Turning 65? Your Step-by-Step Medicare Enrollment Checklist

A complete timeline and checklist for enrolling in Medicare when you turn 65. Don't miss a single step or deadline.

Turning 65 is a milestone that comes with a critical to-do list: enrolling in Medicare. The process has specific deadlines, and missing them can result in lifelong penalties. This step-by-step guide walks you through exactly what to do and when, so you can start your Medicare coverage with confidence.

Your Medicare Enrollment Timeline

Your Initial Enrollment Period (IEP) spans 7 months, centered around the month you turn 65. Here's the exact timeline:

Best Time to Enroll

For coverage starting on the first day of your birthday month, enroll during the 3 months before your birthday month. Enrolling during or after your birthday month delays your coverage start date.

Step-by-Step Enrollment Checklist

Decide whether to take Part A: Most people should enroll in Part A even if they're still working — it's premium-free and covers hospital stays. Exception: if you or your spouse has an HSA, enrolling in Part A requires you to stop HSA contributions.
Determine if you need Part B now: If you have employer coverage through a company with 20+ employees, you can delay Part B without penalty. If your employer has fewer than 20 employees, Medicare becomes primary and you should enroll.
Gather required documents: Social Security number, proof of citizenship or legal residency, and information about any current health coverage.
Enroll online at SSA.gov, by phone at 1-800-772-1213, or in person at your local Social Security office.
Choose your coverage path: Original Medicare (Part A + B) with optional Medigap and Part D, OR Medicare Advantage (Part C) which bundles everything.
If choosing Original Medicare: Shop for a Medigap policy during your 6-month Medigap Open Enrollment Period (starts when you have Part B at age 65+). Also enroll in a Part D drug plan.
If choosing Medicare Advantage: Compare plans available in your area using Medicare.gov or SeniorPop's Benefit Checker.
Confirm your enrollment by checking your status at Medicare.gov or calling 1-800-MEDICARE.
Mark your calendar for future enrollment periods — you can make changes each fall during the AEP.

Special Situations

Still Working at 65 with Employer Coverage

If you're still employed and have health coverage through your employer (or your spouse's employer) with 20 or more employees, you can delay Medicare Part B without penalty. When you or your spouse stop working or lose that coverage, you'll have an 8-month Special Enrollment Period to sign up for Part B.

Receiving Social Security Before 65

If you're already receiving Social Security benefits before you turn 65, you'll be automatically enrolled in Medicare Parts A and B. Your Medicare card will arrive about 3 months before your 65th birthday. You don't need to do anything — but you should still review your coverage options and decide if you want Medicare Advantage or Medigap.

Under 65 with Disabilities

If you're under 65 and receive Social Security Disability Insurance (SSDI), you're automatically enrolled in Medicare after 24 months of SSDI benefits. Your enrollment works the same way, and you have the same plan options.