20 Key Answers to Sign Up for Medicare

Medicare, the United States federal health program for people 65 years and older, and also for those with certain disabilities or kidney disease, has provided medical and hospital care, among other services, for more than 50 years.

The decision to unify a universal health system for seniors has helped grandparents have quality medical care at reasonable prices or for free. The following are answers to common questions as Medicare Open Enrollment begins.

20 Key Answers to Sign Up for Medicare
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When is the Medicare Open Enrollment Period?

The Medicare Open Enrollment period runs from October 15 through December 7 each year. During this period, people on Medicare can make a change in their coverage. If you are covered by Medicare, and you are interested in reviewing and comparing your Medicare coverage options, make sure the plans you are considering during the Medicare Open Enrollment period are Medicare plans, not Marketplace plans.

Medicare plans are not sold through the federal or state Marketplace websites. You can review and compare your Medicare options on the Medicare Plan Finder, a searchable tool on the Medicare.gov website, or by calling 1-800-MEDICARE (1-800-633-4227). You can also contact the State Health Insurance Assistance Program (SHIP) in your state. SHIPs offer local, personalized counseling and assistance to people with Medicare and their families. You can call 877-839-2675 to get the phone number for the SHIP in your state.

When a person should sign up for Medicare?

A person can sign up for Medicare three months before the month of their 65th birthday and three months after. There is a window of seven months to join.

If you don't sign up for Part A within that period, you'll have to pay a penalty to sign up for the plan, and you could pay higher monthly premiums. Even if you are still working, and you are covered by your employer health plan, you still need to enroll in Medicare Part A.

You can sign up for Medicare Part B when you've signed up for Part A, or you can wait until you need that kind of coverage.

How can I find out if my doctor accepts Medicare?

Most doctors in the United States accept Medicare. To find a list of doctors in your area who accept Medicare and agree not to bill you for more than the approved Medicare amount for your visit or procedure, go to Medicare’s Care Compare website , select “Doctors & clinicians” under the Provider Type dropdown menu, and look for providers noted as charging the Medicare-approved amount. If you do not have access to a computer, you can also call 1-800-MEDICARE (1-800-633-4227), or call your doctor’s office and ask before you schedule an appointment.

What do Medicare Part A and Part B cover?

Medicare Part A covers services and supplies needed to treat an illness or medical condition received at:

  • Hospital care
  • Skilled Nursing Facility Care
  • Hospice care
  • Home medical visits

Services and supplies provided in a hospital or facility may include:

  • Care provided by doctors, nurses, and other health care providers
  • Medicines
  • nursing care
  • Therapy to help with speaking, swallowing, movement, bathing, dressing, and other daily tasks.
  • Imaging and laboratory tests
  • Surgeries and procedures
  • Wheelchairs, walkers and other equipment

Most people do not pay a monthly premium for Part A.

Medicare Part B helps pay for treatment and services provided on an outpatient basis. Outpatient care can be received at:

  • An emergency room or another area of ​​the hospital, but not an inpatient
  • A health care provider's office (including doctors, nurses, therapists, and others)
  • Surgery centers
  • A laboratory or imaging testing center
  • Your house

It also pays for preventive health services, such as:

  • Well-being visits and other preventive services, such as flu and pneumonia shots and mammograms
  • Surgical procedures
  • Laboratory tests and X-rays
  • Drugs and medications that you cannot administer yourself, such as intravenously administered medications
  • Feeding tubes
  • Consultations with a provider
  • Wheelchairs, walkers, and some other supplies

Most people pay a monthly premium for Part B.

What does Part D cover?

If you need prescription drug coverage, you can choose a Medicare Prescription Drug Plan (Plan D). This coverage is provided by private insurance companies approved by Medicare.

You can't choose a plan from Part D if you have a Medicare Advantage plan because the coverage is provided by those plans.

What is Medicare Advantage?

Medicare Advantage (MA) plans provide the same benefits as Part A, Part B, and Part D. This means you have coverage for medical and hospital care as well as prescription drugs, in a single plan.

MA plans are offered by private insurance companies as long as they work with Medicare. Basically:

  • You pay a monthly premium for this type of plan.
  • You generally must visit doctors, hospitals, and other providers that work with your plan's network or you'll have to pay more money.
  • MA plans cover all services covered by Original Medicare (part A and part B).
  • They also offer additional coverage such as vision, hearing, dental, and prescription drugs. In some cases, you may need to pay extra for additional benefits like dental care.

What is Medigap?

Medigap is a Medicare supplement insurance policy sold by private companies. Helps pay expenses like deductibles, copays, and coinsurance. To get a Medigap policy, you must have an Original Medicare plan (part A and part B). You would be paying the private insurance company a monthly premium for the Medigap policy, in addition to the monthly Part B premium you pay to Medicare.

Can immigrants enroll in Medicare?

