What is the Medicare Annual Notice of Change letter for 2027?

It is the letter your Medicare Advantage or Part D plan must get into your hands by September 30, and it is the only document that tells you what your own plan is doing on January 1. Medicare describes it plainly: the Annual Notice of Change “includes any changes in coverage, costs, and more that will be effective in January.” The regulation behind it is more exact — a plan must send the notice for enrollee receipt no later than September 30 of each year.

From today that is 35 days. Then the Annual Enrollment Period opens on October 15 and closes December 7, which is the window in which anything you learn from the letter can actually be acted on.

I bring this up in August rather than October because of what the letter looks like when it lands. It is thick, it is beige, it arrives in the same week as three glossy mailers from plans you are not in, and it does not say “urgent” anywhere on it. In north Peoria I have watched more than one of these go into the recycling bin under a stack of advertising — and the mailer that survived was the one selling something. That is exactly backwards. The boring one is the only one written about the plan you already have.

What the Annual Notice of Change actually is

It is a standardized document. Federal rules classify the Annual Notice of Change as standardized marketing material, which means the plan has to use the form CMS gives it and can populate the variable fields but not rewrite the structure. That is why every one of these letters looks alike, and it is also why they are comparable — the version your neighbor in Vistancia gets from a different plan is laid out the same way as yours.

What it has to disclose is set by the rule requiring plans to notify enrollees of changes to plan rules that take effect on January 1. In practice that means the letter runs a side-by-side comparison of this year against next:

• Premium — the plan’s own monthly premium, which is separate from your Part B premium
• Deductibles — medical and drug, where the plan uses them
• Copays and coinsurance — office visits, specialists, urgent care, hospital stays, imaging, therapy
• Maximum out-of-pocket — the annual ceiling on what the plan can make you pay for in-network medical care
• The drug list — tier moves, drugs added, drugs dropped, new restrictions
• The pharmacy network — including which pharmacies count as preferred
• The provider network — whether the plan’s doctor and hospital network is changing
• Extra benefits — dental, vision, hearing, over-the-counter allowances, fitness, transportation

Two things are not in it, and both catch people out. It does not tell you whether your own specific doctor is still contracted next year — the letter speaks in terms of the network, not your chart. And it says nothing about IRMAA, the income-related surcharge on Part B and Part D, because that is Social Security’s determination rather than the plan’s. If you are subject to it, that arrives separately in its own letter later in the fall.

The four dates that box in this fall

Sources: Medicare.gov Open Enrollment page and the Code of Federal Regulations, Title 42. Federal deadlines — identical in Maricopa County and everywhere else.

Notice the shape of that calendar. You get the summary of what is changing two weeks before you are allowed to do anything about it, and the full contract on the same day the window opens. Those two weeks between September 30 and October 15 are the useful part of the fall, and they are the part most people spend not reading the letter.

How to read it in twenty minutes

You do not have to read the whole thing. Work in this order, because it is roughly the order in which these changes cost people money.

1. The drug list. If you take a maintenance medication, this is the first page that matters — earlier than the premium. A drug moving up a tier, or picking up a step-therapy or prior-authorization requirement, changes what you pay at the counter far more than a few dollars of premium does. Look for your own prescriptions by name, and look for the word “tier” next to each.

2. The maximum out-of-pocket. This is the number that decides what a bad year costs. A plan can hold its premium flat and raise this ceiling by a few thousand dollars, and the mailer will still say the premium did not change.

3. The provider network section. More on this below, because it is the one that bites here.

4. The copays you actually use. Not all of them — the four or five you incur in a normal year. A specialist copay going from one figure to another matters if you see a cardiologist quarterly and is noise if you do not.

5. The premium. Last, deliberately. It is the number everyone checks first and the one least likely to be the biggest change.

6. The extra benefits. Dental, vision, hearing and over-the-counter allowances are where plans trim quietly, because trimming them does not affect the headline. If you chose your plan partly for its dental allowance, check whether the allowance and the annual maximum are the same next year.

Keep the letter after you have read it. If something goes wrong in March, the Annual Notice of Change is your dated evidence of what the plan told you it would do.

The change that gets missed: the network

A provider network is renegotiated every year, and the contract between a plan and a medical group can end regardless of how long you have been a patient. The Annual Notice of Change will tell you the network is changing. It will not tell you that your cardiologist is on the wrong side of that change, because the letter is written to every member of the plan at once.

That is the gap you have to close yourself, and it means picking up the phone twice: once to the plan, and once to the practice. Ask the practice a specific question — not “do you take this plan?” but “are you contracted with this plan for next year, and has that been signed?” In August and September the honest answer is sometimes “we do not know yet,” which is itself useful information and a reason to check again in early October.

Separately, if a contracted provider is terminated, the plan has its own obligation to notify affected enrollees, with tighter requirements when the provider is a primary care or behavioral health provider. That notice comes when it comes, though — it is not something you can plan a year around. I wrote about the aftermath of exactly this in what happens if your doctor leaves your Medicare Advantage network, and how Advantage networks work is the longer explanation of why the contracts move at all.

Why this reads differently at the two ends of Peoria

Peoria runs close to thirty miles north to south, and the same letter does different damage at each end.

