En español | Q. My mother is an American citizen, age 85 and living abroad where she has free health care. She receives a Social Security check every month but never enrolled in Medicare, since it doesn't provide coverage overseas. She is thinking of returning to this country to live with me. How does she apply for Medicare after not taking it for so many years, and will she be penalized for waiting so long?

See also: Do veterans get special credit for Social Security?

A. The good news is that when your mother returns to the United States, she'll be entitled to Medicare Part A, which provides coverage for hospital stays. Because she gets a Social Security check, she should qualify for this hospital insurance, which has no monthly premium.

The bad news is that if she wants Medicare Part B insurance, which covers doctor bills, medical tests and medical equipment, she'll probably have to pay a hefty surcharge. Everyone pays for Part B, but her monthly premium will likely be 10 percent higher for each 12-month period in which she could have been enrolled in Part B but was not.

Man with stethoscope pressed to his chest. — Tetra Images/Getty Images

In 2011, the Part B premium for a person enrolling at 65 is $115.40 a month. Your mother will likely have to pay roughly 200 percent (10 percent a year x 20 years) on top of that — a total of $346.20.

Don't wait until she gets back — call Social Security at 1-800-772-1213 right away to ask about getting the ball rolling. But keep in mind that people in your mother's situation can enroll only during the annual general enrollment period, which runs from Jan. 1 to March 31 each year, with coverage not beginning until the following July.

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