By Whitney Stidom, Vice President of Medicare Enablement, eHealth. 

For more than 57 million Americans enrolled in Medicare Advantage or Medicare Part D plans, September brings with it the Annual Notice of Change letters — at least for people who open their mail.   

The Annual Notice of Change, sometimes referred to as an ANOC, will show up in mailboxes of Medicare Advantage and Part D enrollees by the end of September, detailing how these insurance plans are changing for the coming year.    

But many Medicare beneficiaries will likely ignore or overlook these letters. A new survey of Medicare beneficiaries found that nearly 25% report never having received an ANOC letter while enrolled in a Medicare Advantage plan, while less than half confirm they have received this year’s letter. 

For people enrolled in a Medicare Advantage plan or Medicare Part D prescription drug plan — and their family members — it's important to read this letter, especially this year. The upcoming Medicare Annual Enrollment Period (Oct. 15 to Dec. 7) is expected to bring significant changes to many Medicare plans, including network adjustments, increased cost sharing and the elimination of some plans entirely. 

Here are three steps if you or a loved one received an ANOC and need help better understanding it: 

Changes to your coverage. First, look for any changes to your covered benefits. Some plans might be shutting down for 2026 entirely, but you may also see changes to your list of covered prescription drugs or to some of the supplemental benefits (like dental or vision care, grocery allowance, or gym membership discounts) that were previously offered by your Medicare Advantage plan. 

Pay particular attention to your prescription drug formulary changes. Plans may move medications to different tiers with higher copays, require prior authorization for drugs that were previously covered without restrictions, or remove certain medications entirely. If you take multiple medications, carefully review the formulary changes section to ensure your current prescriptions will still be covered at an affordable cost. 

Changes to your costs. Several cost categories may change in your Medicare plan next year, such as increased premiums, deductibles, or changes to copays and coinsurance for services like prescriptions, office visits, hospital stays and emergency care. 

Beyond the obvious premium changes, look closely at your out-of-pocket maximum limits. These caps on your annual spending can vary significantly and may increase from year to year. Also examine any changes to specialist visit costs, diagnostic tests, and medical equipment and supply coverage, as these can substantially impact your healthcare budget if you require ongoing specialized care for conditions such as diabetes. 

Changes to your provider network. Medicare Advantage plans are offered through private insurers. To help keep premiums as low as possible, these plans use those insurer's networks of doctors and hospitals. These networks can change from one year to another, so it's important to understand if your preferred doctor or clinic or pharmacy will still be "in-network" for the coming year. 

Network changes don't just affect your primary care physician. Review whether your specialists, preferred hospitals, facilities, urgent care centers, and pharmacies remain in-network. Going out of network can result in significantly higher costs or even no coverage at all for non-emergency services. If your current providers are being dropped, contact them to ask if they're joining other Medicare Advantage plan networks that might be available in your area. 

The comparison-shopping season for 2026 coverage begins Oct. 1, with the Medicare Annual Enrollment Period starting Oct. 15. For help, people can work with State Health Insurance Program (SHIP) counselors who are available in every state to provide Medicare beneficiaries and their families with free information about Medicare and help them understand their coverage options. Another option is a licensed insurance agent, who can help people compare plans and offer advice based on personal health needs, preferences and budgets.