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Medicare is a key program for millions of older and disabled Americans, but many don't really understand how Medicare works because they lack accurate information. Medicare is a complex program, but the following key elements are things you need to know right from the start:

  • Do give yourself time to bone up about Medicare. It's a system with many choices and deadlines. Being informed is the best way to side-step pitfalls and avoid mistakes that cost money.

  • Don't expect to be notified when it's time to sign up. Unless you're already receiving Social Security retirement or disability benefits, you must apply for Medicare. But you won't get any official notice on when or how to enroll.

  • Do enroll when you're supposed to. To avoid permanent late penalties, and maybe a delay in coverage, you need to know your personal deadline for enrolling in Medicare. It's either during your initial enrollment period around age 65 or during a special enrollment period if you continue to have health insurance after age 65 from an employer for whom you or your spouse is still working.

  • Don't despair if you haven't "worked long enough" to qualify. You may qualify for Medicare Part A (hospital insurance), without paying premiums for it, on your current or former spouse's work record. Or you may be able to buy into Part A by paying premiums. But you can get Part B benefits (coverage for doctors' services, outpatient care, and medical equipment) and Part D (prescription drug coverage) regardless of how long you worked (or even if you never have), just by paying the required premiums — provided that you're a U.S. citizen or a legal permanent resident (green card holder) who's lived in the United States for at least five years before applying for Medicare.

  • Do find out how other health insurance works with Medicare. Being eligible for Medicare can affect other insurance you have (such as benefits from a current or former employer or union) in significant ways.

  • Don't worry that poor health will affect your coverage. If you qualify for Medicare, you receive full benefits. You can't be denied coverage or asked to pay higher costs because of current or past health problems.

  • Do remember that Medicare isn't free. You pay premiums for coverage and co-payments for most services unless you qualify for a low-income program or have extra insurance from another source.

  • Don't assume that Medicare covers everything. It covers a wide range of medical services (including expensive ones like organ transplants), prescription drugs, and medical equipment. But there are gaps, such as coverage for routine vision, hearing, and dental care. And Medicare doesn't cover the non-medical costs of long-term care in nursing homes and assisted living facilities.

  • Don't expect Medicare to cover your dependents. Nobody can get Medicare under age 65, except those who qualify through disability. Medicare has no family coverage.

  • Do get help if you need it. You may qualify for low-income programs that cover your premiums or provide low-cost prescription drug coverage. Whatever your income, you can also get free personal help — in English or another language — to sort through your options in Medicare and choose the one that best suits your needs.