How to Read Your First Medicare Bills and Plan Notices

Not every bill means something is wrong, but every bill should be understood before ignored.

In your first year with Medicare, you will receive several different kinds of documents that look like bills but are not all bills. The Medicare Summary Notice is a summary, not a bill. The Explanation of Benefits from a Medicare Advantage or Part D plan is also a summary. Actual bills come from Medicare (for Part B premium, if not deducted from Social Security), from your plan (for plan premiums), and from providers (for amounts you owe after coverage paid). The safest move is to match every bill or notice to its source before paying or ignoring it.

Short answer: Medicare documents come in three categories — summaries (informational), plan statements (informational), and actual bills (require action). Confusing the three is the most common cause of paying something you do not owe, or ignoring something you do.

How this applies to you

If a document arrived and you are not sure what it is. Look for the words “This is not a bill” near the top. The Medicare Summary Notice and the Explanation of Benefits both say this prominently. If you see those words, you are reading a summary, not a bill.

If you got a bill you did not expect. Do not pay it until you know what it is. Match the bill to a service you received, to a plan you are enrolled in, or to a premium you owe. If you cannot match it, call the source before paying.

If you received nothing and you are wondering whether you should have. Your Medicare.gov account and your plan’s online account both show what was processed. Logging in is usually faster than waiting for paper mail.

If you are helping a parent. Mail piles up. Sort it into three piles: summaries (file in the year folder), plan statements (file in the year folder, but read first), and bills (open immediately, verify, then either pay or call).

The documents you will see

Medicare Summary Notice (MSN)

Sent by: Medicare Frequency: Every three months if you have Original Medicare and had any Medicare-covered services in that quarter. You also can view it any time at your Medicare.gov account. What it shows: Services provided, what Medicare paid, what was applied to your deductible, what you may owe the provider. Action required: None — this is a summary. Read it. Match each line to a visit or service. File it. Call the provider only if something looks wrong.

Common confusion: The MSN shows “Maximum you may be billed.” That is not a bill. It is the upper bound of what the provider can charge you. The actual bill (if any) comes from the provider, not from Medicare.

Explanation of Benefits (EOB) — from a plan

Sent by: Your Medicare Advantage plan or Part D plan Frequency: Monthly, in any month you had a service or filled a prescription. Also available in your plan’s online account. What it shows: Services or prescriptions, what the plan paid, what counted toward your deductible or out-of-pocket maximum, what you owe. Action required: None — this is also a summary. Read it. File it. Call the plan only if something looks wrong.

Common confusion: The EOB can show an amount under “Member responsibility” or “What you owe.” If you already paid that amount at the visit or pharmacy, you do not owe it again. The EOB is reflecting what happened, not asking for payment.

Provider bill

Sent by: The doctor’s office, hospital, or other provider Frequency: After a visit, usually within thirty to sixty days What it shows: Services, what insurance paid, what you owe Action required: This is an actual bill. Before paying:

• Match it to a service you received
• Compare the amount you owe against the MSN or EOB
• If the amount is more than the MSN or EOB shows, call the provider’s billing office and ask them to verify

If the bill matches the MSN or EOB, pay it according to the provider’s instructions. Save the payment confirmation.

Premium bill — Part B

Sent by: Medicare Frequency: Quarterly (every three months) if your Part B premium is not deducted from your Social Security benefit. Monthly if you set up automatic withdrawal. Action required: Pay by the due date listed on the bill. Late payment can lead to coverage termination. If you are not yet taking Social Security, this bill is real and important.

If you are taking Social Security, your Part B premium is deducted from your monthly benefit. You should not receive a separate Part B premium bill in that case. If one arrives, call Social Security to verify before paying.

Premium bill — Medicare Advantage, Part D, or Medigap

Sent by: Your plan or the Medigap insurer Frequency: Monthly Action required: Pay by the due date. Many people set up automatic bank withdrawal once they confirm the plan and amount are correct.

Annual Notice of Change (ANOC)

Sent by: Your Medicare Advantage or Part D plan, every fall (typically by the end of September) What it shows: Changes the plan is making for the upcoming year — premium, copays, formulary, network, benefits Action required: Read it carefully. If the changes affect your medications, your doctors, or your costs, evaluate during Medicare Open Enrollment (October 15 through December 7). Many of the most consequential plan changes are first announced in the ANOC.

Evidence of Coverage (EOC)

Sent by: Your plan, usually in late fall along with the ANOC What it shows: The full rule book for the upcoming year — what the plan covers, what it does not, how appeals work, prior authorization rules, network details Action required: Keep it. You do not need to read it cover to cover, but you want it on hand when a specific question comes up.

Creditable coverage notices

Sent by: Employer plans, retiree plans, and some other coverage sources, each fall What it shows: Whether the drug coverage you have through that source is at least as good as standard Medicare Part D coverage Action required: Save it. If you ever need to enroll in Part D later, the creditable coverage notice can protect you from the late enrollment penalty. See Costs, Prescriptions & Part D for the broader Part D timing picture.

The match-before-act rule

When any document arrives:

• Identify what kind of document it is (summary, plan statement, provider bill, premium bill, ANOC, EOC, notice)
• Match the dates and amounts against what you know — visits, prescriptions, premium expectations
• If everything matches, file or pay as appropriate
• If something does not match, call the source before paying or ignoring

The two failure modes — paying what you do not owe, and ignoring what you do — both come from skipping the match step.

What people get wrong about Medicare paperwork

The most common mistake is treating every document like a bill. The Medicare Summary Notice and the Explanation of Benefits look like bills. They are not. Reading “what you may owe” as “what you must pay now” leads to double-paying or panic.

The second most common mistake is the opposite — treating real bills as junk mail. The Part B premium bill, the plan premium bill, and the provider bill all require action. Missing a Part B premium payment can lead to Part B coverage being dropped.

A short script for calling about a bill or notice

“Hello, I received a [bill / notice / statement] dated [date] for [amount]. I want to verify this is correct before I pay. Can you walk me through what this is for, what insurance has paid, and what I owe?”

Write down the answers. Get a reference number for the call. If anything is still unclear, ask for the explanation in writing.