Not everyone is automatically enrolled for Medicare coverage Kiplinger's Personal Finance: What you need to know about signing up for Medicare

Kiplinger's Personal Finance

When you turn 65, you have to master a new health care system. We have answers to some of your most frequently asked questions about Medicare enrollment.

QUESTION: Do I need to sign up for Medicare, or will I be enrolled automatically?

ANSWER: If you signed up for Social Security before age 65 (eligibility for full benefits currently begins at age 66), you will automatically be enrolled in Medicare parts A and B and receive your card three months before your 65th birthday.

Part A covers hospitalization and is generally premium-free; Part B covers outpatient care, such as doctors' visits, X-rays and tests, and costs $134 a month for people who enroll in 2017 (or more for high earners).

Everyone else needs to take steps to enroll - or face a lifetime late-enrollment penalty (unless you're still working and have employer coverage). Go to www.socialsecurity.gov to sign up anytime from three months before until three months after you turn 65 (your "initial enrollment period"), even if you are waiting to file for Social Security benefits.

QUESTION: I'm still working. Do I need to sign up?

ANSWER: That depends on the size of your company. If you or your spouse (if you're covered by your spouse's insurance) is still working for a firm with 20 or more employees, the employer's insurance is your primary coverage, and Medicare is secondary and can fill any gaps in coverage.

You aren't required to sign up for Medicare at 65, and you won't have a late-enrollment penalty as long as you sign up within eight months of leaving your job and losing work-based coverage.

But the rules are different if you work for a company with fewer than 20 employees. In that case, Medicare generally becomes your primary coverage at age 65, and you need to sign up for Part A and Part B while you're still working.

Also note that you can't delay signing up for Part A if you're already receiving Social Security benefits and were automatically enrolled in Medicare - even if you're still working.

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