Medicare 101: Do You Need All 4 Medicare Parts?

There are four parts of Medicare: Part A, Part B, Part C, and Part D. In general, the four Medicare parts cover different services, so it's essential that you understand the options so you can pick your Medicare coverage carefully.

Maybe you're getting close to the age of 65 or simply want to understand how Medicare works so you can help a family member or friend. While some people who sign up for Medicare are retired, others are still working. Whatever your situation, you become eligible for Medicare when you reach 65. In fact, if you are already receiving Social Security, you'll be enrolled in Medicare automatically the month you turn 65. The card will arrive in the mail.

In addition, you are automatically enrolled in Medicare Parts A and B if you are disabled and have received disability payments from Social Security for 24 months.

Medicare has evolved over the years and now has four parts. While some are mandatory, others are optional.

Medicare Part A: Hospital Insurance

Medicare Part A covers the costs of hospitalization. This includes inpatient care at a hospital, skilled nursing facilities, hospice care, and home health care. For most people, there is no monthly cost for Part A if you or your spouse paid Medicare taxes for at least 10 years. If you didn’t pay enough into Medicare, the premium for Part A is either $278 or $505 per month.

In 2024, a $1,632 deductible applies before Part A begins to cover hospitalization costs. At that point, you pay $0 for the first 60 days of coverage. Co-payments apply for stays beyond 60 days and you pay for the entirety of your hospital stay after 150 days.

Although Medicare Part A covers hospice care at an inpatient facility, it must be arranged through a Medicare-approved hospice provider.

Medicare Part B: Doctors and Tests

Medicare Part B covers visits to the doctor. This includes lab tests, home health care services, medical equipment, services a doctor provides while you’re a hospital inpatient, outpatient mental health care, and other outpatient services. Cardiac rehabilitation, mammograms, cardiovascular screenings, diabetes screenings, flu shots and a host of other preventive services are also covered by Part B.

You pay a monthly premium for Medicare Part B, which is based on your annual income. A single person who earned $103,000 or less (or a married couple earning $206,000 or less) would pay $174.70 per month in 2024. This amount is deducted from your Social Security benefit.

You're not required to enroll in Part B if you have creditable coverage from another source, such as an employer or spouse's employer. If you don't enroll and you don't have creditable coverage from another source, you may have to pay a penalty if you enroll later.

Medicare Part B begins to pay after an annual deductible of $240 in 2024. Once you meet the deductible, you pay 20% for services, provided your doctor accepts the Medicare-approved amount as full payment.

But beware: There is no cap on this out-of-pocket expense. If, for example, you racked up $100,000 in medical bills in a given year, you would need to pay $20,000. This is on top of any charges incurred under the Part A and D umbrellas. There is no lifetime maximum.

Kathryn B. Hauer, a financial advisor at Wilson David Investment Advisors and the author of Financial Advice for Blue Collar America, warns that devastating illnesses such as cancer can cripple your finances in retirement and urges Medicare recipients to consider supplementary coverage. She notes that Medicare users who lack Medigap coverage spend 25% to 64% of their income on medical expenses.

What Parts A and B Don't Cover

Medicare Part A and Part B do not cover services such as dental care, eye exams, and hearing aids. Critically, traditional Medicare does not cover long-term care for those who live in an assisted-living facility, nursing home, or require assisted living at their home.

However, Medicare will cover acute-care hospital services for patients who are transferred from an intensive care or critical care unit. Services covered could include head trauma treatment or respiratory therapy. As mentioned earlier, a deductible applies, and benefits taper out after 60 days.

Carlos Dias Jr., founder and managing partner of Dias Wealth, notes that Medicare was never intended to provide long-term care. “To take care of these expenses, look into long-term care insurance,” Dias says.

He advises retirees to look for a life insurance policy with a long-term care rider, a specifically designed long-term care annuity (versus an annuity with a chronic care rider), or even a life settlement, which will convert an old life insurance policy into funds that can be used for long-term care.

Medicare Part C: Medicare Advantage

Medicare Part C, also known as Medicare Advantage, is offered by private insurers under contract with the federal government and typically provides a bundle of Medicare Part A, Part B, and Part D, the prescription drug benefit. If you already have coverage from a Health Maintenance Organization (HMO), they might offer similar services under a Medicare Advantage plan.

If you sign up for a Medicare Advantage plan, you continue paying your Part B premium, and whether you need to pay an additional premium depends on your provider.

The key benefits of Medicare Advantage versus original Medicare include the ability to receive additional services, such as dental and vision care. However, some plans do not offer Part D coverage and there are other pitfalls to Medicare Advantage plans, such as a limited network of doctors.

If you sign up for Medicare Part C, you can elect to have payments deducted from your Social Security benefit, in addition to fees associated with the Part D benefit. If your Medicare Part C premium is lower than what you would pay under Part B, the Social Security Administration takes the difference into account.

Medicare Part D: Prescription Drugs

Medicare Part D is an optional prescription drug benefit administered by private insurance companies and is normally (though not always) included in Medicare Advantage plans. Depending on your plan, you may need to pay a yearly deductible before eligible drug costs are covered, and some Part D plans have a co-pay.

Medicare prescription drug plans have a coverage gap that is sometimes called the Medicare Donut Hole. This describes a stage when Medicare recipients begin to pay more for prescription drugs due to hitting a spending threshold, before reaching a later threshold when additional benefits kick in.  

In 2024, the first threshold was set at $5,030. Once you and your plan spend that amount on Part D drugs, you have entered the donut hole and will pay 25% for drugs going forward.

Once your out-of-pocket costs reach the second threshold of $8,000 in 2024, you are out of the donut hole and "catastrophic coverage" begins. No coinsurance or copayment is owed for the rest of the year once $8,000 in spending is reached.

Many states have insurance options that will close the coverage gap, but these may require paying an additional premium.

Medicare Advantage vs. Medigap

If you only have Medicare Parts A and B, you might consider supplementary private insurance to help cover your out-of-pocket costs such as copays, coinsurance, and deductibles. This is where Medigap supplementary insurance comes in. While Medicare Part C works as an alternative to your original Medicare plan, Medigap works together with Parts A and B and helps fill in any coverage gaps.

There are a few important things to know about Medigap. First, you must have Medicare Parts A and B before buying a Medigap policy, as it is a supplement to Medicare and not a stand-alone policy. Secondly, you and your spouse must buy separate policies. 

Also, insurance companies can only sell a “standardized” Medigap policy. These policies are regulated by federal and state laws and provide a standard level of benefits. However, prices differ among providers, so it’s important to shop around.

"I recommend that my clients purchase Medigap policies to cover their needs,” says MoneyCoach founder Patrick Traverse. “Even though the premiums are higher, it is much easier to plan for them than what could be a large out-of-pocket outlay they might have to face if they had lesser coverage."

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