How to Read Your Medicare Summary Notice — Teach enrollees how to spot billing errors and understand their EOB documents

The envelope from Medicare that shows up every few months might look like a bill, but it isn't. It's called a Medicare Summary Notice, and treating it like junk mail is one of the easiest ways to miss a costly error.

Original Medicare mails this notice at least twice a year for Part A and Part B services, listing every claim submitted on your behalf. Learning to read it takes just a few minutes once you know what to look for, and that small habit can protect both your wallet and your medical record.

Start with the basics.

The notice states clearly that it is not a bill. What it actually shows is what your provider billed, what Medicare approved, what Medicare paid, and the maximum amount you may still owe. It also tracks how much you have paid toward your annual Part B deductible, which is useful for budgeting the rest of the year.

Check the claims line by line.

For every service listed, confirm that the date, the provider name, and the description match a visit you actually remember. Errors are more common than most people realize. CMS reported that the Medicare improper payment rate reached roughly 6.55 percent in fiscal year 2025, amounting to close to $28.83 billion in improper payments.

Not every error is fraud. Many come from simple issues like a mistyped code, a duplicate charge, or a provider billing for a more complex visit than what actually took place, sometimes called upcoding.

Know what to do if something looks wrong.

Call the provider's billing office first. A wrong code or an honest clerical mistake can usually be corrected with one phone call and a resubmitted claim. If the explanation does not add up, or the provider cannot account for the service, contact 1-800-MEDICARE directly.

Keep notes on who you speak with and when, since this record can matter later.

Watch the deadline.

You can generally reference the notice to file an appeal within 120 days of receiving it if you disagree with a claims decision. Missing that window can turn a denied or incorrect charge into money you are responsible for paying. Setting a reminder to review each notice as soon as it arrives, rather than setting it aside, keeps that deadline from sneaking up on you.

Reviewing your Medicare Summary Notice regularly is one of the simplest ways to catch billing mistakes before they become a bigger financial or administrative headache. If you would like help understanding your coverage or reviewing recent notices, contact our office today.