Understanding Medicare Eligibility: Who Can Enroll in the Program?

Who Is Eligible For Medicare?

The general guidelines for Medicare eligibility are straightforward: The program is for people 65 or older or younger than 65 with disabilities or End-Stage Renal Disease or Amyotrophic Lateral Sclerosis (ALS).

However, additional eligibility rules exist for various Medicare programs, such as Medicare Advantage, Medicare Supplement Insurance, Medicare Part D plans, and Medicare Savings Programs. Understanding these rules helps beneficiaries enroll in any programs they’re eligible to join. Read on for the full story on gaining eligibility for many of the most popular Medicare programs on the market.

General Criteria For Medicare Criteria 

While there are some nuances to Medicare Criteria, they are generally determined by the following:

• Age
• Citizenship
• Place of Residence
• Work History
• Pre-existing Conditions

Age or Disability Requirements 

The Medicare eligibility age is 65. Some people are eligible for Medicare before 65 if they have the following:

• Certain disabilities: People who receive Social Security Disability Insurance (SSDI) benefits are automatically enrolled in Medicare after a 24-month waiting period. This waiting period is waived for people with Lou Gehrig’s Disease or ALS.
• End-Stage Renal Disease: People with permanent kidney failure who need regular dialysis or a kidney transplant may be eligible for Medicare.

Citizenship and Residency Requirements

In general, Medicare is available to people who are either U.S. citizens or lawfully admitted permanent residents. Residency requirements may also apply. For instance, some lawfully admitted non-citizens must live in the U.S. for at least five continuous years before applying.

Work History Requirements 

The Medicare program also has work history requirements, varying depending on your eligibility category.

• Age 65+: To receive premium-free Part A, consumers (or their spouses) must have worked and paid Medicare taxes for at least ten years. This includes self-employed or government workers who pay into Medicare.
• Under 65 with Disabilities: Work requirements are set by SSDI and vary based on the age the disability began.
• End-Stage Renal Disease: Consumers must have enough work history to get SSDI or Social Security retirement or have a spouse or parent with sufficient work history.

Medicare Part A: Hospital Insurance Eligibility

Medicare Part A (Hospital Insurance) is the part of Medicare that covers inpatient hospital care and some related services. People who are eligible for Medicare are also eligible for Part A. However, some criteria determine how much enrollees pay for their Part A coverage.

Most Medicare beneficiaries are eligible for premium-free Part A if they have a long enough work history, ten years in most cases. Beneficiaries who do not meet the work history requirements pay a premium for their Part A coverage: In 2023, the premium is either $278 or $506 per month.

How to Enroll In Part A

Part A enrollment is automatic for people already receiving benefits from Social Security or the Railroad Retirement Board. Eligible people who will not be automatically enrolled can contact Social Security during the next applicable enrollment period:

• Initial Enrollment Period: A 7-month-long window that starts three months before you turn 65.
• General Enrollment Period: Jan. 1 to Mar. 31 each year.
• Special Enrollment Period: Available for people who experience qualifying life events.

People who need to pay a premium for Part A pay late enrollment penalties if they delay enrollment. This penalty is calculated by multiplying 10% of the Part A premium by the number of full 12-month periods the individual could have had coverage but didn’t enroll. The penalty is added to the Part A premium and must be paid for as long as the individual has Part A coverage.

Medicare Part B: Medical Insurance Eligibility 

Medicare Part B (Medical Insurance) is the part of Medicare that covers outpatient care like doctor services or lab tests. People eligible for premium-free Part A are also eligible for Part B. People who need to buy Part A are eligible for Part B as long as they meet the following requirements:

• Age 65 or older
• U.S. resident
• U.S. citizen or lawfully admitted permanent resident

Most beneficiaries are eligible to pay the standard Part B premium, which in 2023 is $164.90 per month. Higher-income individuals pay more, depending on their incomes.

How to Enroll In Part B

Some people get Part B automatically because they’re already receiving benefits from Social Security or the Railroad Retirement Board. People not getting these benefits can contact Social Security to enroll in Part B.

