How old do you have to be to get on Medicare?

Key points

• You become eligible for Medicare when you turn 65, but you may be able to sign up at an earlier age if you have a disability or end-stage renal disease.
• Once you meet the eligibility requirements for Medicare, there are several plans you can sign up for: Medicare Part A, Part B, Part D, Medigap and Medicare Advantage.
• Most enrollees qualify for premium-free Medicare Part A, which is coverage for hospital stays, but you’ll pay premiums for the remaining plans.
• You can sign up for Original Medicare (Parts A and B) on the Social Security website, and you can sign up for a Medicare Advantage plan online or through a broker.

How old do you have to be to get Medicare?

When you reach age 65, you automatically qualify for Medicare. You don’t have to meet any other requirements.

But age isn’t the only way to qualify for Medicare. You may be eligible at a younger age if you have a disability, end-stage renal disease (meaning permanent kidney failure requiring dialysis or a transplant) or ALS. To qualify with a disability, you must have received Social Security disability payments for the past 24 months, which requires a total disability lasting a year or more.

Do you have to sign up for Medicare at 65?

You don’t necessarily have to sign up for Medicare as soon as you turn 65. Many people are still working at that age and covered by group health insurance, allowing them to skip Medicare coverage for the time being.

Tip: Even if you’re still working and have employer-sponsored health insurance, you can enroll in Medicare once you turn 65 and use it alongside your group coverage.

In that case, you’re free to wait, and you’ll get a special enrollment period for Medicare when you leave your group coverage. However, it’s often worth it to sign up for Medicare Part A at age 65 even if you’re covered by another plan. Medicare Part A is typically free, so there’s no downside to enrolling and it can supplement your other health insurance coverage.

What Medicare benefits you’re eligible for

Once you become eligible for Medicare, either due to your age or a health issue, you have several choices in Medicare plans. 

Medicare Part A and Part B are known as Original Medicare because they were the only coverage options offered when the program was created. Since then, Medicare has expanded significantly to include Part D and Medicare Advantage. Plus, Medicare Supplement plans known as Medigap are also available.

“Some people enroll in just Original Medicare, Parts A and B,” said Bob Rees, vice president of Medicare sales at eHealth. “Others may add a Part D prescription drug plan and a Medicare Supplement plan. Still others may opt instead to enroll in a Medicare Advantage plan that comprehensively manages their Medicare benefits for them, including Parts A and B and prescription drugs.”

Here’s a closer look at the different parts of Medicare.

Medicare Part A

Medicare Part A is the hospital insurance part of Medicare, covering inpatient stays and medical care in hospitals and skilled nursing facilities, as well as home health care and hospice care.

How much it costs

Most people pay nothing for Medicare Part A. You qualify for premium-free Medicare Part A at age 65 if:

• You or your spouse paid Medicare taxes at work for at least 10 years.
• You receive retirement benefits from Social Security or the Railroad Retirement Board.
• You are eligible to receive Social Security or Railroad benefits but haven’t enrolled yet.

Before age 65, you qualify for premium-free Part A if you:

• Have been entitled to Social Security or Railroad Retirement Board disability benefits for 24 months for most disabilities or in the first month of benefits of Lou Gehrig’s disease (ALS).
• Are a kidney transplant or dialysis patient.

If you don’t qualify for premium-free Medicare Part A (because you haven’t paid enough Medicare taxes when you were working), you might be able to buy it. Your premium will be either $278 or $505 a month, depending on how long you or your spouse worked and paid Medicare taxes. Like other insurance plans, Medicare Part A also requires a deductible and coinsurance.

Medicare Part B

Medicare Part B is the medical insurance portion of Medicare, covering care outside the hospital. That includes preventive care like annual visits, screenings and immunizations, and medically necessary services to diagnose or treat a medical condition. Part B covers ambulance services, medical equipment, and inpatient and outpatient mental health care.

“You may be required to have Parts A and B before you can enroll in some other forms of supplemental Medicare coverage,” said Rees.

How much it costs

You’ll pay a monthly premium for Medicare Part B, and the amount depends on your income. The standard premium is $174.70 per month. Once your income surpasses $103,000 for individual filers and $206,000 for joint filers, premiums rise, reaching $594 a month for those in the highest income tier. Medicare Part B plans require a deductible and coinsurance.

Medicare Part D

Medicare Part D, a newer addition to the program, covers prescription drugs. While it’s part of Medicare and regulated by the federal government, the plans are offered by private insurers, and coverage differs by plan. Every plan has a list of drugs, called a “formulary,” that are covered, and plans are required to cover at least two drugs in each common category. Most offer both generic and name-brand options.

How much it costs

Because Medicare Part D plans are offered by private insurers, premiums vary. The average Part D premium is $34.70 per month, and you may be required to pay an additional premium to Medicare based on your income. This extra cost ranges from $0 for those with low incomes to $81 a month for those in the highest income tier. Part D plans have deductibles and require copayments and coinsurance.

Medicare Supplement (Medigap)

Medigap is a supplemental insurance plan that many seniors purchase alongside Original Medicare. These plans, which are offered by private insurers, help fill in Medicare Part A and Part B coverage gaps. To sign up for a Medigap policy, you must be enrolled in Parts A and B.

How much it costs

Medigap premiums are based on your age and the plan you choose.

Medicare Advantage

Medicare Advantage, also known as Medicare Part C, combines all of your Medicare coverage — Parts A, B and D — into a single plan, plus adds benefits such as dental and vision coverage. 

“Many Medicare Advantage plans also come with prescription drug coverage,” said Rees. “Many also offer additional benefits outside the scope of Original Medicare — for example, things like gym membership discounts.”

How much it costs

Medicare Advantage plans are offered by private insurers, and each plan sets its own premium. The average premium for 2024 is $18.50 per month. That may seem low, but you’ll still have to pay your Medicare Part B premium. Medicare Advantage plans typically require deductibles and coinsurance.

How to sign up for Medicare

If you’re already receiving Social Security benefits when you reach 65, you won’t have to sign up for Medicare — it happens automatically. The same goes if you’re receiving benefits from the Railroad Retirement Board.

If you’re not getting retirement benefits already, you don’t have to wait until your 65th birthday to sign up for Medicare. Your initial enrollment period starts three months before the month you turn 65 and lasts for another three months after that.

You can sign up for Medicare Parts A and B through the Social Security Administration, either online, over the phone or in person. Signing up online is likely to be the quickest method.

When you sign up for Medicare affects when your coverage will start. 

• If you sign up before the month you turn 65, your coverage will start the first of your birthday month.
• If you wait until the month you turn 65, your coverage will start the following month. 
• If you sign up one month after you turn 65, you’ll get coverage two months after signing up. 
• If you sign up two or three months after turning 65, your coverage will start three months after you sign up.

If you wait longer to sign up for Medicare — perhaps because you’re already enrolled in group health insurance — you’ll be granted a special enrollment period when you lose your other health insurance coverage, and your Medicare coverage will start the month after you sign up.

Once you’ve signed up for Original Medicare, you can go about switching to a Medicare Advantage plan if you’d like. According to Rees, the best way to do that is online. The Medicare website has a plan finder that allows you to see available plans in your area. You can also go through online brokers and health marketplaces to compare plans.

“You can enroll through brick-and-mortar agents, insurance companies and some civic organizations that serve the needs of seniors and Medicare beneficiaries,” said Rees.