Medicare covers tens of millions of Americans, providing much-needed support for healthcare expenses. If you're about to turn 65, then you're probably becoming eligible for Medicare for the first time. Here's what you need to know about your Medicare coverage so that you can take full advantage of your benefits once your coverage starts.

What do I need to do to sign up for Medicare?

The process of signing up for Medicare is different depending on your particular circumstances. If you've already started getting Social Security benefits, you'll typically be enrolled automatically in Medicare when you turn 65. If not, you'll have to go to the Social Security Administration website, which handles registration both for Medicare and Social Security.

You'll have the choice of enrolling for Medicare and Social Security at the same time, or enrolling only for Medicare. By visiting the SSA website, you can find out what forms you'll need to complete and what information you'll have to provide to get your benefits started on time.

Medicare notebook with stethoscope.

Image source: Getty Images.

What Medicare benefits can I get?

Medicare comes in four different parts, lettered A, B, C, and D. Each part of Medicare covers a different type of healthcare expense:

  • Part A is for inpatient care like hospital stays, skilled nursing facilities, or hospice coverage.
  • Part B covers outpatient expenses like doctor visits, routine physicals, and procedures that don't require an inpatient hospital stay.
  • Part C is reserved for Medicare Advantage plans, which are a private-insurance alternative to traditional Medicare. These plans often offer combined coverage of what traditional Medicare covers in Parts A, B, and D.
  • Part D covers prescription drug costs.

When you sign up for Medicare, you'll need to make some coverage choices. Part A comes at no cost as long as you or your spouse has worked 10 years or more in a job that involved paying Medicare payroll taxes. Part B and D coverage comes with monthly premiums, and you'll have to pick a specific Part D plan. Medicare Advantage plans also require premium payments, and costs can differ among providers, so it pays to do some comparison shopping.

How does Medicare work with other insurance?

Some 65-year-olds still have private coverage, either through their own employer or through their spouse's group coverage. In that case, rules differ about whether Medicare or your private insurance will be primarily responsible for healthcare costs.

If your group health coverage is from a large employer with 100 or more employees, then the group health plan is the primary coverage provider. Medicare will play only a secondary role in providing coverage. By contrast, if you work for an employer with fewer than 20 employees, then Medicare becomes the primary provider of coverage, leaving your group health plan to provide secondary coverage. For employers with between 20 and 99 employees, the question is whether the health plan qualifies as a large group health plan or not. If it does, then the plan must provide primary coverage, while small health plans are secondary to Medicare.

Different rules apply to special circumstances, such as those covered by the federal government's TRICARE plan for military personnel. Be sure to check with your employer to see how Medicare will affect your benefits. In some cases, group health plans will insist on your signing up for Medicare in order to defray what the plan would otherwise have to pay out of its own pocket.

Am I stuck with my initial choice of Medicare coverage?

Choosing a Medicare option is a major decision, but it doesn't lock you in to your choice forever. Medicare offers an open enrollment period each year that lets you change your coverage. You can move from traditional Medicare to a Medicare Advantage plan, from Medicare Advantage back to traditional Medicare, or from one Medicare Advantage plan to another. You can also use open enrollment to switch between prescription drug plans. Other periods allow you to make specific types of changes, and special enrollment periods apply when you lose coverage from another source, such as a group health plan.

Medicare is a benefit that most Americans earn, and you should take advantage of the coverage it provides. Knowing more about Medicare will make it easier to claim your benefits and use them effectively when the time comes.

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