When should I sign up for Medicare?

Your Medicare Initial Enrollment Period, explained

Most people first become eligible for Medicare at 65. Your first chance to sign up is called the Initial Enrollment Period. It lasts 7 months: the 3 months before the month you turn 65, your birthday month, and the 3 months after.

Signing up during the first 3 months is best, because your coverage starts on the first day of your birthday month with no gap. If you sign up during your birthday month or later, coverage starts the first day of the following month.

The parts of Medicare

• Part A (hospital insurance) covers hospital stays, skilled nursing after a hospital stay, and hospice. Most people pay no premium because they or a spouse paid Medicare taxes for at least 10 years.
• Part B (medical insurance) covers doctor visits, outpatient care, tests, and medical equipment. It has a monthly premium that changes each year, and it costs more for people with higher incomes.
• Part D (drug coverage) is offered by private insurers approved by Medicare.
• Medicare Advantage (Part C) is an all-in-one alternative from private insurers that replaces Original Medicare (Parts A and B) and often includes drug coverage.
• Medigap (Medicare Supplement) policies help pay the costs Original Medicare doesn't cover, like deductibles and coinsurance.

Do I have to sign up, or is it automatic?

If you're already getting Social Security or Railroad Retirement benefits at least 4 months before you turn 65, you're usually enrolled in Part A and Part B automatically, and your card comes in the mail. Otherwise you need to sign up yourself through Social Security, online, by phone, or at a local office.

Working past 65

If you or your spouse are still working and covered by that employer's group health plan, you may be able to delay Part B without a penalty. This usually applies when the employer has 20 or more employees, because the job-based plan then pays first. When the job or the coverage ends, you get an 8-month Special Enrollment Period to sign up.

Be careful: COBRA and retiree health plans do not count as coverage from current work. If you rely on them instead of signing up for Part B, you can face a gap in coverage and a lifelong penalty. Check with your employer's benefits office before you decide.

How the late penalties work

• Part B: 10% added to your premium for each full 12-month period you could have had Part B but didn't, usually for as long as you have Part B.
• Part D: a penalty added to your drug plan premium for each month you went without drug coverage that was at least as good as Medicare's (called "creditable coverage"), for as long as you have Part D.
• Part A: only applies if you have to pay a premium for Part A. Most people don't.

Common questions