How Do I Know If I’m Eligible for Medicare? A Look at Age and Other Qualifications
Key takeaways:
You can sign up for Medicare during a 7-month period that begins 3 months before the month you turn 65. The federal health insurance program covers hospitalization, doctor visits, and some home healthcare.
If you have a certain condition or a long-term disability, you may qualify for Medicare before age 65.
It’s possible to be covered by Medicare and by Medicaid, a status known as dual eligibility.
Table of contents
Many people in the U.S. breathe a sigh of relief at age 65 because that’s when most qualify for Medicare. The Medicare eligibility age doesn’t always align with when Social Security benefits start. So knowing when and how to sign up for Medicare can be confusing.
More than 68 million people are enrolled in original Medicare and Medicare Advantage. It’s important not to confuse Medicare with Medicaid. Medicaid is a joint federal-state health insurance program for people with low incomes.
Below, we break down who is eligible for Medicare and when to apply.
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Who is eligible for Medicare?
You can become eligible for Medicare in one of three ways:
You are age 65 or older and meet the citizenship and residency requirements.
You have a long-term disability.
You have permanent kidney failure (end-stage renal disease) or amyotrophic lateral sclerosis (ALS), known as Lou Gehrig’s disease.
If you become eligible for Medicare by age, you can sign up during an initial enrollment period. This 7-month period starts 3 months before your 65th birthday and lasts for 3 months after. But if you wait until after your birthday to enroll, your coverage may be delayed by 1 to 3 months.
You can determine when you’ll be eligible and estimate your monthly costs by using Medicare’s online calculator.
Eligibility for premium-free Part A
Most people don’t pay a premium for Medicare Part A, which is hospital insurance. You are eligible for premium-free Part A if:
You are at least age 65 and you or a spouse (current or former) worked and paid Medicare taxes for at least 40 quarters (10 years).
You’re receiving Social Security or Railroad Retirement Board benefits.
You’re under 65 and qualify for Medicare because of kidney failure, ALS, or a long-term disability.
What does Medicare cover? Medicare — whether original Medicare (Part A and Part B) or a private Medicare Advantage plan — is comprehensive insurance coverage for hospital, outpatient, and preventive care.
When is Medicare open enrollment? Medicare’s annual open enrollment period is October 15 to December 7.
Choosing a Medigap plan. If you have original Medicare, you can buy an insurance supplement plan called Medigap to help cover out-of-pocket costs.
Will I be automatically enrolled in Medicare when I turn 65?
If you are already receiving Social Security or Railroad Retirement Board benefits at least 4 months before you are eligible for Medicare, you are automatically enrolled in premium-free Part A and Part B (unless you live in Puerto Rico). If you’re automatically enrolled, you can keep or refuse Part B, which is medical coverage for outpatient and preventive services.
Residents of Puerto Rico who qualify for automatic enrollment are signed up for premium-free Part A only. You must enroll in Part B on your own.
If you’re not automatically enrolled, the time to sign up is during your 7-month initial enrollment period around your 65th birthday.
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Can you qualify for Medicare if you are under 65?
If you are under 65, you can qualify for Medicare if:
You have received payments from Social Security Disability Insurance, known as SSDI, for 24 months.
You receive disability from the Railroad Retirement Board.
You have ALS.
You have end-stage renal disease and meet certain criteria.
Is Medicare mandatory?
You’re not required to sign up for Medicare when you’re turning 65. But delaying enrollment can cost you later on if you want the coverage.
You can have late enrollment penalties if you don’t sign up on time for:
Part A
Part B
Part D prescription coverage
Late-enrollment penalties are not one-time fees. They are ongoing charges that are usually applied as long as you’re enrolled in Medicare. They typically increase your premiums permanently.
If you’re working past 65, you can avoid late-enrollment penalties if you have comprehensive healthcare and prescription coverage that’s similar to Medicare’s benefits. In that case, you must comply with an 8-month special enrollment period that starts when your other insurance coverage ends to avoid late-enrollment penalties.
What documents do I need to apply for Medicare?
To sign up for Medicare, you’ll need several important documents:
Your birth certificate or other proof of birth
Proof of U.S. citizenship or legal residence (if you weren’t born in the U.S.)
Social Security card if you’re already drawing benefits
Information about your current health insurance — the type of coverage, effective dates of coverage
Proof of employment if applicable (a copy of your W-2 form, for example)
U.S. military discharge papers if you served before 1968
The Social Security Administration has a checklist of what you need to apply for Medicare.
Is it possible to be eligible for Medicare and Medicaid?
Medicaid is a joint federal-state health insurance program run by states that covers people with low incomes. Enrollment in both Medicare and Medicaid is called dual eligibility.
With Medicare and full Medicaid, you’ll automatically qualify for Extra Help. This subsidy provides financial assistance for Medicare Part D drug coverage costs.
How can you become eligible for Medicare supplement insurance (Medigap)?
Original Medicare enrollees can buy supplement insurance, known as Medigap. People with Medicare Advantage aren’t eligible for Medigap because these plans have an out-of-pocket limit.
There are 10 types of Medigap plans. They have letter names: A, B, C, D, F, G, K, L, M, and N. All plans with the same letter name have the same benefits; only the premiums are different.
Premiums vary by plan and state, but they averaged $217 per month nationwide in 2023. It’s important to note that you can be subject to medical underwriting if you switched from Medicare Advantage to original Medicare. Medical underwriting may also result if you’re beyond your one-time, Medigap open enrollment period. This is the first 6 months you’re both 65 and enrolled in Part B. Medical underwriting is a health evaluation that can exclude you from Medigap coverage.
Get help understanding your benefits
Making Medicare choices and understanding the program can be daunting. The State Health Insurance Assistance Program, known as SHIP, can help you weigh your options. SHIP counselors provide free, unbiased advice to people eligible for Medicare and their caregivers. You can get help from a SHIP counselor near you in person or by phone.
You can also find answers to your Medicare questions by visiting medicare.gov or calling 1-800-MEDICARE (1-800-633-4227).
Medicare also has a free handbook, Medicare & You, that provides detailed information in different languages.
The bottom line
Medicare is a federal health insurance program for people ages 65 and older as well as younger people with certain conditions and long-term disabilities. If you’re not automatically enrolled in Medicare, it’s important to sign up during your 7-month initial enrollment period to avoid late-enrollment penalties. There’s an exception to the initial enrollment period and late-enrollment penalties if you’re working past 65 and you have health insurance and prescription coverage comparable to Medicare’s benefits. If you have original Medicare and want a Medicare supplement plan, known as Medigap, it’s important to sign up during your one-time, 6-month open enrollment period to avoid the risk of medical underwriting preventing you from buying a plan.
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References
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