Paying for healthcare is a challenge for retirees, and although Medicare provides a lot of help, the alphabet soup of Medicare coverage can take some effort to figure out. Medicare Part B is a crucial component of how retirees get the everyday healthcare that they need. To answer some of the questions that older Americans frequently have about the program, here are some of the key provisions of Medicare Part B and how you can use it to cover the expenses of doctor visits and other outpatient treatment needs.

How much does Medicare Part B cost?

Part B coverage for medical services requires Medicare participants to pay a monthly premium. For 2018, the premium that most participants will pay is $134 per month. About a quarter of Medicare beneficiaries will qualify to pay a lower amount due to unusually low cost-of-living increases in their Social Security payments over the past several years. The hold-harmless provision under Medicare and Social Security limits Medicare premium increases to the amount by which a participant's Social Security checks go up. Although most participants will have seen their monthly benefits catch up to Medicare premium increases by the time 2018 cost-of-living increases take effect in January, those who don't will get their Part B coverage at a discounted premium.

There is also a means test that requires some people to pay higher premiums for their Part B coverage. Depending on your income, premiums can be as much as $428.60 per month.

For individuals with this income:

Or joint filers with this income:

Total monthly premium in 2018 will be:

$85,000 to $107,000

$170,000 to $214,000

$187.50

$107,000 to $133,500

$214,000 to $267,000

$267.90

$133,500 to $160,000

$267,000 to $320,000

$348.30

Over $160,000

Over $320,000

$428.60

Data source: Medicare.

You'll also have to pay deductibles and coinsurance amounts in addition to premium payments. The deductible for Part B is $183 per year. You're responsible for paying that amount out of your own pocket before Medicare starts providing coverage, and after that, Medicare typically covers 80% of most services that Part B covers, leaving you with the remaining 20%. There are exceptions to this rule for certain preventive services for which Part B pays the entire amount.

What does Medicare Part B cover?

The key to Medicare Part B coverage is that any service or treatment must be medically necessary in order to treat a disease or medical condition. Services necessary to diagnose conditions are eligible, as are treatments to cure problems, prevent an illness from occurring in the first place, or detect early onset of a potential medical problem. The most common use of Medicare Part B among participants is to visit one's doctor. Medical diagnostic tests as part of one's ordinary treatment are also typical charges. Part B covers a wider range of items, ranging from ambulance services, clinical research, and durable medical equipment to mental-health services and second opinions for surgical operations.

Sheet with Medicare on it lying on a wood table with a stethoscope.

Image source: Getty Images.

When you first join Medicare, you can also take advantage of a one-time initial preventive visit. Referred to as a "Welcome to Medicare" visit, you'll get a doctor to review your medical history and assess key health characteristics such as height, weight, blood pressure, and a calculation of your body mass index. The visit also includes a vision test and an assessment of depression risk, and you'll receive a written plan from your doctor that tells you which screenings, shots, and other preventive services you'll need to get. After that, Medicare also provides yearly wellness visits to keep your vital information up to date.

Part B doesn't cover everything. In particular, Medicare won't pay the cost of dentures and most dental care, and you can't get coverage for eye examinations related to prescribing glasses or contact lenses. Hearing-aid examinations also typically aren't provided.

If you're ever confused about whether Medicare will cover a specific healthcare need, you can find out easily. A tool on the Medicare website will tell you whether a test, service, or medical device is included in coverage. You can also turn to your doctor or medical professional to find out whether Medicare will cover their recommended treatment.

Get the healthcare you need

Medicare Part B gives retirees the healthcare coverage they need, and a full range of necessary services is available to participants. These services, though, come at a cost, and it's crucial to understand exactly what you'll be on the hook to pay so that you don't get any nasty surprises in your retirement.

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