It depends. Residents of the U.S., including citizens and permanent residents, are eligible for premium-free Medicare Part A if they have worked at least 40 quarters (10 years) in jobs where they or their spouses paid Medicare payroll taxes and are at least 65 years old. 

Legal immigrants who are age 65 or older who do not have this work history can purchase Medicare Part A after residing legally in the U.S. for five years continuously. Legal immigrants (non-citizen permanent residents) under age 65 with disabilities may also qualify for Medicare, but typically first must meet the same eligibility requirements for SSDI (disability benefits) that apply to citizens, which are based on work history, paying Social Security taxes on income, and having enough years of Social Security taxes accumulated to equal between 20 and 40 work credits (5-10 years). 

New immigrants are not eligible for Medicare regardless of their age. Once immigrants meet the residency requirements, eligibility and enrollment works the same as it does for others.

If I am an immigrant and have never worked in the United States, can I still have Medicare?

People 65 years of age or older who have not worked in the United States, who have worked for less than the required time, or who are not married to someone who has Medicare, which makes them eligible, can access the adult program Seniors paying.

The vast majority of Medicare beneficiaries access the program because they have worked for at least 10 years (40 credits) in the country, making contributions to social security. Or because they meet other eligibility requirements to enroll.

But there is a percentage of older people, immigrants or people who have been outside the formal work circuits and who have not made contributions. These people can still have Medicare by paying the monthly premiums for Parts A, B, and D.

What are the options for those over 65 who cannot enroll in Medicare?

Undocumented senior immigrants who do not qualify for Medicare can buy health insurance through the marketplaces established by the Affordable Care Act (ACA).

Depending on the state, they may be able to find out in the federal insurance market (healthcare.gov) or in the state market.

As people aging, the insurance begins to get more expensive. Even Bronze plans, which are the cheapest ones, can mean a premium of $800 or more for a senior.

Although Obamacare states that insurers cannot discriminate against or deny coverage to people with pre-existing conditions (most people over 65 have at least one chronic condition), premiums—the monthly payment for the health plan—for this group of population is always higher.

Federally qualified community health centers may be another health care option for seniors without Medicare. These centers already serve nearly 2 million beneficiaries of the program throughout the country, and have specialists prepared to deal with the health problems of this population.

If I am still working and my employer offers health benefits for retirees, ¿Should I sign up for Medicare when I turn 65?

For most people with retiree health benefits, it makes sense to sign up for Medicare when you're eligible for the first time. Retiree health plans are generally designed to supplement Medicare and may not pay your medical costs during any period you were eligible for Medicare but did not enroll.

You should review any information provided by your employer to make sure you understand how your retiree health benefits coordinate with Medicare. For example, some employers offer a fixed payment that retirees can use to purchase supplemental insurance. Others offer retiree health benefits exclusively through Medicare Advantage plans.

Be sure to find out if your health plan provides prescription drug coverage as good as Medicare Part D plans; if not, you'll need to join a Medicare prescription drug plan to avoid a late enrollment penalty.

If you're not receiving Social Security benefits at age 65 when you're first eligible for Medicare, you'll need to sign up for Part A and Part B. You can sign up for Medicare online at socialsecurity.gov/retirement, by calling Social Security, or at your local Social Security office. If you're already receiving your Social Security benefits, you should automatically enroll in Part A and Part B when you turn 65.

Is the Medicare Open Enrollment period the same as the Marketplace Open Enrollment period?

There is some overlap in the enrollment periods for Medicare and the Marketplaces, but they are not the same. The Medicare Open Enrollment period runs from October 15 through December 7 each year. For Marketplace coverage in 2023, the open enrollment period will run from November 1, 2022 through January 15, 2023 in states that use the Healthcare.gov website; states that run their own marketplaces may have a longer open enrollment period for 2023.

If you are covered by Medicare, and you are interested in reviewing and comparing your Medicare coverage options, make sure the plans you are considering during the Medicare Open Enrollment period are Medicare plans, not Marketplace plans. Medicare plans are not sold through the federal or state Marketplace websites. 

You can review and compare your Medicare options on the Medicare Plan Finder, a searchable tool on the Medicare.gov website, or by calling 1-800-MEDICARE (1-800-633-4227). You can also contact the State Health Insurance Assistance Program (SHIP) in your state. SHIPs offer local, personalized counseling and assistance to people with Medicare and their families. You can call 877-839-2675 to get the phone number for the SHIP in your state.

I am having a hard time affording my Medicare Part D drug coverage. Are there any options for me?

You may want to find out if you qualify for extra assistance with your Part D plan premiums and cost sharing, if your income and assets are low enough. Through the Part D Low-Income Subsidy program, sometimes referred to as “Extra Help”, additional premium and cost-sharing assistance is available for Part D enrollees with low incomes (less than 150% of poverty, which was $20,385 for individuals/ $27,465 for married couples in 2022) and modest assets (less than $15,510 for individuals/$30,950 for couples in 2022). 