The same enrollment periods apply to both Part A and Part B, so beneficiaries can enroll during the next applicable period:

• Initial Enrollment Period: The 7-month period that starts three months before you turn 65.
• General Enrollment Period: Jan. 1 to Mar. 31 each year.
• Special Enrollment Period: An opportunity to enroll in Medicare if certain events happen in your life.

People who wait to enroll in Part B may also face late enrollment penalties. If someone is eligible for Medicare Part B but delays enrolling past their initial enrollment period, they may be subject to a late enrollment penalty. The penalty is calculated by adding 10% to the monthly Part B premium for each full 12-month period the individual could have had Part B coverage but didn’t enroll. This penalty is then added to the premium and must be paid for as long as the individual has Part B coverage.

The Part A and Part B enrollment penalties in Medicare differ in terms of enrollment timing, penalty calculation, and coverage start date. Part A enrollment is typically automatic, while Part B requires active enrollment during the Initial Enrollment Period. The penalties are calculated differently, with Part A based on 10% of the premium and Part B adding 10% to the monthly premium for each period of eligibility missed. Additionally, the effective dates for coverage can vary, with Part A potentially starting retroactively and Part B typically starting on the month after you sign up.

Medicare Part C: Medicare Advantage Eligibility 

Medicare Advantage Plans offer a different way for people with Medicare to get their health benefits. Private companies sell these plans but are still Medicare, and the eligibility requirements are largely the same. Typically, beneficiaries can join a Medicare Advantage plan if they:

• Are enrolled in Part A and Part B.
• Live inside the plan’s service area.

Additional requirements apply to Special Needs Plans, a type of Medicare Advantage Plan tailored to people with complex healthcare needs. 

How to Enroll In Part C

To join a Medicare Advantage Plan, contact either Medicare or your preferred plan during the next applicable enrollment period:

• Initial Enrollment Period: The 7-month period that starts three months before you become eligible for Medicare.
• General Enrollment Period: For people who missed their IEP, the next chance to enroll is between Jan. 1 to Mar. 31. This enrollment period only applies if you are already enrolled in a Medicare Advantage plan and want to switch to Original Medicare or a different Advantage plan.
• Special Enrollment Period: People who have a SEP to enroll in Part A and B can use this period to join a Medicare Advantage Plan.
• Annual Enrollment Period: Current Medicare beneficiaries can make coverage changes from Oct. 15 to Dec. 7 each year.

Switch From Original Medicare to Medicare Advantage 

People with Original Medicare can switch to Medicare Advantage during the:

•  Annual Enrollment Period: Oct. 15 to Dec. 7 each year. The new coverage starts Jan. 1 of the next year. 

Switch From One Medicare Advantage Plan to Another 

People who are already in a Medicare Advantage Plan have two opportunities each year to switch plans: 

• Annual Enrollment Period: Oct. 15 to Dec. 7
• Medicare Advantage Open Enrollment Period: Jan. 1 to Mar. 31

Certain life events, such as moving outside the plan’s service area, trigger a Special Enrollment Period to switch plans. Those events include:

1. Moving out of your plan’s service area: If you move outside of your current Medicare Advantage plan’s service area, you qualify for a SEP to select a new plan that serves your new location.
2. Losing existing coverage: If you have other health coverage, such as employer-sponsored health insurance, and that coverage ends or changes, you may be eligible for a SEP to enroll in a Medicare Advantage plan.
3. Qualifying for Extra Help: If you become eligible for Extra Help, a program that assists with Medicare prescription drug costs, you can use the SEP to join a Medicare Advantage plan or switch to a different one.
4. Institutional status: If you move into, live in, or move out of certain institutions like a skilled nursing facility or long-term care hospital, you may have a SEP to enroll in or switch Medicare Advantage plans.
5. Dual-eligible individuals: Those who are eligible for both Medicare and Medicaid (dual-eligible) may have additional opportunities to enroll or switch Medicare Advantage plans outside of the regular enrollment periods.