In 85383 — Vistancia, Trilogy, Blackstone, the Lake Pleasant Parkway and Happy Valley corridor — the households I sit with tend to have a primary care doctor near home and a specialist twenty minutes away in Arrowhead, or further south in Sun City where so much of the region’s Medicare-focused practice is concentrated. When your care is spread across a drive like that, the network paragraph in the letter is the paragraph that matters. A plan can keep its name, its premium and its benefit sheet completely unchanged while the group you drive to in Sun City goes out of network, and nothing about the front page of the letter will warn you.

The north end also has a lot of people who have been here two or three years and are still on a plan they first bought in another state, or one they picked on arrival without checking it against the specialists they now use. For them the Annual Notice of Change is worth reading as a prompt rather than a document — not “what changed?” so much as “does this still describe what I need?”

In 85345 and around Westbrook Village, the pattern is different. More households have used the same physician for fifteen or twenty years and the network question is narrower but sharper: one relationship, and whether it survives January. There is also a higher share of seasonal residents at that end and in the north’s active-adult communities alike — and if you are out of state four months a year, a network-based plan’s rules are a constraint you feel every year, not just when the letter arrives.

And then there is the seam. The Peoria–Glendale–Sun City ZIP boundaries are stitched tightly enough that neighbors a mile apart can be offered different plan line-ups, which is why comparing letters over the fence is a poor substitute for pricing your own ZIP. If your household sits near that line, the Peoria service-area page and the Glendale page both apply to you, and the answer follows the ZIP rather than the mailing address you think of as yours.

What the letter cannot change

Some of your costs are not the plan’s to move. Whatever the Annual Notice of Change says, Original Medicare’s own figures sit underneath every Advantage and Part D plan:

Higher-income households have a second letter to expect. IRMAA — the income-related surcharge added to Part B and Part D — starts above $109,000 for a single filer and $218,000 filing jointly, and for 2026 it is based on your 2024 return. The 2027 determination will use the return two years before that year, which is the one you filed this spring. Social Security makes that determination and mails it separately; your plan has nothing to do with it and will not mention it. If a one-off event pushed your income up — a property sale, a Roth conversion, the year you retired — Form SSA-44 is the route to have it reconsidered, and it is worth raising with your tax advisor at the same time you read this letter. You can see where your income lands in about a minute, and IRMAA explained covers the appeal in full.

If you are on Original Medicare with a supplement

You will not get an Annual Notice of Change for your supplement, because it does not work that way. Medigap benefits are standardised by federal law — a Plan G covers what a Plan G covers, year in and year out, and the letter you get from that carrier is a rate notice rather than a benefit change. What you will get an Annual Notice of Change for is your standalone Part D drug plan, and everything above about drug tiers and pharmacy networks applies to it in full.

That difference is the whole argument for supplements in the seasonal communities up here, and it is a real one: fewer moving parts each January, at a higher and more predictable monthly cost. It is not free of homework — the drug plan still needs checking every year — but it is a smaller pile of homework. Advantage versus Medigap is the honest comparison, and switching from Advantage to a supplement in Arizona covers the part people underestimate: outside a guaranteed-issue situation, Arizona has no birthday rule and a supplement application goes through medical underwriting.

If the letter says the plan is going away

That is a different notice with a different rule behind it. An organization that is not renewing must notify each Medicare enrollee by mail at least 90 calendar days before the nonrenewal takes effect, and must also provide information about other options available in the region — a written description of alternatives, outbound calls, or similar.

Two things follow. First, you are not stuck: a plan leaving your area is among the situations Medicare treats as a guaranteed issue right for buying a Medicare Supplement, which is the one time of life that door opens without health questions for many people. Second, it is time-limited, and the clock starts without waiting for you to notice. If a nonrenewal notice arrives, that is the week to make a plan, not the week to file it in a drawer.

The short version

• The Annual Notice of Change must reach you by September 30 — that is 35 days from today — and the Evidence of Coverage by October 15.
• It compares this year to next, side by side: premium, deductibles, copays, out-of-pocket maximum, drug list, pharmacy and provider networks, extra benefits.
• Read it in this order: drug list, out-of-pocket maximum, network, your own copays, premium, extras.
• It will not name your doctor. Call the practice and ask whether they are contracted for next year — as a separate question from whether they take the plan today.
• Doing nothing renews you into next year’s version of the plan, not this year’s.
• Nothing in the letter can be acted on until October 15, and the window shuts December 7.
• A nonrenewal is a separate letter with at least 90 days’ notice, and it can open a guaranteed-issue path to a supplement.

If you would rather read it with someone

Bring me the letter. Running your prescriptions, your doctors and your pharmacy against every plan offered in your ZIP — and reading what the letter actually changed rather than what the headline says — takes about twenty minutes with someone who does it weekly, and considerably longer alone at the kitchen table with a highlighter.

There is no charge for it, and I have no interest in moving you off a plan that still fits. Most years, for most of the households I see, the answer is that the plan still works and the reading was the point.

The office is in Anthem, about 25 minutes from north Peoria out the Carefree Highway and down Lake Pleasant Parkway, and most of this gets done by phone anyway. Call (602) 844-6002 or book a time — and if you call or text, that is your consent for me to reply the same way.

September is the month for this. Not December 5.