# When do you sign up for Medicare at 65? The seven-month window, month by month

- URL: https://www.agentskillpacks.com/guides/medicare-sign-up-window-at-65
- Updated: 2026-10-21
- Book: The Year You Turn 65 by Nancy Whitaker (https://www.agentskillpacks.com/books/the-year-you-turn-65)

## Short answer

Your Medicare sign-up window is seven months long. It opens three months before the month you turn 65, includes your birthday month, and closes three months after it. Medicare calls it the Initial Enrollment Period. If you sign up in the first three months, Part B starts in your birthday month. If you sign up in your birthday month or later, Part B starts the month after you apply. That shorter wait is a rule from January 1, 2023. If your birthday is on the 1st, the whole window moves one month earlier.

**When Part B starts, by the month you sign up (rule in effect since January 1, 2023)**

| If you sign up | Part B starts |
| --- | --- |
| In month 1, 2 or 3 of the window (the 3 months before your birthday month) | The first day of your birthday month |
| In your birthday month (month 4) | The first day of the next month |
| In month 5, 6 or 7 (the 3 months after your birthday month) | The first day of the month after you sign up |
| After the window closes, with no other way in | General Enrollment Period, January 1 to March 31. Coverage starts the month after you sign up |

## How to read the seven months in the table

Start with one date: the month you turn 65. Count back three months. That is when your window opens. Count forward three months. That is when it closes.

Seven months in all. Medicare calls it the Initial Enrollment Period. For most people it comes once.

The table shows what each part of the window does to your Part B start date. Part B covers doctors and outpatient care. Part A, the hospital part, starts in your birthday month either way if you get it with no premium.

Coverage always starts on the first of a month. So "the month after" means the 1st of the next month.

Here is a quick example. Say you turn 65 in August. Your window opens in May and closes in November. Sign up in June and Part B starts August 1. Sign up in September and it starts October 1.

## The two-month wait your neighbor still talks about

Until 2023, a late sign-up inside the window could mean waiting two or three months for Part B. Plenty of people still repeat that rule. It changed.

A 2021 law, the Consolidated Appropriations Act, rewrote it. The federal rule took effect January 1, 2023. That rule gave its own before-and-after cases. Sign up in May: the old rule started you July 1, the new one starts you June 1. Sign up in July: October 1 under the old rule, August 1 now. The [CMS page on Part A and B sign-up](https://www.cms.gov/medicare/enrollment-renewal/original-part-a-b) has the current dates.

So if a friend, a website or an older book tells you about a long wait, check the date it was written. The old rule is still everywhere, so we flag it here.

## Do you even have to sign up yourself?

This is the question most people skip. Look at your bank statement. Is a Social Security payment arriving each month?

If those payments started at least 4 months before you turn 65, Medicare signs you up for Part A and Part B on its own. The card comes by mail about 3 months before coverage starts.

If not, the window is yours to track. Nothing arrives. You go to Social Security, online at SSA.gov/medicare/sign-up or by appointment.

Two exceptions. In Puerto Rico you get Part A on its own but must sign up for Part B. If you live outside the United States, you are not signed up for Part B on its own either.

And one more thing for the 1st-of-the-month birthdays. Social Security treats you as turning 65 a month early. Its own manual says people born on the 1st are "ordinarily unaware" of this. Shift every date one month back.

## Medicare at 65 is not Social Security at 65

Many people mix up these two dates. Medicare starts at 65. Social Security's full retirement age, the age that pays your full benefit, depends on the year you were born.

| Year of birth  | Full retirement age                                         |
| -------------- | ----------------------------------------------------------- |
| 1943 to 1954   | 66                                                          |
| 1955 to 1959   | 66 and 2 months, rising 2 months a year to 66 and 10 months |
| 1960 and later | 67                                                          |

If you turn 65 in 2026 or 2027, you were born in 1961 or 1962, so your full retirement age is 67.

The book's point is that the two clocks run apart. Your Social Security start date does not move your Medicare window. The seven months open and close around your 65th birthday either way. The one link is this: if your Social Security started at least 4 months before 65, Medicare signs you up on its own.

## If you still have coverage from a job

The seven months are not the only way in for everyone. If you or your spouse still work and have health coverage from that job, you may be able to put off Part B without a penalty.

