One of the most important pieces of mail a Medicare enrollee gets all year lands around now, and it is easy to toss unread. By September 30, every Medicare Advantage and Part D plan must send each member an Annual Notice of Change spelling out what their coverage and costs will look like next year. Reading it is how a person catches a dropped benefit or a rising cost before it hits.
What the notice is
The Annual Notice of Change, often called the ANOC, is a document plans are required to send members each year describing how the plan will change for the coming year. Medicare Advantage and Part D drug plans must deliver it by September 30, timed to reach members before enrollment season.
It lays out next year’s premiums, deductibles, copays, and coverage details, and flags changes from the current year. In effect, it is the plan telling members exactly what will be different in the year ahead.
Most people receive it by mail in the last weeks of September, sometimes alongside the plan’s Evidence of Coverage. It is a routine mailing, which is precisely why it is so often set aside without a look.
Free retirement updates: A quiet rule change can shrink your Social Security or Medicare check, and no one warns you. The free Retirement Shield newsletter catches these early and tells you what to do. Get it free.
Why it is worth reading
The notice matters because plans change every year, and not always in the member’s favor. A premium can rise, a deductible can grow, a copay for a regular medication can jump, or a drug can move to a more expensive tier. The ANOC is where those changes are disclosed.
It can also reveal bigger changes, such as a doctor or hospital leaving the network, a benefit being reduced, or, in some cases, the plan being discontinued entirely. Any of those can significantly affect a member’s costs or care.
Catching a change in September gives a member time to act during the fall enrollment period. Discovering it in January, after it has taken effect, means being stuck with it for the year.
The numbers people miss
The costliest changes are often buried in the details rather than announced on the first page. A modest premium can mask a higher deductible, a change to the out-of-pocket maximum, or a shift in how a specific drug is covered. Those are the figures that determine what a household actually pays.
For someone who takes regular prescriptions, the drug coverage section deserves special attention, since a medication moving to a higher tier or off the formulary can add up quickly over a year. The same goes for copays on frequent doctor or specialist visits.
Comparing this year’s costs to next year’s, line by line, is the way to see the real impact. The notice is designed to make that comparison possible, but only for members who open it and look.
How it connects to enrollment
The ANOC arrives just before Medicare’s Annual Enrollment Period, which runs October 15 through December 7. That timing is deliberate: it gives members a few weeks to review the changes and decide whether to switch plans for the coming year.
During that window, a member can move to a different Medicare Advantage plan, change Part D drug plans, or return to Original Medicare. The ANOC is the information that should drive that decision.
A member who reads the notice, sees an unwelcome change, and shops during enrollment can often find a better fit. A member who ignores it typically ends up automatically staying in the same plan under next year’s less favorable terms.
What to do when it arrives
The practical steps are simple. Open the notice when it comes, compare next year’s premium, deductible, copays, and drug coverage to what you pay now, and check whether your doctors and prescriptions are still covered on good terms. Flag anything that got worse.
If the changes are unfavorable, use Medicare’s plan comparison tool during enrollment to see whether another plan would cost less or cover your needs better. The notice tells you what is changing; the plan finder helps you respond.
Free, unbiased help is available through the State Health Insurance Assistance Program for anyone who finds the notice confusing. The point is not to become an expert but simply to read the document and act on it while there is still time to switch.
A small habit that saves money
The recurring lesson of the ANOC is that a few minutes in September can prevent a year of overpaying. Plans count on inertia, and many members stay put simply because they never opened the notice that would have prompted them to shop.
Building the habit of reviewing the notice each fall, the way one might review any annual statement, turns a piece of easily ignored mail into a real cost-control tool. It is one of the few moments each year when a member can change their coverage.
For a household on a fixed income, catching a rising drug cost or a dropped benefit before it takes hold can be worth hundreds of dollars. The notice is required to arrive by September 30 for exactly that reason, and the benefit only reaches members who read it.
This article was produced with AI assistance and reviewed by a human editor. Figures are linked to their primary sources; where a claim could not be verified from the public record, we say so.
More Financial Reading
