Turning 65 Medicare Checklist: The Step-by-Step Timeline for Adult Children

Your parent is turning 65, and somewhere between the birthday card and the cake, you've realized that you're the one who's going to have to figure out Medicare. Your parent received a stack of mail from insurance companies. They're confused. You're confused. And the government's enrollment window does not care that you're busy.

This checklist breaks the process into concrete steps, organized by when to do them relative to your parent's 65th birthday. If you follow this timeline, your parent will be enrolled correctly, on time, and without the lifetime penalties that catch thousands of families every year.

12 months before: start learning

The year before your parent turns 65 is for education, not enrollment. You cannot enroll yet, but you can -- and should -- start understanding the system.

• [ ] Read the basics. Understand what Medicare Parts A, B, C, and D cover and how they work together
• [ ] Determine if your parent will still be working. If your parent (or their spouse) has employer health coverage through a company with 20+ employees, they may be able to delay Part B without penalty. If the employer has fewer than 20 employees, Medicare becomes primary, and delaying Part B is risky
• [ ] Make a list of your parent's current doctors, specialists, and medications. You will need this when comparing plans
• [ ] Check whether your parent gets Social Security. If they're already receiving Social Security benefits, they will be automatically enrolled in Parts A and B. If they are not receiving Social Security (because they delayed benefits), they will need to enroll manually

6 months before: the mail starts

Around six months before your parent's 65th birthday, the insurance industry will find them. Expect:

• A flood of mailers from Medicare Advantage companies
• Phone calls from insurance agents and brokers
• The official "Medicare & You" handbook from CMS

Here's what to do:

• [ ] Do not let your parent sign anything from the mailers. These are marketing materials, not enrollment forms. Many families accidentally enroll in a Medicare Advantage plan they did not intend to choose because a mailer looked official
• [ ] Set up a folder (physical or digital) for all Medicare-related documents. You will need to reference them during enrollment
• [ ] Contact Social Security (ssa.gov or 1-800-772-1213) if your parent is not already receiving Social Security benefits. They will need to actively apply for Medicare

3 months before: the enrollment window opens

Your parent's Initial Enrollment Period (IEP) is a 7-month window: it starts 3 months before their birthday month, includes their birthday month, and extends 3 months after. This is when the real decisions happen.

• [ ] Enroll in Part A. This is almost always free. There is no reason to delay Part A unless your parent has a Health Savings Account (HSA) -- enrolling in Part A requires them to stop contributing to the HSA
• [ ] Decide on Part B. If your parent is retiring and will not have employer coverage, enroll in Part B. If they are still working with employer coverage from a company with 20+ employees, they can generally delay Part B without penalty
• [ ] Choose a path: Original Medicare + Medigap + Part D, or Medicare Advantage. This is the biggest decision. Read the Medigap vs. Medicare Advantage comparison and the Plan G vs. Plan N breakdown to understand the options
• [ ] If choosing Medigap: Apply for a Medigap policy during the 6-month Medigap Open Enrollment Period, which starts the month Part B becomes effective. During this window, insurance companies cannot deny coverage or charge more due to pre-existing conditions. This is a one-time right -- miss it, and your parent may face medical underwriting later
• [ ] If choosing Medicare Advantage: Compare plans at Medicare.gov/plan-compare using your parent's zip code, doctors, and medications
• [ ] Enroll in Part D (if going the Original Medicare + Medigap route). Your parent needs a standalone prescription drug plan. Use Medicare.gov/plan-compare to find plans that cover their specific medications at the lowest cost

Enrollment timing matters

When you enroll during the IEP determines when coverage starts:

Enrolling early in the IEP means coverage starts sooner. There is no advantage to waiting.

The birthday month: verify everything

• [ ] Confirm enrollment. Log in to Medicare.gov or call 1-800-MEDICARE (1-800-633-4227) to verify that Parts A and B are active
• [ ] Check the Medicare card. Your parent should receive their red, white, and blue Medicare card in the mail. It lists their Medicare number and the effective dates for Part A and Part B
• [ ] Verify Medigap or Advantage enrollment with the insurance company directly. Confirm the plan is active and matches what was selected
• [ ] Set up a MyMedicare.gov account for your parent so they can view claims and coverage details online

3 months after: final deadline

The IEP closes 3 months after your parent's birthday month. If they have not enrolled in Part B by this point and do not have qualifying employer coverage, they will face a late enrollment penalty -- a 10% surcharge on Part B premiums for every 12-month period they could have enrolled but didn't. That penalty lasts for the rest of their life.

• [ ] Confirm all enrollment is complete before the IEP closes
• [ ] If your parent delayed Part B due to employer coverage: Keep records. They will need proof of continuous employer coverage when they eventually enroll using a Special Enrollment Period. The employer's HR department should provide a CMS-L564 form (Request for Employment Information)

If your parent is still working past 65

This scenario is increasingly common and creates the most confusion. Here are the rules:

Employer with 20+ employees: Employer coverage is primary. Medicare is secondary. Your parent can delay Part B without penalty as long as they have coverage through the employer (or their spouse's employer). When they retire or lose employer coverage, they get an 8-month Special Enrollment Period to sign up for Part B.

Employer with fewer than 20 employees: Medicare is primary. The employer plan is secondary. Your parent should enroll in Part B at 65 even if they have employer coverage, because Medicare is expected to pay first.

Self-employed or no employer coverage: Enroll in Part B during the IEP. There is no exception for self-employment.

COBRA: COBRA coverage does not count as employer coverage for Medicare purposes. If your parent is on COBRA and turns 65, they should enroll in Part B immediately. This is one of the most common and expensive mistakes families make.

The annual review: every October

Medicare enrollment is not a one-time event. Every year during the Annual Enrollment Period (October 15 through December 7), your parent should review their coverage:

• [ ] Check whether their medications are still on the plan's formulary
• [ ] Verify that their doctors are still in-network (for Advantage plans)
• [ ] Compare costs with other available plans using Medicare.gov/plan-compare
• [ ] Consider whether their health or circumstances have changed enough to switch between Original Medicare and Medicare Advantage

Plans change their formularies, premiums, and networks annually. A plan that was excellent in 2025 might drop your parent's cardiologist or move their blood pressure medication to a higher cost tier in 2026.

Documents your parent should have on file

Keep these organized and accessible:

• [ ] Medicare card (red, white, and blue)
• [ ] Medigap or Medicare Advantage plan ID card
• [ ] Part D plan ID card (if standalone)
• [ ] Social Security statement
• [ ] CMS-L564 form (if delaying Part B due to employer coverage)
• [ ] List of current medications with dosages
• [ ] List of current doctors with contact information and NPI numbers
• [ ] Copy of any Authorized Representative form (CMS-10106) if you're managing their Medicare on their behalf

This checklist covers the essentials, but every family's situation has wrinkles -- employer coverage, HSA accounts, COBRA, dual eligibility, or helping a parent who lives in a different state. For a comprehensive printable version of this timeline, plus comparison worksheets and a penalty calculator, the Medicare Enrollment Guide walks through every scenario for $14.