Medicare is a federal program that provides health insurance for many older people in the United States. Medicare eligibility begins three months before you turn 65 years old, but those younger than 65 with end-stage kidney disease or amyotrophic lateral sclerosis — ALS or Lou Gehrig’s disease — may be eligible for Medicare as well. Learning more about Medicare eligibility, available options, and how to enroll can help you take advantage of the benefits this program provides.
Medicare Requirements
Automatic Enrollment Requirements
Medicare enrollment may be automatic if the following criteria are met:
- You live in the United States
- You receive Social Security or Railroad Retirement Board (RRB) benefits for at least 4 months before you turn 65
Those who are automatically enrolled also often can get premium-free Part A coverage.
Manual Enrollment Requirements
Eligibility for manual enrollment in Medicare include living in the United States and meeting at least one of the following criteria:
- You are at least 65 years old
- You have been diagnosed with end-stage renal disease or amyotrophic lateral sclerosis
- You have a disability for which you’ve received Social Security Disability benefits for at least 24 months
If you’re not enrolled automatically in Medicare, starting coverage during the initial enrollment period (IEP) can help you get coverage as soon as possible. This 7-month window starts 3 months before the month of your 65th birthday, and it lasts for 3 months after your birthday month. For example, if your birthday is in May, your IEP would begin on February 1 and end August 31.
If you enroll in the first 3 months of your IEP, your Medicare coverage starts on the first day of the month you turn 65. If you enroll during months 4 through 7 of your IEP, Medicare Part A coverage is retroactive to this time, while your Part B coverage may be delayed for 2 to 3 months.
People who do not receive Social Security or RRB benefits can apply for Medicare by contacting their local Social Security office or speaking with a trusted Medicare agent when their initial enrollment period begins.
Exceptions to the Medicare Eligibility Age
Medicare requires most people to turn 65 before getting coverage, but there are some exceptions. People who receive Social Security or RRB benefits because of a disability for 24 months gain eligibility for Medicare Part A. Disabled federal, state, and local government employees who are not eligible for Social Security or RRB benefits may become entitled to Part A after 29 months. There’s no waiting period for people with ALS, and they can claim Medicare Part A benefits during the first month they get Social Security or RRB benefits.
Children are not eligible for Medicare, but people over 18 can become eligibleif they receive Social Security or RRB for at least 24 months. This means that Medicare disability benefits does not usually start until someone is at least 20 years old. However, those under 20 can get Medicare if they have end-stage kidney disease or ALS.
Medicare Enrollment Periods
Medicare has an extensive history in the United States. President Theodore Roosevelt introduced a version of it when he included health insurance in his 1912 platform, but legislation for Medicare did not pass until Lyndon Johnson signed it into law in 1965.
It is now the primary provider of health insurance for those 65 and older. In October 2021, Original Medicare enrollment was over 36 million, and the total Medicare enrollment was nearly 64 million. Learn the differences between your Medicare options of Original Medicare, Medicare Advantage, Medicare Part D, and Medicare Supplement insurance.
Original Medicare
Original Medicare consists of Medicare Part A and Part B. Part A works as hospital insurance, and Part B covers many other medical expenses. Those with Original Medicare can use any doctor or hospital that accepts Medicare in the United States, meaning you can seek care across state lines.
Medicare Part A covers services like hospitalization and care in a skilled nursing facility to help you recover after an illness or injury. In each benefit period, Part A covers all hospital stays up to 60 days, after which policyholdersmust pay a coinsurance fee each day from day 61 until the 90th day of hospitalization, or up until they exhaust their lifetime reserve days. Part A includes a lifetime reserve of 60 hospital days, meaning beneficiaries may draw from this reserve any time they are hospitalized for longer than 90 days in a benefit period.
Most Medicare beneficiaries are eligible for premium-free Part A, but some may pay $278 or $506 each month for coverage in 2023, depending on how much they have paid into their Medicare taxes.
Medicare Part B covers services like doctor’s visits, diagnostic tests, and preventative care. After meeting the deductible of $226 in 2023, beneficiaries typically pay 20% of the approved Medicare costs for care, while Part B pays the remaining 80%.
The premium for Part B is $164.90 in 2023, but it could be higher for those with higher incomes. For example, if your 2021 individual tax return was $97,000 or less, you would pay $164.90 per month for your premium in 2023. However, if your individual tax return in 2021 was between $97,001 and $123,000, you would pay $230.80 per month.
