Turning 65 changes how your health coverage works, whether you keep working or retire. For employees with employer coverage, Medicare eligibility triggers a set of rules that affect premiums, out-of-pocket costs, and even your savings. Get it wrong and it costs thousands. Get it right, and healthcare becomes a wealth-building tool.
When to Enroll in Medicare at 65
At age 65, you get a decision window different from open enrollment. If you're still working and have group health through an employer with 20 or more employees, you can delay Medicare enrollment without penalty. But once that employment ends, you have a Special Enrollment Period (SEP) of eight months to sign up for Medicare Part B, or face permanent late-enrollment penalties. That clock starts when your job or your employer coverage ends, whichever comes first; COBRA does not extend it.
For employers with fewer than 20 employees, Medicare pays first at 65 and the employer plan becomes secondary. You generally need Medicare Parts A and B even while still working, because a small-employer plan is not your primary coverage in this situation. Costs Medicare does not cover can fall to you.
What Changes With Your Employee Benefits
Premium Contributions
Once you enroll in Medicare, you start paying Part B premiums, typically deducted from your Social Security check. In 2026, the standard Part B premium is $202.90 a month. Your employer may stop contributing to your health coverage, or you may lose subsidies for prescription drug plans. Your employer may no longer subsidize a large portion of your medical costs.
Out-of-Pocket Maximums and Deductibles
Original Medicare (Parts A and B) has no annual out-of-pocket maximum, unlike most employer plans. Without a Medigap or Medicare Advantage plan, your financial exposure on medical services has no cap. Employer plans typically cap your annual liability at $10,600 for self-only coverage in 2026 under ACA rules; Medicare Parts A and B carry no such cap. Part D works differently. Since 2025, covered prescription costs have a hard annual cap of $2,000, indexed to $2,100 in 2026. You'll still want to weigh Original Medicare with a supplement against Medicare Advantage to manage the medical-side exposure.
Prescription Drug Coverage
Your employer plan's pharmacy benefit ends when you go on Medicare. You'll need a standalone Part D drug plan for Original Medicare, or a Medicare Advantage plan that includes drug coverage. This is where employees often lose access to low-cost generics or manufacturer discounts. Money already in your HSA can pay, tax-free, for Medicare Part B and Part D premiums, deductibles, and copays, but not Medigap premiums. FSA funds generally cannot be used for insurance premiums. And once you enroll in any part of Medicare, including premium-free Part A, you can no longer make new HSA contributions. Because Part A coverage can be retroactive up to six months, stop contributing about six months before you plan to enroll.
Higher Income Raises Your Medicare Premiums
Medicare premiums are income-tested, and standard budget math often misses this. If your modified adjusted gross income from two years earlier tops $109,000 for an individual or $218,000 for a married couple filing jointly, you pay an income-related monthly adjustment amount (IRMAA) on top of the standard Part B premium. For 2026, high earners pay a total Part B premium of $284.10 to $689.90 a month, plus a Part D surcharge of $14.50 to $91.00 a month. The lookback uses the tax return from two years prior, so a large withdrawal or Roth conversion this year can raise your Medicare premiums two years out. If your income sits above those thresholds, add the surcharge to your monthly budget.
Building Wealth Through Prevention After 65
But this shift doesn't have to be only about higher costs. With a system like WellthCare, Medicare eligibility becomes a wealth-building moment. Verified preventive actions, such as annual wellness visits, cancer screenings, and medication management, earn reward dollars at the WellthCare Store and trigger automatic retirement contributions funded by employer-committed savings. That's what we call “Healthcare that pays you back.”
At Medicare age, three things happen:
- Preventive care at $0 copay. Services cost you nothing, so minor health needs don't add to your out-of-pocket spending.
- Reward dollars at the WellthCare Store. Earned for screenings and prevention, usable on FSA-eligible products, from vitamins to durable medical equipment.
- Automatic retirement contributions. Each time you complete a qualifying health action, employer-committed savings land in a SEP or similar retirement vehicle and compound over time.
This flips the typical Medicare experience. Instead of only managing costs, you're building wealth as you age.
How to Prepare for the Transition
To avoid gaps and maximize benefits, consider these steps before you turn 65:
- Review your employer's coordination of benefits. Does your company require you to enroll in Medicare Parts A and B at 65? Or can you delay?
- Check if your employer offers a Medicare-eligible benefit system. Some innovative employers now provide a health-to-wealth platform that rewards prevention even after you leave the group plan. WellthCare Medicare™ is a dedicated Medicare solution that keeps employees inside the same Health-to-Wealth system after 65, with $0 co-pay care, earned store dollars, and automatic retirement contributions.
- Understand the timeline. You have a seven-month Initial Enrollment Period around your 65th birthday month. It runs three months before your birthday month, the month you turn 65, and three months after. Miss it and face permanent late penalties.
- Evaluate Medigap vs. Medicare Advantage. Medigap offers more predictable out-of-pocket costs; Advantage plans include extras like dental, vision, and gym memberships, but with network restrictions.
- Calculate your total healthcare budget. In 2026, the standard Part B premium is $202.90 a month and the average Part D plan runs about $35. Add a supplement or an Advantage plan premium, and monthly costs can land between $300 and $500. Factor that into your retirement income planning.
What the Transition Means for Your Wealth
Medicare eligibility changes your financial picture. Traditional employer plans largely stop subsidizing your care, and you move into a system with higher exposure and more complexity. An employer that adopts a Health-to-Wealth Benefit System like WellthCare changes that math. Your preventive habits earn reward dollars at the WellthCare Store, your out-of-pocket costs drop, and your retirement wealth grows automatically. At 65, the goal is to keep your health building wealth for the next 30 years.