If you're turning 65 and still working—or your spouse is—navigating Medicare can be a little more complex. Understanding how Medicare works alongside your existing health insurance is key to avoiding gaps in coverage and unexpected penalties.

Do You Have to Enroll in Medicare at 65?

Most people become eligible for Medicare when they turn 65. Many choose to sign up for both Part A (Hospital Insurance) and Part B (Medical Insurance) at that time. Signing up late can result in penalties or a lapse in coverage, but in some cases, it’s perfectly reasonable—and even beneficial—to delay enrollment.

You may qualify for a Special Enrollment Period (SEP) if you miss your initial window, especially if you’re still covered by employer insurance.

Who Gets Part A Without Paying a Premium?

If you or your spouse paid Medicare taxes for at least 10 years, you likely won’t pay a premium for Part A. You can sign up as early as three months before your 65th birthday and at any point afterward. If you delay, your Part A coverage may be retroactive for up to six months—so be aware of how this could affect other financial planning, like Health Savings Accounts (HSAs).

To check your eligibility, log into your my Social Security account or speak with your employer.

If You or Your Spouse Has Job-Based Health Insurance

When you're still working at 65 and covered by group health insurance through your (or your spouse’s) employer, you may be able to delay enrolling in Medicare Part B without a late penalty.

1. If the company offers group health insurance to all employees, you can choose to sign up for Part A at 65 (if it’s premium-free) and wait to enroll in Part B until you retire or lose coverage.
2. You’ll get an 8-month Special Enrollment Period once you stop working or lose insurance—whichever happens first. During this time, you can enroll in Part B without penalty.
3. It's important to check with your employer: Some job-based plans may not cover costs if you don’t enroll in Medicare when first eligible.

If You're Self-Employed or Your Coverage Isn’t Through a Standard Employer Plan

If you're self-employed or your insurance isn’t offered to all employees (like retiree coverage or a stipend-based plan), you should confirm whether your plan qualifies as employer group health coverage under IRS rules. If not, it's best to enroll in Medicare at 65 to avoid penalties.

For retiree coverage, check with your benefits administrator. Some plans won’t pay for services unless you’re enrolled in both Part A and Part B. Joining a Medicare plan that your former employer doesn’t sponsor might even cause you to lose retiree benefits altogether, so review your options carefully.

If Your Insurance Isn’t From an Employer

Health insurance from the Marketplace, Medicaid, or a private plan works differently from employer insurance. These plans often require you to sign up for Medicare when you’re first eligible. If you delay, you could face late enrollment penalties or lose some of your current benefits. Contact your insurer directly or use Medicare’s tool to find out what applies to your situation.

If You Have COBRA Coverage

COBRA lets you keep your job-based coverage temporarily after employment ends. However, it doesn’t count as creditable coverage for delaying Medicare Part B:

1. If you’re turning 65 and have COBRA, enroll in Medicare during your initial eligibility period. Waiting could mean penalties and coverage gaps.
2. If you get COBRA after enrolling in Medicare, Medicare will pay first, and COBRA second.
3. Don’t rely on COBRA to delay Medicare enrollment—doing so could lead to costly consequences.

No Insurance at 65?

If you're still working but don’t have any health coverage, sign up for both Part A and Part B when you become eligible. Delaying could result in long-term penalties. If cost is a concern, you may qualify for programs that help pay for premiums and out-of-pocket expenses.

When and How to Sign Up for Medicare

Enrollment depends on whether you already have Part A or are signing up for both Part A and Part B. Visit Medicare.gov to get the correct forms and start the process.

Planning ahead is essential:

1. Sign up about a month before your employer coverage ends to avoid any gap.
2. Talk to your HR department or benefits administrator to understand your plan’s rules.
3. If you contribute to an HSA, stop making contributions at least 6 months before you apply for Medicare or Social Security benefits to avoid tax penalties.

What About Prescription Drug Coverage?

Once you have Medicare, you can choose additional coverage like a drug plan (Part D) or Medicare Advantage. If you already have creditable drug coverage, you can delay enrolling in Part D without a penalty.

Each year, your plan should tell you whether your current drug coverage is considered creditable. Keep that documentation in case you need to enroll in Medicare Part D later.

Final Thoughts

Working past 65 gives you more choices when it comes to Medicare, but it also adds complexity. Whether you're covered through your employer, self-employed, or using private insurance, the key is to understand how your current coverage interacts with Medicare. Reviewing your options carefully—and asking the right questions—will help you avoid penalties and ensure you stay covered.