Turning 65: Your Medicare Checklist

You have a 7-month window to get Medicare right. Here is the month-by-month timeline, the decisions that matter, and the penalties to avoid.

When is your enrollment window?

Pick the month and year you turn 65 to see your dates.

Your Initial Enrollment Period starts three months before the month you turn 65 and ends three months after it. Sign up in the three months before your birthday month and coverage starts the first day of your birthday month. Sign up later in the window and coverage starts the first day of the month after you sign up. If your birthday is on the 1st, each date moves one month earlier.

Your 7-month enrollment window

The window starts three months before the month you turn 65 and ends three months after it. When you enroll inside the window changes when coverage starts.

  1. 3 months before your birthday month: Your Initial Enrollment Period opens. Enrolling now is the only way to have coverage effective on the first day of your birthday month.
  2. 2 months before: Gather your prescription list, your doctors, and your preferred pharmacy. Ask your employer's HR whether your current coverage is creditable.
  3. 1 month before: Compare Medicare Advantage against Medicare Supplement plus a Part D plan. Verify your providers in each plan's directory.
  4. Your birthday month: Enrolling during this month delays your start date. Coverage begins the first of the following month.
  5. 1 to 3 months after: Your window is still open, but coverage starts later and gaps can appear. Enroll before it closes to avoid a penalty.

The three decisions you actually make

  • 1. Do you take Part B now? Yes for most people. Delay only if you have qualifying employer coverage that lets you enroll later without a penalty.
  • 2. Medicare Advantage or Medicare Supplement? Lower premiums with a network and copays, or higher premiums with predictable costs and any provider that accepts Medicare. See the full comparison.
  • 3. How do you cover prescriptions? Built into most Advantage plans, or a standalone Part D plan alongside a Supplement.

What to have ready

Late enrollment penalties for Part B and Part D are permanent. If you plan to delay because you are still working, get your employer coverage confirmed as creditable in writing first. See how penalties are calculated.

  • Your Medicare number, once you have it from Social Security
  • A complete list of prescriptions with dosages
  • The doctors and specialists you want to keep
  • Your preferred pharmacy
  • Whether you have employer, retiree, VA, or TRICARE coverage
  • A rough monthly budget for premiums

Frequently asked questions

Am I enrolled in Medicare automatically at 65?

Only if you are already receiving Social Security or Railroad Retirement benefits. Otherwise you must actively enroll through Social Security. Advantage, Supplement, and Part D coverage always requires a separate enrollment.

What happens if I miss my Initial Enrollment Period?

Unless you qualify for a Special Enrollment Period, you may have to wait for the General Enrollment Period and pay a late enrollment penalty for Part B, Part D, or both. Part B and Part D penalties last as long as you have that coverage.

Can I keep my employer plan and skip Medicare?

Sometimes. If your employer has 20 or more employees and the coverage is creditable, you can usually delay Part B and Part D without a penalty. Smaller employers, retiree plans, and COBRA follow different rules, so confirm before you delay.

Do I need Part D if I don't take any medications?

Usually yes. Without creditable drug coverage, the Part D late enrollment penalty accrues for every month you go without it and is added to your premium permanently once you do enroll.

When is the best time to start comparing plans?

About three to four months before your birthday month. That gives you time to check networks, price your prescriptions, and enroll for a start date with no gap.