Enrollment Periods For Original Medicare
- Initial Enrollment Period: 3 months before your 65th birthday, your birthday month, and 3 months afterwards
- Annual Enrollment Period: October 15 to December 7
Medicare Advantage
Medicare Advantage, also called Medicare Part C, is an alternative to Original Medicare. All Medicare Advantage plans must include Parts A and B, and many also include additional benefits, such as Medicare Part D drug coverage, dental, and vision coverage. However, these plans are offered by private insurance companies, so premiums and other out-of-pocket costs are set by the insurer. In addition, most Medicare Advantage plans are managed care plans like PPOs and HMOs, so beneficiaries must seek care from the plan’s in-network providers, making it less portable than Original Medicare.
Enrollment Periods For Medicare Advantage
- Initial Enrollment Period: 3 months before your 65th birthday, your birthday month, and 3 months afterwards
- Annual Enrollment Period: October 15 to December 7
- Medicare Advantage Open Enrollment Period: January 1 to March 31
Medicare Part D
Medicare Part D provides prescription drug coverage. It is offered by private insurance companies, and can be purchased as a stand-alone plan or as part of a Medicare Advantage plan. Each Part D plan has its own formulary or list of covered prescription drugs, though Medicare mandates that it must cover at least two drugs per drug category. However, if your prescribing doctor believes that the drugs in your plan’s formulary will not work well for your condition, you can ask for an exception. A statement from the prescriber explaining the medical reason for the exception is usually required.
Enrollment Periods For Medicare Part D
- Initial Enrollment Period: 3 months before your 65th birthday, your birthday month, and 3 months afterwards
- Annual Enrollment Period: October 15 to December 7
- Medicare Advantage Open Enrollment Period: January 1 to March 31
Medicare Supplement, or Medigap
Medicare Supplement insurance, also known as Medigap, helps cover the “gaps” in Original Medicare by paying for a portion or all of the out-of-pocket costs associated with Original Medicare, like coinsurance and deductibles. As such, you may only purchase Medigap if you have Original Medicare, not Medicare Advantage.
Some Medigap policies also provide coverage when you travel outside the United States and need medical attention. Medigap is offered by private insurance companies, though the plan types are federally standardized and subject to state regulations. Different plan types have different levels of coverages and benefits.
Enrollment Periods For Medigap
- Medigap Initial Enrollment Period: Begins the month you turn 65 and have Medicare Part B coverage and lasts for 6 months
After your initial enrollment period (IEP) with Medigap, you may apply at any time throughout the year to join a Medigap plan. However, outside of your IEP, insurers are permitted to use medical underwriting and look at your health history to increase your premium, limit your plan options, or deny coverage altogether.
Special Enrollment Periods for Medicare
A Special Enrollment Period (SEP) is a period triggered by a qualifying event that allows you to enroll in coverage outside of the usual enrollment periods. Depending on the event, the SEP may last anywhere from 90 days to 8 months. Common triggers for SEPs include:
- You moved out of your plan’s service area. You may have an SEP to enroll in a new Medicare Advantage plan or return to Original Medicare that lasts for three months, beginning either the month prior to your move or the month of your move.
- You delayed enrolling in Medicare Part B because you still had employer-sponsored health insurance. You may have an SEP to enroll in Part B that lasts for 8 months, beginning the month after your other health coverage ends.
- You moved into or out of an institution such as a skilled nursing facility or long-term care hospital: You may have an SEP to enroll in Medicare Advantage or Part D, or return to Original Medicare. This SEP lasts as long as you live at the institution and for an additional two months after you leave.
How to Enroll in Medicare
You can enroll in Original Medicare, Medicare Advantage, Medicare Part D, or Medigap during their respective enrollment periods, as outlined in the previous sections. This can be done online, over the phone, or with a trusted insurance agent. No matter what type of Medicare plan you enroll in, you will likely need to provide the following:
- Your date and place of birth, usually verified through your birth certificate or Permanent Resident Card if you are not a U.S. citizen
- Your Social Security number, verified with your Social Security card
- Tax and income forms, such as W-2s
- Your Medicaid number, along with start and end dates for coverage (if applicable)
- Your current health insurance, including start and end dates for both coverage and your employment if it’s a group health plan (if applicable)