You do not have to enroll in Medicare, but there are real costs to waiting

Medicare enrollment is not mandatory, but delaying it after you become may be able to access usually means paying a permanent penalty on your premiums. If you have health coverage through your job or a spouse's job, you may be able to delay Part B (medical insurance) without penalty — but you still need to understand the rules, because the exceptions are narrow and the penalty is steep.

The key question is whether you have creditable coverage — health insurance that is at least as good as Medicare Part B. If you do, you can turn down Medicare without penalty. If you do not, every month you go without Part B after you turn 65 costs you 10 percent more in premiums for the rest of your life.

Key Takeaways

  • You can refuse Medicare, but if you do not have creditable coverage through work or a spouse's job, you will pay a permanent 10 percent penalty on Part B premiums for every 12 months you delay.
  • Creditable coverage means your current health plan is at least as good as Medicare Part B — your employer or union can tell you in writing whether yours qualifies.
  • If you have creditable coverage and delay Medicare, you must enroll within eight months of losing that coverage or face the same penalty.
  • Part A (hospital insurance) has no penalty for delay if you are 65 or older and not working, but you should still enroll to avoid gaps in coverage.
  • The penalty applies only to Part B and Part D (prescription drug coverage), not to Part A, and it never goes away even after you finally enroll.

What creditable coverage actually means

Creditable coverage is not just any health insurance — it has to be as comprehensive as Medicare Part B. Your employer's health plan, a spouse's plan, or coverage through a union usually qualifies. Medicare itself, Medicaid, TRICARE (military coverage), and the Veterans Health Administration all count as creditable.

Your employer or union is required by law to tell you in writing whether your plan is creditable. Ask for this letter in writing and keep it. You will need it later if you ever have to prove you had creditable coverage when you delayed Medicare. If your employer cannot or will not give you a written statement, that is a sign the coverage may not may have access to.

Short-term health plans, discount plans, and plans that cover only specific services (like dental-only or vision-only) do not count as creditable coverage. Neither does coverage you buy on your own through the health insurance marketplace, even if it is comprehensive.

The penalty for delaying Part B without creditable coverage

If you turn 65 and do not have creditable coverage, you have a seven-month window called your Initial Enrollment Period to sign up for Part B without penalty. This window starts three months before the month you turn 65 and ends three months after. If you miss this window and do not have creditable coverage, the penalty begins.

The penalty is 10 percent of the standard Part B premium for each full 12 months you did not have Part B. If you delay for two years, your premium goes up 20 percent. If you delay for five years, it goes up 50 percent. This increase stays with you for as long as you have Medicare — it does not go away after a few years.

The standard Part B premium changes every year. In 2024, the standard premium was $164.90 per month for most people, though some higher-income beneficiaries pay more. A 10 percent penalty would add roughly $16.49 per month permanently. Over ten years, that is nearly $2,000 in extra costs.

When you can delay Part B without penalty

If you have creditable coverage through your job or your spouse's job, you can turn down Part B when you turn 65. You do not need to enroll until you lose that coverage or stop working, whichever comes first. This is called the Special Enrollment Period, and it gives you eight months from the date your coverage ends to enroll in Part B without penalty.

The catch is that you must enroll within that eight-month window. If you wait nine months, the penalty kicks in. Some people miss this important date because they do not realize they need to act — they think Medicare will automatically enroll them or that they have more time. It will not, and you do not.

If you are still working at 65 and have health coverage through your employer, you can also delay Part A (hospital insurance) without penalty. However, you should still enroll in Part A even if you delay Part B, because Part A has no premium if you or your spouse paid Medicare taxes for at least ten years. Enrolling in Part A costs you nothing and protects you if you need hospital care.

Part D (prescription drug coverage) has its own penalty

Part D is optional, just like Part B, and it has its own separate penalty for delay. If you go 63 or more days without creditable prescription drug coverage after you become may be able to access for Medicare, you pay a permanent penalty when you finally enroll in Part D.

The penalty is roughly 1 percent of the national average Part D premium for each month you were without coverage. If you delay for one year, the penalty is about 12 percent. Like the Part B penalty, this increase stays with you for life.

If your current health plan includes prescription drug coverage that is at least as good as Medicare Part D, you can delay Part D without penalty. Again, ask your employer or plan for written confirmation that your coverage is creditable.

What happens if you miss your enrollment window

If you miss your Initial Enrollment Period and do not have creditable coverage, you can still enroll in Medicare during the General Enrollment Period, which runs from January 1 to March 31 each year. Your coverage would start July 1 of that year. However, you will owe the penalty for every month you were not enrolled.

There is one exception: if you can show that you had a circumstance that prevented you from enrolling on time — such as a serious illness, a language barrier, or incorrect information from Social Security — you may be able to request a Special Enrollment Period outside the normal windows. This is rare and requires documentation, but it is worth asking Social Security about if you have a legitimate reason for the delay.

Part A enrollment if you are not working

Part A is hospital insurance, and it is free if you or your spouse paid Medicare taxes for at least ten years. You do not have to enroll in Part A, but there is little reason not to. It has no premium and no penalty for delay if you are 65 or older and not working.

However, if you delay Part A and then need hospital care, you will have a gap in coverage. Part A covers hospital stays, skilled nursing facility care, hospice, and some home health services. Without it, a single hospitalization could cost tens of thousands of dollars out of pocket.

Frequently Asked Questions

Can I refuse Medicare entirely and keep my employer coverage instead?

Yes, if your employer coverage is creditable. However, you must enroll in Medicare within eight months of losing that coverage. If you wait longer, you will pay a penalty on Part B and Part D for the rest of your life, even if you eventually enroll.

What if my employer says my coverage is creditable but I am not sure?

Ask for the statement in writing. If your employer cannot provide one, contact your plan's customer service and ask directly whether the plan meets Medicare's standards for creditable coverage. You can also call Social Security at 1-800-772-1213 to ask whether a specific plan qualifies.

Do I have to enroll in all parts of Medicare or can I pick and choose?

You can enroll in Part A without Part B, or Part B without Part A, though Part A is usually free so there is no reason to skip it. Part D is separate and optional. However, if you delay any part without creditable coverage, you pay a penalty on that part when you finally enroll.

What if I turn 65 while still working full-time?

If you have health coverage through your job, you can delay Part B without penalty. You should still enroll in Part A, which is free and has no penalty for delay. When you retire or lose your job coverage, you have eight months to enroll in Part B penalty-free.

Does the penalty ever go away?

No. The penalty is permanent and applies to every premium payment for as long as you have Medicare. This is why it is important to understand the rules before you turn 65 — a small mistake in timing can cost you thousands of dollars over your lifetime.