📬 Your Medicare ANOC Letter, Explained in Plain English

By Muhammad Imran · Reviewed for accuracy against CMS and Medicare guidance · Last updated October 2026.

It arrives in a plain envelope, usually in late September. Thick. Fine print. A chart comparing "2026" and "2027" columns that makes your eyes glaze over by row three. Most people set it on the kitchen table meaning to read it later. And later never comes.

Here is the problem: that letter is the single most important piece of mail your health plan sends you all year. It tells you, in advance, exactly how your coverage and costs change on January 1. Your premium. Your deductible. Whether your prescriptions are still covered. Whether your doctor is still in the network. Ignore it, and you can walk into January paying hundreds of dollars more. Or discovering at the pharmacy counter that your medication is no longer covered.

You are not alone in finding it confusing. In an eHealth survey of more than 500 Medicare beneficiaries, only 36% said their Annual Notice of Change letter was "readily understandable". And barely half (48%) said they read their insurer's mail carefully at all. This guide translates the whole thing into plain English: what the letter is, the six sections that actually matter, the dates you cannot miss, where to get free help, and how to tell the real letter from the Medicare scam calls that swarm this season.

What the ANOC is (and who gets one)

Per Medicare's own definition, your plan sends you a Plan Annual Notice of Change each fall, and it includes any changes in coverage, costs, and more that take effect in January. Medicare's instruction is simple: review it to decide whether your plan will still meet your needs next year.

Who receives one:

• Medicare Advantage (Part C) members. Yes, you get one every year.
• Stand-alone Part D prescription drug plan members. Yes, from your drug plan.
• Original Medicare only (Parts A and B). No. Original Medicare is a standardized government program; its costs don't change plan-by-plan, so there is nothing to announce.
• Medigap policyholders. No ANOC (Medigap plans are standardized), though your Medigap premium itself can still change.

One more thing people get wrong: the letter comes from your plan, not from Medicare. It arrives by mail (or in your plan's secure member portal). Never by a phone call, text, or email asking you to "verify" anything. Keep that fact handy; it is the backbone of the scam section below.

When it arrives. And what to do if it doesn't

Federal rules require your plan to get the ANOC into your hands by September 30 each year. Timed so it lands about two weeks before open enrollment opens on October 15. A companion document, the Evidence of Coverage, must reach you by October 15.

If October arrives and you never got yours:

1. Call your plan's member services number. It is printed on your insurance card. Ask them to send another copy.
2. Check your online member portal. Most plans post the ANOC there as a PDF.
3. Do not trust a caller who offers to help. No legitimate plan "resends" your ANOC by reading it to you over the phone or emailing it to an address you did not provide. That is a scammer fishing for your information.

The six sections that actually matter

You do not need to read the whole letter word for word. Every ANOC follows the same federally required outline, so hunt for these six sections. They are where the money is:

1. Your monthly premium

What you pay each month for the plan itself. Even a $15 increase adds up to $180 over the year. If the premium jumped, that alone can justify shopping around.

Part of that premium can also be income-based, so check your IRMAA to see the income-based part of what you pay.

2. Your yearly deductible

What you pay out of pocket before the plan starts paying. Deductibles reset every January 1, and plans change them quietly. A deductible that doubled can dwarf a premium increase.

3. Your prescription drugs (the formulary)

This is the section that blindsides people. Plans can remove drugs from their covered list or move them to a higher-priced tier each year. If your medication moved from Tier 1 to Tier 3, your copay could triple overnight. Check every drug you take by name. (Plans must also warn you in writing at least 60 days before any mid-year formulary change.)

4. Your doctors and hospital (the network)

Is your doctor still in the plan's network next year? Is your hospital? Going out-of-network. Even by accident. Can mean paying the full bill yourself. If your doctor left the network, that is a strong reason to switch plans.

5. Your extra benefits

Dental, vision, hearing, gym memberships, grocery allowances, over-the-counter credits. The extras Medicare Advantage plans advertise. These change more often than people expect. Verify each benefit you actually use.

6. Your maximum out-of-pocket limit (MOOP)

The most you could pay in a year for covered medical services. Think of it as your worst-case cap. If it rose from $4,000 to $7,000, your financial safety net got thinner. Worth knowing before January, not after a hospital stay.

ANOC vs. Evidence of Coverage. Don't confuse them

Along with the ANOC, your plan sends the Evidence of Coverage (EOC). The full contract, often around 200 pages, covering every benefit, cost, plan rule, and appeal right in exhaustive detail.

The practical rule: read the ANOC first. It is the "diff". This year versus next year, side by side. Open the EOC only when you need the fine print on something the ANOC says changed. Nobody expects you to read 200 pages; the ANOC exists precisely so you don't have to.

Key dates. Put these on the fridge

• By September 30: your ANOC must be in your hands.
• October 15 – December 7: Medicare open enrollment. This is your window to switch plans, and your request must reach the new plan by December 7.
• January 1: your new (or newly changed) coverage takes effect.
• January 1 – March 31: Medicare Advantage Open Enrollment Period. Only for people already in a Medicare Advantage plan. You can switch Advantage plans once, or return to Original Medicare.

The scam version: same season, fake letter

Open enrollment is also scammer season, and the ANOC gives criminals a perfect opening. Here is how to tell the real thing from the fake:

• The real ANOC comes by mail (or your plan's secure portal). It never arrives as a phone call, text, or email asking you to "verify" your Medicare number.
• Medicare will never call, text, or email you asking for your Medicare number or personal information. And never calls to enroll you in anything. If you didn't call them first, hang up.
• "Your plan is ending, I need to switch you today". A lie designed to harvest your Medicare number. Real plan changes happen only when you initiate them.
• "Your ANOC shows new free benefits. Just confirm your information". Free benefits never require handing your Medicare number to a stranger on the phone.

Victims often don't discover the fraud for weeks. Until the pharmacy says a prescription isn't covered, or the doctor's office says they're suddenly out of network. If a caller already got your Medicare number, call 1-800-MEDICARE (1-800-633-4227) right away, and report the fraud to the Senior Medicare Patrol at 1-877-808-2468.

For the full playbook of open-enrollment scams, see our guide: Medicare Open Enrollment Scams. 5 Red Flags.

What to do next. Four steps before December 7

1. Read the diff, not the whole letter. Go straight to the six sections above. Circle anything that changed. If nothing meaningful changed and you're happy, you're done. Doing nothing keeps your plan.
2. Compare on Medicare's official Plan Finder. At medicare.gov/plan-compare, enter your ZIP code, your drugs and doses, and your pharmacies. It estimates your total yearly cost under each available plan, cheapest first. Free, unbiased, and you can enroll right there.
3. Talk to a free SHIP counselor. Every state has SHIP (State Health Insurance Assistance Program) counselors. Free, local, unbiased Medicare help from people who sell nothing and earn no commissions. Find yours at shiphelp.org or call 1-877-839-2675.
4. Decide by December 7. Your enrollment request must reach the new plan by December 7 for January 1 coverage. Mark the date. After it passes, you're locked in (except during the January–March Advantage window).

Sources: Centers for Medicare & Medicaid Services. Medicare.gov; 42 CFR 422.2267(e)(3) and 423.2267(e)(3) (September 30 ANOC deadline); eHealth press release, August 1, 2024 (36% understandability survey of 500+ beneficiaries); State Health Insurance Assistance Programs (shiphelp.org). Last updated October 2026.