Your Initial Enrollment Period
The Initial Enrollment Period lasts seven months: the three months before your 65th birthday month, your birthday month, and the three months after.
When your coverage starts depends on when you sign up. Sign up before your birthday month and coverage starts the first day of your birthday month. Sign up during your birthday month or later in the window, and coverage starts the first day of the next month.
If you already get Social Security benefits at least four months before you turn 65, you are enrolled in Part A and Part B automatically. Your card arrives in the mail about three months before your birthday.
Still working at 65?
If you have health coverage through your own or your spouse's current job, you may be able to delay Part B without a penalty. The rules depend on employer size:
- 20 or more employees: your group plan pays first, and you can usually delay Part B. When the job or coverage ends, you get an eight-month Special Enrollment Period to sign up.
- Fewer than 20 employees: Medicare usually pays first, so you likely need Part B at 65.
Two traps to watch. COBRA and retiree coverage do not count as current employment coverage for delaying Part B. And if you contribute to a Health Savings Account, stop contributions before Medicare starts, since Part A can backdate up to six months.
The big decision: how to fill the gaps
Original Medicare covers a lot but leaves you with deductibles, 20% coinsurance and no yearly cap. Most people pick one of two paths:
- Original Medicare plus a Medigap plan and a Part D plan. Higher premiums, low surprise costs, any doctor that takes Medicare.
- A Medicare Advantage plan. Lower premiums, a yearly cost cap, and a local network.
Your six-month Medigap Open Enrollment Period starts when you are 65 and enrolled in Part B. It is the only time most states guarantee you can buy a Medigap plan without health questions, so make this choice with care.