To find out whether you might qualify for Extra Help, you can contact the State Health Insurance Assistance Program (SHIP) in your state, the State Medical Assistance Office (Medicaid), or the Social Security Administration. You can apply for Extra Help at any time. There’s no cost to apply for Extra Help, so you should apply even if you’re not sure if you qualify.

If you apply and qualify for Extra Help, you should check to make sure that the Part D plan you are enrolled in is available to you for zero premium (known as a “benchmark” plan). Only a subset of stand-alone Part D drug plans qualify as premium-free for enrollees receiving Extra Help in each area. 

All people receiving Extra Help can select any plan offered in their area, but if you are receiving Extra Help and you enroll in a non-benchmark plan, you must pay some portion of your chosen plan’s monthly premium. If you are not currently in a benchmark plan, you can switch plans when you become eligible for Extra Help. 

You can compare your plan options and enroll in a drug plan by going to the Medicare Plan Finder, a searchable tool on the Medicare.gov website, or by calling 1-800-MEDICARE (1-800-633-4227). You can also contact the State Health Insurance Assistance Program (SHIP) in your state. SHIPs offer local, personalized counseling and assistance to people with Medicare and their families. You can call 877-839-2675 to get the phone number for the SHIP in your state.

Is a person under the age of 65 with a disability eligible for Medicare?

It depends on how long you've been receiving Social Security Disability Insurance (SSDI) payments. You are automatically enrolled in Medicare Part A and Part B after you have received SSDI payments for two years.

However, people with disabilities who have amyotrophic lateral sclerosis (ALS) do not have to wait two years and are eligible for Medicare immediately after receiving SSDI; and people with End-Stage Renal Disease (ESRD) are eligible for Medicare three months after starting dialysis treatment or immediately after receiving a kidney transplant.

Does Medicare cover colonoscopy?

Medicare covers screening colonoscopies once every 24 months if the patient is at high risk for colorectal cancer. If that risk isn't high, you pay for the test once every 120 months or 48 months after a previous flexible sigmoidoscopy.

There is no minimum age requirement.

As the National Library of Medicine explains, endoscopes have a small camera at the tip of a long, thin tube. The procedure allows the doctor to see things like swollen tissue, abnormal growths, and ulcers. Colonoscopy allows you to see the entire colon and rectum. Sigmoidoscopy looks only at the rectum and lower colon.

You pay nothing for this test if your doctor or other qualified health care provider accepts assignment.

However, if a polyp or other tissue is found and removed during your colonoscopy, you may have to pay 20% of the Medicare-approved amount for your doctor's services and a copay if the procedure is performed in a hospital. The Part B deductible does not apply.

Does Medicare cover hip replacement surgery?

Medicare covers hip replacement surgery when the doctor says it's medically necessary.

The doctor must document that hip replacement surgery, or arthroplasty, can improve mobility when other treatments, such as medications, physical therapy, and the use of walkers for walking, have not been effective in reducing pain and increasing function of the joint .

Arthroplasty is performed more than 100,000 times a year in the United States and has a 90% success rate, according to a medicare.gov document.

The surgery can cost between $30,000 and $40,000, but Medicare helps cover the big costs.

Does Medicare cover dental care?

Medicare does not cover most dental care, routine procedures like cleanings, fillings, or extractions, or dental supplies like dentures, plates, or dental appliances.

Program beneficiaries can use Medicare Part A, which covers inpatient and hospital care, for certain mouth-related services:

  • May pay for certain dental services that the patient needs to receive during their hospital stay.
  • It can also take care of inpatient hospital care if they need to have complicated or emergency dental procedures, even though the dental care itself is not covered.

Medicare was not originally designed to include routine dental care; therefore, Medicare coverage of dental expenses is limited to situations in which dental treatment is an integral part of other medical treatment. For example:

  • An extraction before radiation treatment for oral cancer or
  • Jaw reconstruction after an accident

Unfortunately, if you have no other insurance, your out-of-pocket cost for dental procedures is 100%.

What is a medical home? Can I enroll in one during the Medicare enrollment period?

Medical homes are typically team-based primary care medical practices that provide the majority of their patients' medical care, either directly or through coordination with other specialists and facilities.

Medicare is testing various medical home models across the country to determine if increased investment in primary care through medical homes can lead to better quality of care and lower overall health care spending.

Patients are not specifically “enrolled” in a medical home. If your primary care physician participates in a medical home model, you can still seek services from any Medicare provider outside of the primary care medical practice.

Does Medicare help with end of life planning?

"Advanced care planning" is a service that includes discussions between patients and their doctors before a terminal or deteriorating illness progresses, to decide what type of care the patient wants to receive during the last days of life.


Approximately eight in 10 of the nearly 2.6 million people who die in the United States in a typical year are Medicare beneficiaries, making the federal health program for the elderly the insurer that provides the most medical care during the last year of life.


The overall high cost of medical care received in the last year of life is not surprising given that many of those who died suffered from multiple serious and complex conditions.

Sources: KFF, CMS

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