Enrolling at the Right Time

Meet your enrollment deadline to avoid consequences

by: Patricia Barry, from: AARP Bulletin, Updated May 7, 2012

En español | Nobody is obliged to sign up for Medicare. But there are important consequences if you don't meet your enrollment deadline and then decide to join the program later. As many have learned the hard way — better to sign up at the right time than regret it later. Your own deadline depends on which enrollment period fits your circumstances:

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Medicare Starter Kit

What you need to know about Medicare when you’re new to the program. — Illustration by R.O. Blechman

Initial enrollment period

Anyone who is a U.S. citizen or legal resident and is turning 65 is entitled to an initial enrollment period that lasts seven months — from three months before the month of their 65th birthday to three months after that month. For example, if you turn 65 in June, your enrollment period is March 1 to Sept. 30.

Use this enrollment period to sign up for Medicare Part A and Part B at age 65 if:

you are retired or not working; or
you do not have health insurance from an employer for whom you or your spouse is still working; or
you live outside the United States and its territories.

Warning: To avoid a late penalty, enroll in Part B at age 65 even if you haven't worked long enough to get Part A without paying a premium.

If you are already receiving Social Security retirement benefits when you turn 65, you need not apply for Medicare. Your Medicare card will be mailed to you, and coverage begins the first day of your birthday month. You can decline Part B if you choose — for example, if you are covered by health insurance provided by your own or your spouse's current employment — by following the instructions on the letter Social Security sends you.

Unless you're already receiving Social Security benefits, you need to apply for Medicare if you want it. Your coverage begins according to which month of your seven-month initial enrollment period you sign up:

Months 1, 2 and 3: the first day of the month in which you turn 65
Month 4: one month after enrolling
Month 5: two months after enrolling
Months 6 or 7: three months after enrolling

Next: What's the special enrollment period? »