What does Medicare cover? Not knowing could mean financial disaster. Planning ahead, though, could help many Americans avoid missing out on services they may take for granted before retirement. Here's how to navigate and get the most out of it.
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This Is What Medicare Does And Doesn’t Cover | CNBC

It's basically a rite of passage: You blow out the candles on your 65th birthday and get to sign up for Medicare.

Yet it's kind of like one of those birthday gifts that you have to assemble properly for it to work well.

In other words, if you enroll in Medicare without exploring the details of your medical coverage and weighing your options, you could end up on the hook for health care costs that you did not anticipate.

Every day, about 10,000 baby boomers reach age 65 and can join the 49 million or so other older Americans enrolled in Medicare. (The government program also provides coverage to about 9 million younger people with permanent disabilities.)

Like Social Security, it's a benefit that you've been funding for years as a working taxpayer.

And as long as your work history (or your spouse's) spans at least 10 years, you'll pay nothing for Medicare's Part A (hospital coverage) and an income-based amount for Part B (doctor's visits).

You should make sure to sign up during your initial enrollment window, which opens three months before your birthday month and ends three months after it.

If you sign up after that, you could end up paying late-enrollment penalties unless you meet an exclusion (i.e., you still have health insurance through work).

Yet even for those who sign up as soon as they can, unanticipated costs and coverage gaps can catch them flat-footed.