare paid and what you may owe. It isn't a bill. Here is what each section means and what to check.
If you have Original Medicare, you'll receive a Medicare Summary Notice (MSN), typically every few months when you've had services, or can view it online through your Medicare account. It lists services and supplies billed to Medicare, what Medicare approved and paid, and the maximum you may owe the provider.
It isn't a bill. Don't send payment to Medicare based on the MSN. Providers bill you separately.
If you're in a Medicare Advantage plan, you'll receive an Explanation of Benefits from your plan instead. Part D plans also send Explanations of Benefits.
Main sections
| Section | What it shows |
|---|---|
| Your account summary | Your deductible status and total you may be billed |
| Claims and services | Each service, provider, date, and amounts |
| Amount provider charged | What the provider billed |
| Medicare-approved amount | The amount Medicare allows for the service |
| Medicare paid | What Medicare paid the provider |
| Maximum you may be billed | Your share, such as deductible and coinsurance |
| Notes | Explanations, including denials |
| How to appeal | Steps and deadline to appeal a decision |
Worked example
A hypothetical outpatient visit where the Part B deductible has already been met:
If you have a Medigap policy, it may pay some or all of the $40. Providers who accept Medicare assignment generally can't bill you more than the Medicare-approved amount, which is why the $350 charge doesn't matter to you here.
What to check
- Services you received. Confirm each date, provider, and service. Unfamiliar charges can signal billing errors or fraud.
- Deductible status. Make sure deductible amounts are being tracked correctly.
- Denials. Read the notes for any service Medicare didn't pay, and why.
- Provider bills. Compare what your providers bill you with the "maximum you may be billed."
- Medigap crossover. If you have Medigap, check whether claims were automatically sent to it.
If something looks wrong
- Call the provider first about billing errors.
- Report suspected fraud to Medicare.
- Appeal a denial by following the instructions on the MSN before the deadline.
- Get help from your State Health Insurance Assistance Program (SHIP).
The takeaway
The Medicare Summary Notice is a record, not a bill. Checking it every time it arrives helps you catch errors, confirm what you owe, and spot fraud early.
Sources
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