By September 30, federal law requires your insurance provider to send your Medicare Annual Notice of Change (ANOC) letter by mail or email. You might be tempted to treat this thick envelope like junk mail, but it is the most important healthcare document you will receive all year.
For anyone enrolled in a Medicare Advantage plan or Part D plan, reviewing your ANOC’s critical coverage and cost updates can help you avoid surprise expenses or losing access to your primary doctors on January 1.
The ANOC Checklist: What to Scrutinize
It’s important to take a good, long look at your ANOC letter.
“Medicare Advantage plans, as well as Medicare prescription drug plans, are annual plans, meaning most — if not all — will have some degree of changes from year to year,” says Brandon Hill, a senior financial advisor and Medicare specialist at Beckett Financial Group in West Columbia, South Carolina. “ANOCs are helpful tools that put the current year’s benefits next to the following year’s benefits so you can see a simple side-by-side comparison of both years.”
There are several important things you’ll want to take a look at, including:
— Financials. Review changes to your premiums, deductibles and maximum out-of-pocket (MOOP) limits. If your MOOP increases beyond what you feel comfortable paying, consider shopping for a different Medicare Advantage plan.
— Drug coverage. Formulary tiers can change annually, which can raise your out-of-pocket costs for both generic and brand-name medications. Under the Inflation Reduction Act, out-of-pocket Part D prescription drug costs are capped annually — set at $2,000 in 2025, $2,100 in 2026 and an estimated $2,400 in 2027 based on federal cost-indexing formulas.
— Provider networks. You’ll want to confirm that your doctors and pharmacies are still in your network. If they’re not, and you like your physicians and drugstore, you’ll probably want to try and find a new Medicare Advantage plan.
— Supplemental benefits. Watch for reductions in dental, vision, hearing or over-the-counter (OTC) allowances.
[READ: When Am I Eligible for Medicare? Age Rules, Timeline & How to Enroll]
How the ANOC Differs by Plan Type
Your type of Medicare coverage determines which type of ANOC letter you will or will not receive.
— If you have original Medicare or Medigap, you won’t receive an ANOC letter. That’s because Medicare benefits are federalized, and generally, there are not a lot of major changes every year that warrant these bulky ANOC letters. In addition, while Medigap policies do not issue calendar-year ANOC letters, premium adjustments for Medicare supplement plans typically occur on your individual policy anniversary date or state-designated adjustment timeline.
— If you have a Medicare Advantage plan, you’ll receive an ANOC. Medicare Advantage plans evolve year to year, thanks to inflation, fluctuating healthcare costs and changing regulations, among other reasons.
— If you have a Medicare Part D prescription plan, you’ll also receive an ANOC. Your letter will focus solely on changes to the drug list, including tier reclassifications and drug removals.
[READ: Medicare Part D Costs in 2026: Premiums, Deductibles, Tiers and $2,100 Cap]
Key Medicare Annual Notices and Disclosures Compared
| Document Name | Delivery Window | Document Scope | Key Audit Focus Examples |
| Annual Notice of Change | By September 30 | Concise summary (10-30 pages) | Premium increases, tier shifts for prescriptions, dropped doctors |
| Evidence of Coverage | Typically September or October | Comprehensive manual (100 or more pages) | Formal prior authorization rules, detailed benefit limits, claims procedures and appeal protocols |
| Medicare Summary Notice | At least twice per year | Processed claims statement | Billing accuracy verification, out-of-pocket spending tracking, medical identity theft checks |
[SEE: How to Avoid Medicare Fraud]
Action Steps: What to Do After Reading
Reading your ANOC letter is half the battle.
“Don’t throw it away,” says William Gray, founder of The Medicare Dude, an independent Medicare insurance agency based in Jacksonville, Florida.
Far too many beneficiaries discover in January that their doctor is out of network simply because they ignored the notice when it arrived in September.
If you have the ANOC letter, here’s what to do.
Step 1: Compare the ANOC to your current 2026 baseline
Compare your current Medicare Advantage plan or Part D coverage terms side-by-side with next year’s updates. The ANOC letter clearly lays out cost comparisons, making it easy to identify upcoming changes to monthly premiums, covered drugs and medical networks.
“Each line needs to be looked at through the lens of, ‘If this is my year for everything to break, can I afford what’s on the table here?'” Gray says.
If a sudden health downturn would make your plan unaffordable, shop around to find a more cost-effective Medicare Advantage plan or Part D option.
Gray encourages beneficiaries to read the document thoroughly.
“The ANOC is one of the best teaching tools you’ll receive all year because it’s your own plan telling you what’s changing,” Gray says.
Watch for new administrative hurdles — such as new prior authorization rules for prescriptions or new specialist referral requirements — that could disrupt how you access care.
Step 2: Prepare for October 1 (When the Plan Finder reflects 2027 data)
After receiving your ANOC letter in late September, visit Medicare.gov on October 1 when the Medicare Plan Finder tool updates with 2027 coverage data. This tool lets you preview and compare new health and prescription drug plans for the upcoming year.
The period between October 1 and October 15 — known as the “window shopping” period — allows you to evaluate your coverage choices before the annual enrollment period officially opens on October 15.
Step 3: Jot down key dates on your calendar
You’ll want to jot down the following dates:
— October 15: Annual enrollment period (AEP) starts. This is when you make changes to your health and drug plans for the following year. Keep the plan you’ve got, or get rid of it and join a new plan.
— December 7: Final day of AEP
— January 1: New coverage begins as the Medicare Advantage open enrollment period opens. During this window, you can switch Medicare Advantage plans once or return to original Medicare. If returning to original Medicare, enroll in a standalone Part D plan immediately to maintain continuous creditable coverage and avoid permanent late enrollment penalties. (Note: You cannot switch from original Medicare to a Medicare Advantage plan during this period.)
— March 31: Final day of the open enrollment period
If tracking these deadlines feels overwhelming, you can consult a licensed Medicare agent at no cost.
“During the annual election period of October 15 to December 7, an agent can assist you in making sure you’re covered to the best of your ability and are maximizing your bang for the buck with your plan for the following year,” Hill says.
Frequently Asked Questions
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How to Read Your Medicare ANOC Letter for 2027 Coverage originally appeared on usnews.com
