Your Medicare Initial Enrollment Period, month by month
When your seven-month Initial Enrollment Period starts and ends, when coverage begins depending on when you sign up, and what to do at each step.
You become eligible for Medicare in the month you turn 65. Your Initial Enrollment Period (IEP) is seven months long: the three months before your birthday month, the birthday month itself, and the three months after.
When coverage starts
| You sign up in | Part B coverage starts |
|---|---|
| Any of the 3 months before your birthday month | The first day of your birthday month |
| Your birthday month | The first day of the next month |
| Any of the 3 months after | The first day of the month after you sign up |
If your birthday is on the first of the month, everything shifts one month earlier.
Automatic enrollment
If you already receive Social Security retirement benefits, you are enrolled in Parts A and B automatically and your card arrives about three months before 65. If you do not, you must sign up through Social Security online, by phone, or at an office.
A practical timeline
- About 6 months before 65: review your current coverage, drug list and doctors. If you or your spouse are still working, find out whether employer coverage counts as creditable (see working past 65).
- 3 months before: apply for Part A and Part B if you need to.
- 2 months before: choose between Medigap with a Part D plan, or Medicare Advantage. Compare 2026 costs in Medicare costs at a glance.
- Birthday month: coverage starts; your Medigap open enrollment begins once you are 65 and in Part B.
- After: keep your Medicare card, Part D card and supplement card together.
Why the deadline matters
Missing your IEP without other qualifying coverage can mean a lifetime Part B penalty and a gap before the next General Enrollment Period. The penalty maths shows how quickly it adds up.
Getting help
Free counselling is available through your state's SHIP (SHIBA in Washington, SHINE in Florida). For a quote on supplement plans in Washington or Florida, Maru Insurance is an independent agency licensed in both states.
Questions people ask
How long is the Initial Enrollment Period?
Seven months: three before your 65th birthday month, the month itself, and three after.
Am I enrolled automatically?
Yes, if you already receive Social Security benefits. Otherwise you must apply.
When does coverage start if I enroll early?
On the first day of your birthday month.
Can I delay Part B?
Yes, without penalty, if you have creditable employer coverage from current work.
Independent educational site. Not affiliated with or endorsed by the U.S. government, the federal Medicare program, or any insurance company. Figures are 2026 amounts published by CMS unless noted; check Medicare.gov for your situation.