Medicare Advantage Special Needs Plans (SNP) Eligibility 

SNPs are Medicare Advantage Plans that are only available to people with specific health conditions or circumstances. These plans design their benefit packages, provider networks, and formularies to meet their members’ needs. Beneficiaries enroll in SNPs to get more support in managing their health.

For example, an SNP for people with diabetes might include a network of providers specializing in treating this condition. It may cover benefits not part of Original Medicare, such as fitness programs, routine foot care, or healthy meal delivery services.

Dual-Eligible SNP (D-SNP)

Dual-Eligible SNPs are available to people eligible for Medicare and Medicaid. Categories of Medicaid eligibility that satisfy this requirement include:

• Full Medicaid coverage
• Qualified Medicare Beneficiary
• Specified Low-Income Medicare Beneficiary
• Qualifying Individual 
• Qualified Disabled and Working Individual

Chronic Condition SNP (C-SNP) 

Chronic Condition SNPs limit enrollment to people diagnosed with certain severe or disabling health conditions. Beneficiaries are eligible if they have a condition the plan targets, as confirmed by their doctor. Conditions C-SNPs focus on include:

• Cancer
• Diabetes
• Heart failure
• Stroke
• Lung disorders
• Dementia

Institutional SNP (I-SNP) 

Institutional SNPs are available to people who, for at least 90 days, need the level of care provided by any of the following institutions:

• Skilled nursing facility
• Nursing facility
• Intermediate care facility
• Psychiatric hospital or unit
• Rehabilitation hospital or unit
• Long-term care hospital

Medicare Part D: Prescription Drug Plan Eligibility 

Part D provides prescription drug coverage to those with Original Medicare. It’s available through either standalone Part D plans or Medicare Advantage Plans that include drug coverage. Anyone who’s eligible for Medicare is also eligible for Part D, though some criteria affect plan availability.

Both Medicare Advantage plans that include drug coverage and standalone Medicare drug plans have service areas. Beneficiaries can join if they live in a county the plan covers.

Standalone Part D plans are compatible with Original Medicare. They also work with some types of Medicare Advantage Plans, such as Private Fee-for-Service Plans.

How to Enroll In Medicare Part D for Drug Coverage 

To achieve the coverage provided by Medicare Part D, one either join a Medicare Advantage Plan with drug coverage or purchase a standalone Part D plan.

These changes can only be made during certain times of the year:

• Initial Enrollment Period: Timing varies
• Annual Enrollment Period: Oct. 15 to Dec. 15 
• Medicare Advantage Open Enrollment Period: Jan. 1 to Mar. 31
• Special Enrollment Periods: Timing varies

People who delay signing up for Part D may pay late enrollment penalties. The penalty adds 1% of the national base beneficiary premium ($32.74 in 2023) for each full month without drug coverage.

Switch From One Part D Plan to Another 

Beneficiaries are allowed to switch from one Part D plan to another during the Annual Enrollment Period, which runs from Oct. 15 to Dec. 7. Certain life events, such as moving to a new address or losing your current coverage, create a Special Enrollment Period to switch plans.

Dropping Part D Coverage 

People who no longer want their Part D coverage can leave their plan during the Annual Enrollment Period. It’s also possible to drop Part D coverage if certain life events occur, such as getting the chance to get other coverage through work.

Medicare Supplement Insurance, or Medigap Eligibility 

Medicare Supplement Insurance is optional coverage that complements Original Medicare. It helps cover some costs that Original Medicare does not, such as deductibles and copayments. Here are the general rules for eligibility for Medicare Supplement Insurance:

• Have Original Medicare, not Medicare Advantage
• Are enrolled in both Part A and Part B
• Are 65 or older
• Pass medical underwriting, except during set enrollment periods

Eligibility for Medicare Supplement Insurance varies by location. Some states extend eligibility to Medicare beneficiaries who are younger than 65. Others do not allow insurers to use medical underwriting.

How to Enroll In Medigap 

Medigap policies do not have an annual enrollment period, so it’s possible to sign up for Medigap at any time of the year. However, Medicare recommends buying a policy during your Medigap Open Enrollment Period. 

