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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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
Special enrollment period
In most cases, you will be able to delay signing up for Part B beyond age 65 for as long as you have group health insurance from an employer for whom you or your spouse is still working.
When you (or your employed spouse) eventually stops working or your health coverage ends (whichever is earlier), you'll be entitled to a special enrollment period to sign up for Part B without penalty. This period lasts eight months from that date, but you can enroll earlier to ensure no break in coverage. Medicare benefits begin the first day of the month after you enroll.
Warning: If you have health coverage from an employer that has fewer than 20 workers, check with your plan to see if you're required to enroll in part B at 65.
Warning: To avoid a late penalty, you must enroll in Part B when employment ends — even if you continue to be covered under COBRA extended insurance or retiree health benefits.
Warning: Most people enroll in Part A during their initial enrollment period even if they delay Part B. But if you're still working and your employer coverage is a high-deductible plan with a health savings account, be careful. Under IRS rules, you cannot contribute to an HSA once you enroll in Medicare (A or B). The same is true if you are receiving Social Security retirement or disability benefits, because then you will be automatically enrolled in Part A as soon as you become eligible for Medicare. In these situations, you can continue to draw on funds already in your account, but you can't add to them. For details, see related article "Can I have Medicare as Well as a Health Savings Account?"
Other enrollment situations
If you qualify for Medicare through disability: Social Security will automatically sign you up for Parts A and B and mail your Medicare card to you shortly before your benefits become effective.
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.
If you're not a U.S. citizen: At or beyond age 65, you can apply for Medicare during a seven-month individual enrollment period that ends three months after the month in which you have both established legal residency and lived in the United States for five years.
If you have been married longer than one year to a U.S. citizen or legal resident who has worked and paid Medicare taxes for long enough, you may qualify for Medicare on your spouse's work record. See related article "Medicare Entitlement for Foreign Spouses."
- Enroll in Part B during your initial enrollment period (IEP) and pay monthly premiums — even though Medicare does not cover medical services overseas; or
- Delay Part B until your return to this country — but then you risk a permanent late penalty and may have to wait for coverage.
Except in very limited situations, medical coverage abroad does not entitle you to a special enrollment period when you return.
However, if you are working abroad — and covered either by a group health plan provided by your employer or by the national health program of the country you're living in — you will be entitled to the usual eight-month special enrollment period to sign up for Part B without penalty when you cease this employment or the health coverage ends, whichever happens first. Note that this right does not apply to people who are living overseas but not working.
If you are in prison when you turn 65: It's the same Catch-22. You are expected to enroll in Part B and pay premiums while incarcerated, even if you have no income, or face the same consequences as above on your release.
If you are in a domestic partnership: You're entitled to a special enrollment period if your coverage is from your own employer. But if you're covered under your partner's employer health insurance, you must enroll during your initial enrollment period at age 65 to avoid a late penalty. Medicare does not treat domestic partners the same way it treats legally married spouses.
Signing up for drug coverage
If you have drug coverage that is "creditable" — meaning that Medicare considers it of at least equal value to Part D — you don't need Part D when you turn 65. Your current insurance plan can tell you whether it's creditable or not.
If you lose creditable coverage — whether it's from a current or former employer, union, COBRA, the Department of Veterans Affairs (VA) or the military's TriCare-for-Life system — you'll have a two-month period to enroll in a Part D plan without penalty. But if you voluntarily drop such coverage after your individual enrollment period expired, you must wait until open enrollment at the end of the year.
You also get a special period to enroll in a Part D drug plan without penalty if you do so within two months of returning to the United States after living abroad.
Missing your enrollment deadline means:
- Being able to enroll in Part B only during the general enrollment period from Jan. 1 to March 31 each year, with coverage that doesn't begin until the following July 1.
- Paying a late penalty of an extra 10 percent permanently added to your Part B premiums for each 12-month period you delayed. For example, if you delayed five years, your premiums would cost 50 percent more for the same coverage for as long as you're in Medicare.
- Being able to enroll in Part D only during open enrollment from Oct. 15 to Dec. 7 each year, with coverage beginning Jan. 1.
- Paying a late penalty permanently added to your Part D premiums for every month that you did not have creditable drug coverage since turning 65.
Some exceptions: If you qualify for Extra Help under Part D or a Medicare Savings Program, you won't pay late penalties. If you have Medicare due to disability, any late penalty you incur will cease when you reach 65 and become entitled to Medicare based on your age.
How to enroll
To sign up for Part A or B, call Social Security at 1-800-772-1213 and make an appointment for an interview, which can be done on the phone or at your local Social Security office. If English is not your first language, you can request an interpreter at no charge.
To sign up for a Part D drug plan or Medicare Advantage plan, you must choose between the options available in your area. (See section "Figuring Out Your Choices.")
Next: What are your choices? »