Medicare Open Enrollment runs October 15 through December 7 each year, where you have the opportunity to change your Medicare Advantage or prescription drug coverage for the January 1 that follows.
That window also arrives alongside retirement income, tax, and authority questions that feel related but run on their own clocks entirely.
I'll use an example couple called the Rostamis (a composite, not a real family). They chose a plan before December 7 and assumed related IRMAA and Medigap concerns were taken care of. They weren't.
At Advocate Wealth Solutions, our planning runs through The PILOT Process™: Portfolio Positioning, Income & Tax Strategy, Longevity & Life Event Stress Testing, Ownership & Control, and Transfer of Risk. Here's how the Medicare Open Enrollment season shows up in that process.
This is education about how the rules connect, not a prediction of any household's result.
How Does a Medicare Plan Change Affect Your January Budget?
A Medicare Advantage or drug plan change shifts how medical and drug costs show up in your budget starting in January. Plans send an Annual Notice of Change (ANOC) every September describing the premium, deductible, coverage, and network changes that take effect in January. If you do nothing during Medicare Open Enrollment, your coverage continues automatically, with those changes intact.
That makes the ANOC a budgeting document as much as a health document. No enrollment choice can promise lower total spending; costs move with premiums, deductibles, networks, and drug lists. But reading the notice means January's numbers aren't a surprise.
What Is IRMAA, and How Does It Affect Your Medicare Premiums?
IRMAA, the income-related monthly adjustment amount, is a surcharge that can raise your Medicare Part B and Part D premiums when your modified adjusted gross income crosses published thresholds. It is a tax-driven clock, separate from the Medicare Open Enrollment calendar, and switching plans during Open Enrollment does nothing to change it.
Key IRMAA figures for 2026 (opens a separate site in a new tab):
- The standard Part B premium is $202.90.
- The first income-related threshold for an individual tax return sits above $109,000.
- The first income-related threshold for a joint tax return sits above $218,000.
- Social Security generally uses the tax return from two years earlier, so 2026 premiums generally reflect 2024 income.
Changing plans doesn't change that lookback. Planning that touches Medicare premiums runs on tax-year timing, not on the October 15 Open Enrollment start date.
Does Enrolling in a Medicare Plan Update Your Beneficiaries?
No. If an adult child may someday need to help with an enrollment decision, Medicare's guidance looks for an authorized representative: someone legally able to act for you under state law. That role isn't automatically filled by the person named in a financial power of attorney, and it's distinct from a Social Security representative payee.
Can You Buy a Medigap Policy After Leaving Medicare Advantage?
Not always. Leaving Medicare Advantage for Original Medicare during Medicare Open Enrollment is allowed, but buying a Medigap policy afterward isn't guaranteed. Medicare describes limited trial rights, such as a single 12-month window to get your old Medigap policy back if you dropped it to join Medicare Advantage for the first time. Outside those situations, Medicare warns you may not be able to get the same policy, or in some cases any Medigap policy at all. State rules differ.
A gap between leaving Medicare Advantage and starting Medigap coverage can leave you exposed to cost-sharing you didn't plan for. Deciding which risks to keep and which to transfer to an insurer means sequencing the change: know what's guaranteed and what isn't before you disenroll.
A Year-End List
Put four things on one list: your Annual Notice of Change, your Medicare Open Enrollment decision, your Medicare premium notice with its tax year written on it, and the authority papers someone would need to act for you.
If walking that list together is worth a conversation, the place to start is a Clarity Map Session: 30 minutes, no cost, no obligation, and you keep the map either way.
Frequently Asked Questions
Does Medicare Open Enrollment affect my IRMAA surcharge?
No. IRMAA is based on your modified adjusted gross income from two years prior, not on which Medicare plan you choose during Open Enrollment. Changing plans has no effect on this separate, tax-driven calculation.
Can I change my Medicare Advantage plan more than once a year?
There is also a Medicare Advantage Open Enrollment Period, from January 1 through March 31, that allows a one-time plan switch or a return to Original Medicare for those already enrolled in Medicare Advantage. This is distinct from the October 15 to December 7 window and does not reopen Medigap guarantees.
Who can legally help me make Medicare enrollment decisions if I'm unable to?
Medicare requires an authorized representative, a role defined under state law, which is separate from a financial power of attorney or a Social Security representative payee. Confirming this designation before you need it is part of our planning process.
Educational information only, not legal, tax, or investment advice, and not a guarantee of any particular outcome. Medicare rules and costs change and every household is different; talk with your own tax professional and financial advisor about your situation. Advocate Wealth Solutions is a registered investment adviser.
Published October 15, 2026. Tax law, contribution limits and thresholds change, so read any figure here as of that date. None of it is advice about your own situation. Advocate Wealth Solutions is a fee-based planning firm in Dublin, Ohio, and a Clarity Map Session is where questions about your own accounts get answered.