The size of the employer matters. With 20 or more employees, the job's plan pays first. With fewer than 20, Medicare pays first, and the job's plan might not pay for care if you lack Part A and Part B. Ask your benefits office in writing. Our page on [still working at 65](/guides/still-working-at-65-delay-medicare-part-b) has the full rule and the 8-month window that opens when the job ends.

## It is a Sunday night and the birthday is ten months away

You are paying bills at the kitchen table. A Medicare ad comes on TV, the third one this week. You realize you do not know a single date.

You search. One page says sign up three months before. Another says you have until your birthday. A friend says she waited two months for her card. All three sound sure.

Here is what is true. There is one window, it is seven months long, and it is built around your birthday whether you are ready or not. Once you write the three dates down, the noise gets quieter. The [official page on when you can sign up](https://www.medicare.gov/basics/get-started-with-medicare/sign-up/when-can-i-sign-up-for-medicare) says the same thing, in more words.

Whatever way you sign up, keep proof of the date. Save the online confirmation. If you call, write down the name of the person you spoke with. If a question about your start date ever comes up, that is what you will need.

## What the book adds to these dates

This is the problem [The Year You Turn 65](/books/the-year-you-turn-65) was written for. Nancy Whitaker's book is built on a calendar, not on topics, and the window is its spine.

**How to Use This Book** opens with a fill-in box. You write your birthday month, then the month three before and the month three after. Every later chapter counts from those dates.

**Twelve Months Out: Find Out Which Kind of 65 You Are** sorts out whether Medicare will sign you up or you have to do it, and which of four coverage paths you are on.

**Three Months Out: The Seven-Month Window Opens** is the working page for the window itself. It has the start-date table, the 2023 change with its examples, the 1st-of-the-month rule and what the late penalty adds in 2026 dollars.

The book is not affiliated with Medicare or Social Security, and it does not pick a plan for you. For your own file, your State Health Insurance Assistance Program (SHIP) gives free counseling, and Social Security can confirm your dates. Ask them for the date in writing.

## Where this is in the book

- How to Use This Book
- Twelve Months Out: Find Out Which Kind of 65 You Are
- Three Months Out: The Seven-Month Window Opens

Kindle: https://www.amazon.com/dp/B0HLB95HY6
Paperback: https://www.amazon.com/dp/B0HLBWL7D4

Links go to Amazon. ToolGenX publishes this book under a pen name and earns from every sale.

Not affiliated with Medicare, the Social Security Administration, or any government agency. This book lays out published rules and dates. It is not legal, tax, medical or financial advice. For your own record, call your State Health Insurance Assistance Program (SHIP) or Social Security.

## Is the book for you?

- Yes, if You turn 65 within the next year and nobody has told you a date
- Yes, if You are not getting Social Security yet, so Medicare will not sign you up on its own
- Yes, if You heard a rule about long waits and want to know if it is still true
- Skip it if You want someone to tell you whether to take Part B now or later
- Skip it if You are already past your window and need a fix today (start with the penalty page instead)

## FAQ

### How early can you sign up for Medicare before turning 65?

Three months before the month you turn 65. That is when your seven-month window opens. Medicare's handbook also says you can contact Social Security 3 months before you turn 65 to set up an appointment.

### When does Medicare Part B start if I sign up in my birthday month?

The first day of the month after you sign up. Under the rule in place since January 1, 2023, a sign-up in your birthday month or in the 3 months after starts coverage the next month.

### What if my birthday is on the 1st of the month?

Social Security treats you as reaching 65 in the month before. Your whole window opens one month sooner and closes one month sooner. Use the shifted dates, because those are the ones Social Security uses.

### What happens if I miss my Medicare sign-up window?

If you have no other way in, your next chance is the General Enrollment Period, January 1 to March 31 each year. Coverage starts the month after you sign up. A late Part B premium penalty may also apply, unless you had the right kind of job coverage in the meantime.

### Where do you sign up for Medicare Part A and Part B?

Through Social Security, online at SSA.gov/medicare/sign-up or by appointment. If you worked for a railroad, you sign up through the Railroad Retirement Board at RRB.gov instead.

### Do I have to sign up for Medicare at 65 if I am still working?

Not always. If you have health coverage from your own or your spouse's current job, you may be able to put off Part B and sign up later in an 8-month window with no late penalty. At an employer with fewer than 20 employees, Medicare pays first, and most of those plans expect you to sign up at 65. COBRA and retiree plans do not count. Ask your benefits office in writing.