The September envelope
The Annual Notice of Change: five numbers that decide your next year
Short answer: your Annual Notice of Change (ANOC) arrives each September and lists everything your Medicare Advantage or Part D plan will change on January 1: premium, deductibles, copays, drug tiers, network, and out-of-pocket maximum. Fifteen minutes with five numbers tells you whether to stay or shop during the October 15 to December 7 window. Here’s exactly where to look.
Key takeaways
- The ANOC arrives by September 30 from every Medicare Advantage and Part D plan, showing side-by-side current-year vs. next-year terms.
- Five numbers decide most cases: premium, drug deductible, out-of-pocket maximum, your drugs’ tiers, and your doctors’ network status.
- Formulary and tier moves are the most expensive changes and the easiest to miss.
- If anything moved against you, the fix window is October 15 to December 7, effective January 1.
- No response is required to keep your plan; silence means automatic renewal under the new terms.
What the ANOC is, and isn’t
Federal rules require every Medicare Advantage and Part D plan to send current members an Annual Notice of Change by September 30, laying out next year’s terms next to this year’s. It is not junk mail, though it’s formatted like it, and it is not a bill or a decision you must respond to. It’s the plan telling you, in advance and in writing, how the deal changes January 1. Every January forum post that begins "suddenly my copay tripled" describes something that was printed in a September envelope.
If you can’t find yours, log into your plan’s member portal or call the number on your card and ask for it; plans must provide it.
The five numbers that decide most cases
| Number | Where it hides | What "bad" looks like |
|---|---|---|
| Monthly premium | First summary table | Any jump you weren’t expecting, including a $0 plan gaining a premium |
| Drug deductible | Part D section | Moving from $0 toward the federal maximum (which is $615 in 2026) |
| Out-of-pocket maximum | Medical costs table | A higher ceiling on your worst-case year |
| Your drugs’ tiers | Formulary change list | A drug moving up a tier, gaining prior authorization, or leaving the formulary |
| Your doctors’ status | Network directory (check separately) | "No longer in network" for anyone you actually see |
The ANOC shows plan-level changes; individual network status is best confirmed against the plan’s next-year directory or a call to the doctor’s office.
The quiet traps
- Tier migration. The premium holds steady, the formulary page shows your daily medication moving from tier 2 to tier 3, and your year quietly costs $600 more. Formulary changes are the highest-dollar item in most ANOCs and the least read.
- New prior authorization flags. A drug or service you use gaining a "PA" marker means paperwork between you and each refill or procedure starting January.
- Benefit swaps. Extras like dental allowances get advertised loudly when added and shrunk quietly in the tables. Verify any extra you actually use.
- Pharmacy network shifts. Your pharmacy dropping from "preferred" to "standard" changes your copays without changing anything else on the page.
- The out-of-pocket maximum creep. Nobody plans to hit it, which is why it moves with the least resistance. It’s the number that defines your bad year.
A worked read-through
Say your ANOC shows: premium unchanged at $0, drug deductible rising from $150 to $350, your blood-pressure drug moving tier 2 to tier 3 ($47 to $90 per fill), out-of-pocket max rising $400, doctors unchanged. Quick math: $200 more deductible plus roughly $516 more in tier copays across the year, before the higher ceiling. That "unchanged $0 plan" costs about $700 more next year, and every dollar of it was disclosed. That’s a shop-during-AEP verdict, reached in ten minutes with a highlighter.
The habit that makes this easy: staple a one-line note to each year’s ANOC: "Checked premium, deductible, OOP max, drugs, doctors. Verdict: stay / shop." Next September you’ll have a baseline instead of a mystery.
If you don’t like what you find
Your window is the Annual Enrollment Period, October 15 to December 7, effective January 1. Run your drug list through Medicare.gov’s plan finder sorted by total annual cost, compare the best result against your plan’s new terms (not the old ones you remember), and switch if the gap is real. Advantage members also get a fallback window, January 1 to March 31, for one switch if January reveals something the paperwork didn’t.
Questions people also ask
What is the Annual Notice of Change?
Do I have to respond to the Annual Notice of Change?
What should I check first in my ANOC?
My plan’s premium didn’t change. Am I safe?
I never received an ANOC. What do I do?
Sources for this article
- Medicare.govMedicare Plan Finder: the comparison tool for acting on what the ANOC discloses.
- Medicare.govMedicare.gov: plan materials, rights, and enrollment window rules.
- CMS.gov2026 premiums and deductibles: the federal maximums that plan-level numbers move within.
Figures checked against these sources in July 2026. We update within weeks when CMS publishes new amounts.