The Medigap Open Enrollment Period is a 6-month period that starts on the first of the month when you’re both 65 or older and enrolled in Medicare Part B. During this time, you can buy any policy for sale in your state without medical underwriting. 

Once this one-time period has passed, Medigap insurers are typically allowed to deny coverage to people with health issues, except in specific situations.

Switch From One Medigap Plan to Another 

Federal law gives people with Medigap the right to buy a new policy in certain situations. For example, when their employer or retiree-sponsored health plan ends.

Several states allow beneficiaries to switch Medigap policies each year during their birthday month. Rules vary, but enrollees typically can only switch to a plan with equal or lesser coverage.

Dropping Medigap Coverage 

Medigap has no disenrollment period, so beneficiaries can drop their coverage anytime. However, be aware that once you drop a policy, you may not be able to get it back if you change your mind.

Medicare Savings Programs Eligibility 

Medicare Savings Programs are Medicaid-run programs that help low-income people pay for their Medicare coverage. Some programs help pay for Part A and/or Part B premiums. Others help pay for out-of-pocket costs in Original Medicare, including deductibles, copayments, and coinsurance.

There are four Medicare Savings Programs, each with slightly different eligibility requirements, including:

Qualified Medicare Beneficiary (QMB) Program 

The QMB program is for Medicare beneficiaries with very low incomes and limited resources. It helps cover the premiums for both Part A and Part B, as well as deductibles, coinsurance, and copayments for Medicare-covered services.

Eligibility Criteria 

• Income limit: $1,235 per month for individuals or $1,663 for couples (higher in Alaska and Hawaii)
• Resource limit: $9,090 for individuals or $13,630 for couples

Specified Low-Income Medicare Beneficiary (SLMB) Program 

The SLMB program is for Medicare beneficiaries with low incomes and limited resources. It helps people with Part A and Part B pay for their Part B premiums.

Eligibility Criteria 

• Income limit: $1,478 per month for individuals or $1,992 for couples (higher in Alaska and Hawaii)
• Resource limit: $9,090 for individuals or $13,630 for couples

Qualified Individual (QI) Program 

The QI program helps people with modest incomes and few resources pay their Part B premiums. States pay for this program from a limited pool of funds, so benefits are available on a first-come, first-served basis.

Eligibility Criteria

• Income limit: $1,660 per month for individuals or $2,239 for couples (higher in Alaska and Hawaii)
• Resource limit: $9,090 for individuals or $13,630 for couples

Qualified Disabled and Working Individuals (QDWI) Program 

The QDWI program is for people with disabilities who lost their Social Security disability benefits and premium-free Medicare Part A because they returned to work. It helps pay for Part A premiums.

Eligibility Criteria 

• Income limit: $4,945 per month for individuals or $6,659 for couples (higher in Alaska and Hawaii)
• Resource limit: $4,000 for individuals or $6,000 for couples

You’re Eligible: What’s Next? 

After learning who is eligible for Medicare and confirming that you can enroll, prepare to sign up for your plan of choice. Mark the next applicable enrollment period on your calendar and gather the information you need to enroll.

If you’re new to Medicare, be prepared to provide information about your current health insurance. Medicare may ask for proof of your age, citizenship, or legal residency, so gather relevant documentation, such as your birth certificate or passport.

If you already have Medicare, you’ll need the information found on your Medicare card to enroll in a Medicare Advantage, Part D, or Medigap plan. Applying for a Medicare Savings Program requires more information, so ask your state Medicaid office what documents to gather.

Putting It All Together 

The general Medicare eligibility age is 65, but some people can enroll at a younger age due to disabilities or End-Stage Renal Disease. Beyond these age or disability requirements, the program also has criteria for citizenship, residency, and work history. 

Each Medicare plan choice has some additional eligibility requirements. If you want to join a Medicare Advantage Plan, Part D plan, or Medigap plan, or apply for a Medicare Savings Program, be sure to review these requirements.

For more detailed information about who is eligible for Medicare, call Medicare or talk to a trusted Medicare agent.