If you're approaching 65, the most important thing to know is this: Medicare has a specific window for signing up, and missing it can cost you for the rest of your life. The good news is that the window is simple once someone walks you through it — and you have help.

Your Initial Enrollment Period

Your Initial Enrollment Period is a seven-month window built around your 65th birthday: the three months before the month you turn 65, your birthday month, and the three months after. This is when most people first sign up for Medicare.

The parts of Medicare, briefly

Medicare comes in "parts." You don't need to memorize them — you just need to know roughly what each one does:

• Part A — Hospital. Inpatient hospital stays, skilled nursing, some home health. Most people pay no premium.
• Part B — Medical. Doctor visits, outpatient care, preventive services. Has a monthly premium.
• Part C — Medicare Advantage. An all-in-one alternative offered by private plans that bundles A, B, and usually D.
• Part D — Prescriptions. Drug coverage, offered through private plans.

How to avoid late-enrollment penalties

If you don't sign up when you're first eligible — and you don't have other qualifying coverage — you can face penalties that are added to your premiums permanently. To stay on the safe side:

• Mark your seven-month window on the calendar now.
• If you're keeping employer coverage past 65, confirm whether it counts as "creditable."
• When in doubt, ask before a deadline passes — not after.

Still working at 65?

If you (or your spouse) have active employer coverage, you may be able to delay parts of Medicare without penalty. Whether that's the right move depends on your plan and your real costs — it's worth a quick conversation before you decide.

This article is educational and reflects general rules drawn from Medicare.gov and CMS.gov. It is not a recommendation of a specific plan, and individual situations vary — please confirm details for your circumstances. Last reviewed: June 2026.