Medicare open enrollment 2027 brings tax questions to ask

Medicare open enrollment runs from Oct. 15 through Dec. 7 each year. If you want to change your Medicare health or drug coverage for 2027, your plan generally must receive your request by Dec. 7, 2026. Changes take effect Jan. 1, 2027. Even if you like your current plan, it's worth checking what may change before deciding to stay put.

Who should review their coverage?

If you have a Medicare Advantage or Medicare Part D prescription drug plan, read its Annual Notice of Change (ANOC). Your plan may change what you pay or which medications and providers it covers, so the plan that worked for you in 2026 may not be the best fit for 2027.

This annual window is different from enrolling in Medicare for the first time. It's also different from the January-March Medicare Advantage open enrollment period and ACA Marketplace enrollment.

What can you change during open enrollment?

Depending on your current coverage, you can switch between original Medicare and a Medicare Advantage plan, change Medicare Advantage plans, or join, drop or switch a standalone Part D drug plan. If you're considering a return to original Medicare, check your eligibility for Medicare Supplement Insurance (Medigap) before switching. You may not have a guaranteed right to buy a Medigap policy.

Before making a decision, compare how your plan will work next year:

• Prescription costs: Are your medications still covered, and have their costs or coverage restrictions changed?
• Providers and pharmacies: Will your preferred doctors and pharmacies still participate in the plan?
• Premiums and other expenses: How do the deductible, copays and likely out-of-pocket costs compare?
• Prior authorization: Will services you expect to use require approval from the plan?

Use Medicare Plan Compare to evaluate available plans. For free, personalized help choosing coverage, contact your State Health Insurance Assistance Program (SHIP); a tax preparer isn't necessarily an insurance plan adviser.

Even when you've settled on your coverage of choice, Medicare can still affect your taxes.

How Medicare affects your tax picture

Medicare coverage decisions aren't the same as tax decisions, but several Medicare rules make a tax conversation worthwhile:

• Higher-income premiums: The income-related monthly adjustment amount (IRMAA) can increase Part B and Part D premiums. Social Security generally uses income from a tax return two years earlier, so 2025 income generally affects 2027 premiums. Certain qualifying life-changing events may support a request for a new determination.
• Medical expense deductions: Medicare Part B and Part D premiums can count as medical expenses, but for taxpayers who itemize, only total eligible unreimbursed expenses above 7.5% of adjusted gross income (AGI) are deductible. Certain self-employed taxpayers may qualify for a separate health insurance deduction.
• HSA contributions: Enrolling in Medicare ends eligibility to contribute to a health savings account (HSA) for the affected months. Retroactive coverage can complicate contribution limits, particularly for someone enrolling after age 65 (see NATP's example of how Medicare enrollment affects HSA contribution limits).
• Existing HSA savings: At age 65 or older, HSA funds may generally pay certain Medicare premiums tax-free, including Parts B and D. Medigap premiums do not qualify for that HSA premium exception.

These tax rules don't necessarily change when you switch Medicare plans during annual open enrollment, but they do help explain why your income history and HSA records may deserve attention at tax time.

Your Medicare enrollment and tax checkpoint

• Before Dec. 7, compare your ANOC with your prescriptions and preferred providers using Medicare's plan tools.
• If a premium adjustment seems tied to income, have your Social Security notice and 2025 tax return ready for a tax discussion.
• If you're newly enrolling in Medicare or have questions about deductions, bring your HSA contribution records and Medicare premium information.
• For coverage choices, start with Medicare or SHIP.

If Medicare premiums or HSA contributions raise questions about your taxes, use NATP's Find a Tax Pro directory to find a professional who can help you determine what belongs on your return.